Adding upstream version 4:7.4.7.upstream/4%7.4.7upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

99 files changed, 24847 insertions, 0 deletions

diff --git a/sd/source/ui/slidesorter/cache/SlsBitmapCache.cxx b/sd/source/ui/slidesorter/cache/SlsBitmapCache.cxx
new file mode 100644
index 000000000..87c727408
--- /dev/null
+++ b/sd/source/ui/slidesorter/cache/SlsBitmapCache.cxx
@@ -0,0 +1,550 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <memory>
+#include <unordered_map>
+#include "SlsBitmapCache.hxx"
+#include "SlsCacheCompactor.hxx"
+#include "SlsBitmapCompressor.hxx"
+#include "SlsCacheConfiguration.hxx"
+
+#include <sal/log.hxx>
+
+// Define the default value for the maximal cache size that is used for
+// previews that are currently not visible.  The visible previews are all
+// held in memory at all times.  This default is used only when the
+// configuration does not have a value.
+const sal_Int32 MAXIMAL_CACHE_SIZE = 4*1024L*1024L;
+
+using namespace ::com::sun::star::uno;
+
+namespace sd::slidesorter::cache {
+
+class BitmapCache::CacheEntry
+{
+public:
+    CacheEntry(const BitmapEx& rBitmap, sal_Int32 nLastAccessTime, bool bIsPrecious);
+    CacheEntry(sal_Int32 nLastAccessTime, bool bIsPrecious);
+    inline void Recycle (const CacheEntry& rEntry);
+    inline sal_Int32 GetMemorySize() const;
+    void Compress (const std::shared_ptr<BitmapCompressor>& rpCompressor);
+    inline void Decompress();
+
+    bool IsUpToDate() const { return mbIsUpToDate; }
+    void SetUpToDate (bool bIsUpToDate) { mbIsUpToDate = bIsUpToDate; }
+    sal_Int32 GetAccessTime() const { return mnLastAccessTime; }
+    void SetAccessTime (sal_Int32 nAccessTime) { mnLastAccessTime = nAccessTime; }
+
+    const BitmapEx& GetPreview() const { return maPreview; }
+    inline void SetPreview (const BitmapEx& rPreview);
+    bool HasPreview() const;
+
+    const BitmapEx& GetMarkedPreview() const { return maMarkedPreview; }
+    inline void SetMarkedPreview (const BitmapEx& rMarkePreview);
+
+    bool HasReplacement() const { return (mpReplacement != nullptr); }
+    inline bool HasLosslessReplacement() const;
+    void Invalidate() { mpReplacement.reset(); mpCompressor.reset(); mbIsUpToDate = false; }
+    bool IsPrecious() const { return mbIsPrecious; }
+    void SetPrecious (bool bIsPrecious) { mbIsPrecious = bIsPrecious; }
+
+private:
+    BitmapEx maPreview;
+    BitmapEx maMarkedPreview;
+    std::shared_ptr<BitmapReplacement> mpReplacement;
+    std::shared_ptr<BitmapCompressor> mpCompressor;
+    bool mbIsUpToDate;
+    sal_Int32 mnLastAccessTime;
+    // When this flag is set then the bitmap is not modified by a cache
+    // compactor.
+    bool mbIsPrecious;
+};
+
+namespace {
+
+class CacheHash {
+public:
+    size_t operator()(const BitmapCache::CacheKey& p) const
+    { return reinterpret_cast<size_t>(p); }
+};
+
+}
+
+class BitmapCache::CacheBitmapContainer
+    : public std::unordered_map<CacheKey, CacheEntry, CacheHash>
+{
+public:
+    CacheBitmapContainer() {}
+};
+
+namespace {
+
+typedef ::std::vector<
+    ::std::pair< ::sd::slidesorter::cache::BitmapCache::CacheKey,
+      ::sd::slidesorter::cache::BitmapCache::CacheEntry>
+    > SortableBitmapContainer;
+
+    /** Compare elements of the bitmap cache according to their last access
+        time.
+    */
+    class AccessTimeComparator
+    {
+    public:
+        bool operator () (
+            const SortableBitmapContainer::value_type& e1,
+            const SortableBitmapContainer::value_type& e2)
+        {
+            return e1.second.GetAccessTime() < e2.second.GetAccessTime();
+        }
+    };
+
+} // end of anonymous namespace
+
+//=====  BitmapCache  =========================================================
+
+BitmapCache::BitmapCache ()
+    : mpBitmapContainer(new CacheBitmapContainer()),
+      mnNormalCacheSize(0),
+      mnPreciousCacheSize(0),
+      mnCurrentAccessTime(0),
+      mnMaximalNormalCacheSize(MAXIMAL_CACHE_SIZE),
+      mbIsFull(false)
+{
+    Any aCacheSize (CacheConfiguration::Instance()->GetValue("CacheSize"));
+    if (aCacheSize.has<sal_Int32>())
+        aCacheSize >>= mnMaximalNormalCacheSize;
+
+    mpCacheCompactor = CacheCompactor::Create(*this,mnMaximalNormalCacheSize);
+}
+
+BitmapCache::~BitmapCache()
+{
+    Clear();
+}
+
+void BitmapCache::Clear()
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    mpBitmapContainer->clear();
+    mnNormalCacheSize = 0;
+    mnPreciousCacheSize = 0;
+    mnCurrentAccessTime = 0;
+}
+
+bool BitmapCache::HasBitmap (const CacheKey& rKey)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    CacheBitmapContainer::iterator iEntry (mpBitmapContainer->find(rKey));
+    return (iEntry != mpBitmapContainer->end()
+        && (iEntry->second.HasPreview() || iEntry->second.HasReplacement()));
+}
+
+bool BitmapCache::BitmapIsUpToDate (const CacheKey& rKey)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    bool bIsUpToDate = false;
+    CacheBitmapContainer::iterator aIterator (mpBitmapContainer->find(rKey));
+    if (aIterator != mpBitmapContainer->end())
+        bIsUpToDate = aIterator->second.IsUpToDate();
+
+    return bIsUpToDate;
+}
+
+BitmapEx BitmapCache::GetBitmap (const CacheKey& rKey)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    CacheBitmapContainer::iterator iEntry (mpBitmapContainer->find(rKey));
+    if (iEntry == mpBitmapContainer->end())
+    {
+        // Create an empty bitmap for the given key that acts as placeholder
+        // until we are given the real one.  Mark it as not being up to date.
+        SetBitmap(rKey, BitmapEx(), false);
+        iEntry = mpBitmapContainer->find(rKey);
+        iEntry->second.SetUpToDate(false);
+    }
+    else
+    {
+        iEntry->second.SetAccessTime(mnCurrentAccessTime++);
+
+        // Maybe we have to decompress the preview.
+        if ( ! iEntry->second.HasPreview() && iEntry->second.HasReplacement())
+        {
+            UpdateCacheSize(iEntry->second, REMOVE);
+            iEntry->second.Decompress();
+            UpdateCacheSize(iEntry->second, ADD);
+        }
+    }
+    return iEntry->second.GetPreview();
+}
+
+BitmapEx BitmapCache::GetMarkedBitmap (const CacheKey& rKey)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    CacheBitmapContainer::iterator iEntry (mpBitmapContainer->find(rKey));
+    if (iEntry != mpBitmapContainer->end())
+    {
+        iEntry->second.SetAccessTime(mnCurrentAccessTime++);
+        return iEntry->second.GetMarkedPreview();
+    }
+    else
+        return BitmapEx();
+}
+
+void BitmapCache::ReleaseBitmap (const CacheKey& rKey)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    CacheBitmapContainer::iterator aIterator (mpBitmapContainer->find(rKey));
+    if (aIterator != mpBitmapContainer->end())
+    {
+        UpdateCacheSize(aIterator->second, REMOVE);
+        mpBitmapContainer->erase(aIterator);
+    }
+}
+
+bool BitmapCache::InvalidateBitmap (const CacheKey& rKey)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    CacheBitmapContainer::iterator iEntry (mpBitmapContainer->find(rKey));
+    if (iEntry != mpBitmapContainer->end())
+    {
+        iEntry->second.SetUpToDate(false);
+
+        // When there is a preview then we release the replacement.  The
+        // preview itself is kept until a new one is created.
+        if (iEntry->second.HasPreview())
+        {
+            UpdateCacheSize(iEntry->second, REMOVE);
+            iEntry->second.Invalidate();
+            UpdateCacheSize(iEntry->second, ADD);
+        }
+        return true;
+    }
+    else
+        return false;
+}
+
+void BitmapCache::InvalidateCache()
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    for (auto& rEntry : *mpBitmapContainer)
+    {
+        rEntry.second.Invalidate();
+    }
+    ReCalculateTotalCacheSize();
+}
+
+void BitmapCache::SetBitmap (
+    const CacheKey& rKey,
+    const BitmapEx& rPreview,
+    bool bIsPrecious)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    CacheBitmapContainer::iterator iEntry (mpBitmapContainer->find(rKey));
+    if (iEntry != mpBitmapContainer->end())
+    {
+        UpdateCacheSize(iEntry->second, REMOVE);
+        iEntry->second.SetPreview(rPreview);
+        iEntry->second.SetUpToDate(true);
+        iEntry->second.SetAccessTime(mnCurrentAccessTime++);
+    }
+    else
+    {
+        iEntry = mpBitmapContainer->emplace(
+            rKey,
+            CacheEntry(rPreview, mnCurrentAccessTime++, bIsPrecious)
+            ).first;
+    }
+
+    if (iEntry != mpBitmapContainer->end())
+        UpdateCacheSize(iEntry->second, ADD);
+}
+
+void BitmapCache::SetMarkedBitmap (
+    const CacheKey& rKey,
+    const BitmapEx& rPreview)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    CacheBitmapContainer::iterator iEntry (mpBitmapContainer->find(rKey));
+    if (iEntry != mpBitmapContainer->end())
+    {
+        UpdateCacheSize(iEntry->second, REMOVE);
+        iEntry->second.SetMarkedPreview(rPreview);
+        iEntry->second.SetAccessTime(mnCurrentAccessTime++);
+        UpdateCacheSize(iEntry->second, ADD);
+    }
+}
+
+void BitmapCache::SetPrecious (const CacheKey& rKey, bool bIsPrecious)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    CacheBitmapContainer::iterator iEntry (mpBitmapContainer->find(rKey));
+    if (iEntry != mpBitmapContainer->end())
+    {
+        if (iEntry->second.IsPrecious() != bIsPrecious)
+        {
+            UpdateCacheSize(iEntry->second, REMOVE);
+            iEntry->second.SetPrecious(bIsPrecious);
+            UpdateCacheSize(iEntry->second, ADD);
+        }
+    }
+    else if (bIsPrecious)
+    {
+        iEntry = mpBitmapContainer->emplace(
+            rKey,
+            CacheEntry(BitmapEx(), mnCurrentAccessTime++, bIsPrecious)
+            ).first;
+        UpdateCacheSize(iEntry->second, ADD);
+    }
+}
+
+void BitmapCache::ReCalculateTotalCacheSize()
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    mnNormalCacheSize = 0;
+    mnPreciousCacheSize = 0;
+    for (const auto& rEntry : *mpBitmapContainer)
+    {
+        if (rEntry.second.IsPrecious())
+            mnPreciousCacheSize += rEntry.second.GetMemorySize();
+        else
+            mnNormalCacheSize += rEntry.second.GetMemorySize();
+    }
+    mbIsFull = (mnNormalCacheSize  >= mnMaximalNormalCacheSize);
+
+    SAL_INFO("sd.sls", __func__ << ": cache size is " << mnNormalCacheSize << "/" << mnPreciousCacheSize);
+}
+
+void BitmapCache::Recycle (const BitmapCache& rCache)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    for (const auto& rOtherEntry : *rCache.mpBitmapContainer)
+    {
+        CacheBitmapContainer::iterator iEntry (mpBitmapContainer->find(rOtherEntry.first));
+        if (iEntry == mpBitmapContainer->end())
+        {
+            iEntry = mpBitmapContainer->emplace(
+                rOtherEntry.first,
+                CacheEntry(mnCurrentAccessTime++, true)
+                ).first;
+            UpdateCacheSize(iEntry->second, ADD);
+        }
+        if (iEntry != mpBitmapContainer->end())
+        {
+            UpdateCacheSize(iEntry->second, REMOVE);
+            iEntry->second.Recycle(rOtherEntry.second);
+            UpdateCacheSize(iEntry->second, ADD);
+        }
+    }
+}
+
+BitmapCache::CacheIndex BitmapCache::GetCacheIndex() const
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    // Create a copy of the bitmap container.
+    SortableBitmapContainer aSortedContainer;
+    aSortedContainer.reserve(mpBitmapContainer->size());
+
+    // Copy the relevant entries.
+    for (const auto& rEntry : *mpBitmapContainer)
+    {
+        if ( rEntry.second.IsPrecious())
+            continue;
+
+        if ( ! rEntry.second.HasPreview())
+            continue;
+
+        aSortedContainer.emplace_back(rEntry.first, rEntry.second);
+    }
+
+    // Sort the remaining entries.
+    ::std::sort(aSortedContainer.begin(), aSortedContainer.end(), AccessTimeComparator());
+
+    // Return a list with the keys of the sorted entries.
+    CacheIndex aIndex;
+    aIndex.reserve(aSortedContainer.size());
+    for (const auto& rIndexEntry : aSortedContainer)
+        aIndex.push_back(rIndexEntry.first);
+    return aIndex;
+}
+
+void BitmapCache::Compress (
+    const CacheKey& rKey,
+    const std::shared_ptr<BitmapCompressor>& rpCompressor)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    CacheBitmapContainer::iterator iEntry (mpBitmapContainer->find(rKey));
+    if (iEntry != mpBitmapContainer->end() && iEntry->second.HasPreview())
+    {
+        UpdateCacheSize(iEntry->second, REMOVE);
+        iEntry->second.Compress(rpCompressor);
+        UpdateCacheSize(iEntry->second, ADD);
+    }
+}
+
+void BitmapCache::UpdateCacheSize (const CacheEntry& rEntry, CacheOperation eOperation)
+{
+    sal_Int32 nEntrySize (rEntry.GetMemorySize());
+    sal_Int32& rCacheSize (rEntry.IsPrecious() ? mnPreciousCacheSize : mnNormalCacheSize);
+    switch (eOperation)
+    {
+        case ADD:
+            rCacheSize += nEntrySize;
+            if ( ! rEntry.IsPrecious() && mnNormalCacheSize>mnMaximalNormalCacheSize)
+            {
+                mbIsFull = true;
+                SAL_INFO("sd.sls", __func__ << ": cache size is " << mnNormalCacheSize << " > " << mnMaximalNormalCacheSize);
+                mpCacheCompactor->RequestCompaction();
+            }
+            break;
+
+        case REMOVE:
+            rCacheSize -= nEntrySize;
+            if (mnNormalCacheSize < mnMaximalNormalCacheSize)
+                mbIsFull = false;
+            break;
+
+        default:
+            assert(false);
+            break;
+    }
+}
+
+//===== CacheEntry ============================================================
+
+BitmapCache::CacheEntry::CacheEntry(
+    sal_Int32 nLastAccessTime,
+    bool bIsPrecious)
+    : mbIsUpToDate(true),
+      mnLastAccessTime(nLastAccessTime),
+      mbIsPrecious(bIsPrecious)
+{
+}
+
+BitmapCache::CacheEntry::CacheEntry(
+    const BitmapEx& rPreview,
+    sal_Int32 nLastAccessTime,
+    bool bIsPrecious)
+    : maPreview(rPreview),
+      mbIsUpToDate(true),
+      mnLastAccessTime(nLastAccessTime),
+      mbIsPrecious(bIsPrecious)
+{
+}
+
+inline void BitmapCache::CacheEntry::Recycle (const CacheEntry& rEntry)
+{
+    if ((rEntry.HasPreview() || rEntry.HasLosslessReplacement())
+        && ! (HasPreview() || HasLosslessReplacement()))
+    {
+        maPreview = rEntry.maPreview;
+        maMarkedPreview = rEntry.maMarkedPreview;
+        mpReplacement = rEntry.mpReplacement;
+        mpCompressor = rEntry.mpCompressor;
+        mnLastAccessTime = rEntry.mnLastAccessTime;
+        mbIsUpToDate = rEntry.mbIsUpToDate;
+    }
+}
+
+inline sal_Int32 BitmapCache::CacheEntry::GetMemorySize() const
+{
+    sal_Int32 nSize (0);
+    nSize += maPreview.GetSizeBytes();
+    nSize += maMarkedPreview.GetSizeBytes();
+    if (mpReplacement != nullptr)
+        nSize += mpReplacement->GetMemorySize();
+    return nSize;
+}
+
+void BitmapCache::CacheEntry::Compress (const std::shared_ptr<BitmapCompressor>& rpCompressor)
+{
+    if (  maPreview.IsEmpty())
+        return;
+
+    if (mpReplacement == nullptr)
+    {
+        mpReplacement = rpCompressor->Compress(maPreview);
+
+#ifdef DEBUG_SD_SLSBITMAPCACHE
+        sal_uInt32 nOldSize (maPreview.GetSizeBytes());
+        sal_uInt32 nNewSize (mpReplacement.get()!=NULL ? mpReplacement->GetMemorySize() : 0);
+        if (nOldSize == 0)
+            nOldSize = 1;
+        sal_Int32 nRatio (100L * nNewSize / nOldSize);
+        SAL_INFO("sd.sls", __func__ << ": compressing bitmap for " << %x << " from " << nOldSize << " to " << nNewSize << " bytes (" << nRatio << "%)");
+#endif
+
+        mpCompressor = rpCompressor;
+    }
+
+    maPreview.SetEmpty();
+    maMarkedPreview.SetEmpty();
+}
+
+inline void BitmapCache::CacheEntry::Decompress()
+{
+    if (mpReplacement != nullptr && mpCompressor != nullptr && maPreview.IsEmpty())
+    {
+        maPreview = mpCompressor->Decompress(*mpReplacement);
+        maMarkedPreview.SetEmpty();
+        if ( ! mpCompressor->IsLossless())
+            mbIsUpToDate = false;
+    }
+}
+
+inline void BitmapCache::CacheEntry::SetPreview (const BitmapEx& rPreview)
+{
+    maPreview = rPreview;
+    maMarkedPreview.SetEmpty();
+    mpReplacement.reset();
+    mpCompressor.reset();
+}
+
+bool BitmapCache::CacheEntry::HasPreview() const
+{
+    return ! maPreview.IsEmpty();
+}
+
+inline void BitmapCache::CacheEntry::SetMarkedPreview (const BitmapEx& rMarkedPreview)
+{
+    maMarkedPreview = rMarkedPreview;
+}
+
+inline bool BitmapCache::CacheEntry::HasLosslessReplacement() const
+{
+    return mpReplacement != nullptr && mpCompressor != nullptr && mpCompressor->IsLossless();
+}
+
+} // end of namespace ::sd::slidesorter::cache
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/cache/SlsBitmapCache.hxx b/sd/source/ui/slidesorter/cache/SlsBitmapCache.hxx
new file mode 100644
index 000000000..98b0bcb53
--- /dev/null
+++ b/sd/source/ui/slidesorter/cache/SlsBitmapCache.hxx
@@ -0,0 +1,208 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <vcl/bitmapex.hxx>
+#include <osl/mutex.hxx>
+#include <memory>
+
+class SdrPage;
+
+namespace sd::slidesorter::cache
+{
+class CacheCompactor;
+class BitmapCompressor;
+
+/** This low level cache is the actual bitmap container.  It supports a
+    precious flag for every preview bitmap and keeps track of total sizes
+    for all previews with/without this flag.  The precious flag is used by
+    compaction algorithms to determine which previews may be compressed or
+    even discarded and which have to remain in their original form.  The
+    precious flag is usually set for the visible previews.
+
+    Additionally to the actual preview there is an optional marked preview.
+    This is used for slides excluded from the slide show which have a preview
+    that shows a mark (some sort of bitmap overlay) to that effect.
+*/
+class BitmapCache
+{
+public:
+    /** The key for looking up preview bitmaps is a pointer to an SdrPage
+        object.  The prior use of PageObjectViewObjectContact objects (which
+        ultimately use them) turned out to be less suitable because their
+        life time is shorter then that of the page objects.  Frequent
+        destruction and re-creation of the preview bitmaps was the result.
+    */
+    typedef const SdrPage* CacheKey;
+    class CacheEntry;
+    class CacheBitmapContainer;
+    typedef ::std::vector<CacheKey> CacheIndex;
+
+    /** Create a new cache for bitmap objects.
+        The default value from the configuration is used.
+        When that does not exist then an internal default value is
+        used.
+    */
+    explicit BitmapCache();
+
+    /** The destructor clears the cache and releases all bitmaps still in it.
+    */
+    ~BitmapCache();
+
+    /** Remove all preview bitmaps from the cache.  After this call the
+        cache is empty.
+    */
+    void Clear();
+
+    /** Return <TRUE/> when the cache is full, i.e. the cache compactor had
+        to be run.
+    */
+    bool IsFull() const { return mbIsFull; }
+
+    /** Return the memory size that is occupied by all non-precious bitmaps
+        in the cache.
+    */
+    sal_Int32 GetSize() const { return mnNormalCacheSize; }
+
+    /** Return <TRUE/> when a preview bitmap exists for the given key.
+    */
+    bool HasBitmap(const CacheKey& rKey);
+
+    /** Return <TRUE/> when a preview bitmap exists for the given key and
+        when it is up-to-date.
+    */
+    bool BitmapIsUpToDate(const CacheKey& rKey);
+
+    /** Return the preview bitmap for the given contact object.
+    */
+    BitmapEx GetBitmap(const CacheKey& rKey);
+
+    /** Return the marked preview bitmap for the given contact object.
+    */
+    BitmapEx GetMarkedBitmap(const CacheKey& rKey);
+
+    /** Release the reference to the preview bitmap that is associated with
+        the given key.
+    */
+    void ReleaseBitmap(const CacheKey& rKey);
+
+    /** Mark the specified preview bitmap as not being up-to-date
+        anymore.
+        @return
+            When the key references a page in the cache then
+            return <TRUE/>.  When the key is not known then <FALSE/>
+            is returned.
+    */
+    bool InvalidateBitmap(const CacheKey& rKey);
+
+    /** Mark all preview bitmaps as not being up-to-date anymore.
+    */
+    void InvalidateCache();
+
+    /** Add or replace a bitmap for the given key.
+    */
+    void SetBitmap(const CacheKey& rKey, const BitmapEx& rPreview, bool bIsPrecious);
+
+    /** Add or replace a marked bitmap for the given key.
+    */
+    void SetMarkedBitmap(const CacheKey& rKey, const BitmapEx& rPreview);
+
+    /** Mark the specified preview bitmap as precious, i.e. that it must not
+        be compressed or otherwise removed from the cache.
+    */
+    void SetPrecious(const CacheKey& rKey, bool bIsPrecious);
+
+    /** Calculate the cache size.  This should rarely be necessary because
+        the cache size is tracked with each modification of preview
+        bitmaps.
+    */
+    void ReCalculateTotalCacheSize();
+
+    /** Use the previews in the given cache to initialize missing previews.
+    */
+    void Recycle(const BitmapCache& rCache);
+
+    /** Return a list of sorted cache keys that represent an index into (a
+        part of) the cache.  The entries of the index are sorted according
+        to last access times with the least recently access time first.
+        Entries with the precious flag set are omitted.
+        Entries with that have no preview bitmaps are omitted.
+    */
+    CacheIndex GetCacheIndex() const;
+
+    /** Compress the specified preview bitmap with the given bitmap
+        compressor.  A reference to the compressor is stored for later
+        decompression.
+    */
+    void Compress(const CacheKey& rKey, const std::shared_ptr<BitmapCompressor>& rpCompressor);
+
+private:
+    mutable ::osl::Mutex maMutex;
+
+    std::unique_ptr<CacheBitmapContainer> mpBitmapContainer;
+
+    /** Total size of bytes that are occupied by bitmaps in the cache for
+        whom the slides are currently not inside the visible area.
+    */
+    sal_Int32 mnNormalCacheSize;
+
+    /** Total size of bytes that are occupied by bitmaps in the cache for
+        whom the slides are currently visible.
+    */
+    sal_Int32 mnPreciousCacheSize;
+
+    /** At the moment the access time is not an actual time or date value
+        but a counter that is increased with every access.  It thus defines
+        the same ordering as a true time.
+    */
+    sal_Int32 mnCurrentAccessTime;
+
+    /** The maximal cache size for the off-screen preview bitmaps.  When
+        mnNormalCacheSize grows larger than this value then the
+        mpCacheCompactor member is used to reduce the cache size.
+    */
+    sal_Int32 mnMaximalNormalCacheSize;
+
+    /** The cache compactor is used to reduce the number of bytes used by
+        off-screen preview bitmaps.
+    */
+    ::std::unique_ptr<CacheCompactor> mpCacheCompactor;
+
+    /** This flag stores if the cache is or recently was full, i.e. the
+        cache compactor has or had to be run in order to reduce the cache
+        size to the allowed value.
+    */
+    bool mbIsFull;
+
+    /** Update mnNormalCacheSize or mnPreciousCacheSize according to the
+        precious flag of the specified preview bitmap and the specified
+        operation.
+    */
+    enum CacheOperation
+    {
+        ADD,
+        REMOVE
+    };
+    void UpdateCacheSize(const CacheEntry& rKey, CacheOperation eOperation);
+};
+
+} // end of namespace ::sd::slidesorter::cache
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/cache/SlsBitmapCompressor.cxx b/sd/source/ui/slidesorter/cache/SlsBitmapCompressor.cxx
new file mode 100644
index 000000000..d4da935dd
--- /dev/null
+++ b/sd/source/ui/slidesorter/cache/SlsBitmapCompressor.cxx
@@ -0,0 +1,197 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "SlsBitmapCompressor.hxx"
+
+#include <tools/stream.hxx>
+#include <vcl/bitmapex.hxx>
+#include <vcl/filter/PngImageReader.hxx>
+#include <vcl/pngwrite.hxx>
+
+namespace sd::slidesorter::cache {
+
+//===== NoBitmapCompression ===================================================
+
+/** This dummy replacement simply stores a shared pointer to the original
+    preview bitmap.
+*/
+class NoBitmapCompression::DummyReplacement
+    : public BitmapReplacement
+{
+public:
+    BitmapEx maPreview;
+
+    explicit DummyReplacement (const BitmapEx& rPreview) : maPreview(rPreview)  { }
+    virtual ~DummyReplacement() {}
+    virtual sal_Int32 GetMemorySize() const override { return maPreview.GetSizeBytes(); }
+};
+
+std::shared_ptr<BitmapReplacement> NoBitmapCompression::Compress (const BitmapEx& rBitmap) const
+{
+    return std::make_shared<DummyReplacement>(rBitmap);
+}
+
+BitmapEx NoBitmapCompression::Decompress (const BitmapReplacement& rBitmapData) const
+{
+    return dynamic_cast<const DummyReplacement&>(rBitmapData).maPreview;
+}
+
+bool NoBitmapCompression::IsLossless() const
+{
+    return true;
+}
+
+//===== CompressionByDeletion =================================================
+
+std::shared_ptr<BitmapReplacement> CompressionByDeletion::Compress (const BitmapEx& ) const
+{
+    return std::shared_ptr<BitmapReplacement>();
+}
+
+BitmapEx CompressionByDeletion::Decompress (const BitmapReplacement& ) const
+{
+    // Return a NULL pointer.  This will eventually lead to a request for
+    // the creation of a new one.
+    return BitmapEx();
+}
+
+bool CompressionByDeletion::IsLossless() const
+{
+    return false;
+}
+
+//===== ResolutionReduction ===================================================
+
+/** Store a scaled down bitmap together with the original size.
+*/
+class ResolutionReduction::ResolutionReducedReplacement : public BitmapReplacement
+{
+public:
+    BitmapEx maPreview;
+    Size maOriginalSize;
+
+    virtual ~ResolutionReducedReplacement();
+    virtual sal_Int32 GetMemorySize() const override;
+};
+
+ResolutionReduction::ResolutionReducedReplacement::~ResolutionReducedReplacement()
+{
+}
+
+sal_Int32 ResolutionReduction::ResolutionReducedReplacement::GetMemorySize() const
+{
+    return maPreview.GetSizeBytes();
+}
+
+std::shared_ptr<BitmapReplacement> ResolutionReduction::Compress (
+    const BitmapEx& rBitmap) const
+{
+    auto pResult = std::make_shared<ResolutionReducedReplacement>();
+    pResult->maPreview = rBitmap;
+    Size aSize (rBitmap.GetSizePixel());
+    pResult->maOriginalSize = aSize;
+    if (aSize.Width()>0 && aSize.Width()<mnWidth)
+    {
+        int nHeight = aSize.Height() * mnWidth / aSize.Width() ;
+        pResult->maPreview.Scale(Size(mnWidth,nHeight));
+    }
+
+    return pResult;
+}
+
+BitmapEx ResolutionReduction::Decompress (const BitmapReplacement& rBitmapData) const
+{
+    BitmapEx aResult;
+
+    const ResolutionReducedReplacement* pData (
+        dynamic_cast<const ResolutionReducedReplacement*>(&rBitmapData));
+
+    if ( pData && ! pData->maPreview.IsEmpty())
+    {
+        aResult = pData->maPreview;
+        if (pData->maOriginalSize.Width() > mnWidth)
+            aResult.Scale(pData->maOriginalSize);
+    }
+
+    return aResult;
+}
+
+bool ResolutionReduction::IsLossless() const
+{
+    return false;
+}
+
+//===== PNGCompression ========================================================
+
+class PngCompression::PngReplacement : public BitmapReplacement
+{
+public:
+    void* mpData;
+    sal_Int32 mnDataSize;
+    PngReplacement()
+        : mpData(nullptr),
+          mnDataSize(0)
+    {}
+    virtual ~PngReplacement()
+    {
+        delete [] static_cast<char*>(mpData);
+    }
+    virtual sal_Int32 GetMemorySize() const override
+    {
+        return mnDataSize;
+    }
+};
+
+std::shared_ptr<BitmapReplacement> PngCompression::Compress (const BitmapEx& rBitmap) const
+{
+    vcl::PNGWriter aWriter(rBitmap);
+    SvMemoryStream aStream (32768, 32768);
+    aWriter.Write(aStream);
+
+    auto pResult = std::make_shared<PngReplacement>();
+    pResult->mnDataSize = aStream.Tell();
+    pResult->mpData = new char[pResult->mnDataSize];
+    memcpy(pResult->mpData, aStream.GetData(), pResult->mnDataSize);
+
+    return pResult;
+}
+
+BitmapEx PngCompression::Decompress (
+    const BitmapReplacement& rBitmapData) const
+{
+    BitmapEx aResult;
+    const PngReplacement* pData (dynamic_cast<const PngReplacement*>(&rBitmapData));
+    if (pData != nullptr)
+    {
+        SvMemoryStream aStream (pData->mpData, pData->mnDataSize, StreamMode::READ);
+        vcl::PngImageReader aReader (aStream);
+        aResult = aReader.read().GetBitmap();
+    }
+
+    return aResult;
+}
+
+bool PngCompression::IsLossless() const
+{
+    return true;
+}
+
+} // end of namespace ::sd::slidesorter::cache
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/cache/SlsBitmapCompressor.hxx b/sd/source/ui/slidesorter/cache/SlsBitmapCompressor.hxx
new file mode 100644
index 000000000..4754bead9
--- /dev/null
+++ b/sd/source/ui/slidesorter/cache/SlsBitmapCompressor.hxx
@@ -0,0 +1,138 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <sal/types.h>
+#include <memory>
+
+class BitmapEx;
+
+namespace sd::slidesorter::cache
+{
+class BitmapReplacement;
+
+/** This interface class provides the minimal method set for classes that
+    implement the compression and decompression of preview bitmaps.
+*/
+class BitmapCompressor
+{
+public:
+    /** Compress the given bitmap into a replacement format that is specific
+        to the compressor class.
+    */
+    virtual std::shared_ptr<BitmapReplacement> Compress(const BitmapEx& rBitmap) const = 0;
+
+    /** Decompress the given replacement data into a preview bitmap.
+        Depending on the compression technique the returned bitmap may
+        differ from the original bitmap given to the Compress() method.  It
+        may even of the wrong size or empty or the NULL pointer.  It is the
+        task of the caller to create a new preview bitmap if the returned
+        one is not as desired.
+    */
+    virtual BitmapEx Decompress(const BitmapReplacement& rBitmapData) const = 0;
+
+    /** Return whether the compression and decompression is lossless.  This
+        value is used by the caller of Decompress() to decide whether to use
+        the returned bitmap as is or if a new preview has to be created.
+    */
+    virtual bool IsLossless() const = 0;
+
+protected:
+    ~BitmapCompressor() {}
+};
+
+/** Interface for preview bitmap replacements.  Each bitmap
+    compressor/decompressor has to provide an implementation that is
+    suitable to store the compressed bitmaps.
+*/
+class BitmapReplacement
+{
+public:
+    virtual sal_Int32 GetMemorySize() const { return 0; }
+
+protected:
+    ~BitmapReplacement() {}
+};
+
+/** This is one trivial bitmap compressor.  It stores bitmaps unmodified
+    instead of compressing them.
+    This compressor is lossless.
+*/
+class NoBitmapCompression : public BitmapCompressor
+{
+    class DummyReplacement;
+
+public:
+    virtual ~NoBitmapCompression() {}
+    virtual std::shared_ptr<BitmapReplacement> Compress(const BitmapEx& rpBitmap) const override;
+    virtual BitmapEx Decompress(const BitmapReplacement& rBitmapData) const override;
+    virtual bool IsLossless() const override;
+};
+
+/** This is another trivial bitmap compressor.  Instead of compressing a
+    bitmap, it throws the bitmap away.  Its Decompress() method returns a
+    NULL pointer.  The caller has to create a new preview bitmap instead.
+    This compressor clearly is not lossless.
+*/
+class CompressionByDeletion : public BitmapCompressor
+{
+public:
+    virtual ~CompressionByDeletion() {}
+    virtual std::shared_ptr<BitmapReplacement> Compress(const BitmapEx& rBitmap) const override;
+    virtual BitmapEx Decompress(const BitmapReplacement& rBitmapData) const override;
+    virtual bool IsLossless() const override;
+};
+
+/** Compress a preview bitmap by reducing its resolution.  While the aspect
+    ratio is maintained the horizontal resolution is scaled down to 100
+    pixels.
+    This compressor is not lossless.
+*/
+class ResolutionReduction : public BitmapCompressor
+{
+    class ResolutionReducedReplacement;
+    static const sal_Int32 mnWidth = 100;
+
+public:
+    virtual ~ResolutionReduction() {}
+    virtual std::shared_ptr<BitmapReplacement> Compress(const BitmapEx& rpBitmap) const override;
+    /** Scale the replacement bitmap up to the original size.
+    */
+    virtual BitmapEx Decompress(const BitmapReplacement& rBitmapData) const override;
+    virtual bool IsLossless() const override;
+};
+
+/** Compress preview bitmaps using the PNG format.
+    This compressor is lossless.
+*/
+class PngCompression : public BitmapCompressor
+{
+    class PngReplacement;
+
+public:
+    virtual ~PngCompression() {}
+    virtual std::shared_ptr<BitmapReplacement> Compress(const BitmapEx& rBitmap) const override;
+    virtual BitmapEx Decompress(const BitmapReplacement& rBitmapData) const override;
+    virtual bool IsLossless() const override;
+};
+
+} // end of namespace ::sd::slidesorter::cache
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/cache/SlsBitmapFactory.cxx b/sd/source/ui/slidesorter/cache/SlsBitmapFactory.cxx
new file mode 100644
index 000000000..a9182c2a2
--- /dev/null
+++ b/sd/source/ui/slidesorter/cache/SlsBitmapFactory.cxx
@@ -0,0 +1,71 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "SlsBitmapFactory.hxx"
+
+#include <PreviewRenderer.hxx>
+#include <sdpage.hxx>
+#include <vcl/bitmapex.hxx>
+
+namespace sd::slidesorter::view {
+class SlideSorterView;
+class PageObjectViewObjectContact;
+}
+
+namespace sd::slidesorter::cache {
+
+BitmapFactory::BitmapFactory()
+    : maRenderer(false)
+{
+}
+
+BitmapFactory::~BitmapFactory()
+{
+}
+
+BitmapEx BitmapFactory::CreateBitmap (
+    const SdPage& rPage,
+    const Size& rPixelSize,
+    const bool bDoSuperSampling)
+{
+    Size aSize (rPixelSize);
+    if (bDoSuperSampling)
+    {
+        // Supersampling factor
+        int aSuperSamplingFactor = 2;
+        aSize.setWidth( aSize.Width() * aSuperSamplingFactor );
+        aSize.setHeight( aSize.Height() * aSuperSamplingFactor );
+    }
+
+    BitmapEx aPreview (maRenderer.RenderPage (
+        &rPage,
+        aSize,
+        true,
+        false).GetBitmapEx());
+    if (bDoSuperSampling)
+    {
+        aPreview.Scale(rPixelSize, BmpScaleFlag::BestQuality);
+    }
+
+    return aPreview;
+}
+
+} // end of namespace ::sd::slidesorter::cache
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/cache/SlsBitmapFactory.hxx b/sd/source/ui/slidesorter/cache/SlsBitmapFactory.hxx
new file mode 100644
index 000000000..c1733b825
--- /dev/null
+++ b/sd/source/ui/slidesorter/cache/SlsBitmapFactory.hxx
@@ -0,0 +1,46 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <PreviewRenderer.hxx>
+
+class SdPage;
+class Size;
+
+namespace sd::slidesorter::cache
+{
+/** This factory class creates preview bitmaps for page objects.  It is
+    merely an adapter for the PreviewRenderer.
+*/
+class BitmapFactory
+{
+public:
+    BitmapFactory();
+    ~BitmapFactory();
+
+    BitmapEx CreateBitmap(const SdPage& rPage, const Size& rPixelSize, const bool bDoSuperSampling);
+
+private:
+    PreviewRenderer maRenderer;
+};
+
+} // end of namespace ::sd::slidesorter::cache
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/cache/SlsCacheCompactor.cxx b/sd/source/ui/slidesorter/cache/SlsCacheCompactor.cxx
new file mode 100644
index 000000000..79ab9fab2
--- /dev/null
+++ b/sd/source/ui/slidesorter/cache/SlsCacheCompactor.cxx
@@ -0,0 +1,189 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <memory>
+#include "SlsCacheCompactor.hxx"
+
+#include "SlsBitmapCompressor.hxx"
+#include "SlsBitmapCache.hxx"
+#include "SlsCacheConfiguration.hxx"
+
+#include <rtl/ustring.hxx>
+#include <sal/log.hxx>
+#include <com/sun/star/uno/Any.hxx>
+
+using namespace ::com::sun::star::uno;
+
+namespace {
+
+/** This is a trivial implementation of the CacheCompactor interface class.
+    It ignores calls to RequestCompaction() and thus will never decrease the
+    total size of off-screen preview bitmaps.
+*/
+class NoCacheCompaction
+    : public ::sd::slidesorter::cache::CacheCompactor
+{
+public:
+    NoCacheCompaction (
+        ::sd::slidesorter::cache::BitmapCache& rCache,
+        sal_Int32 nMaximalCacheSize)
+        : CacheCompactor(rCache, nMaximalCacheSize)
+    {}
+
+    virtual void RequestCompaction() override { /* Ignored */ };
+
+protected:
+    virtual void Run() override { /* Do nothing */ };
+};
+
+/** This implementation of the CacheCompactor interface class uses one of
+    several bitmap compression algorithms to reduce the number of the bytes
+    of the off-screen previews in the bitmap cache.  See the documentation
+    of CacheCompactor::Create() for more details on configuration properties
+    that control the choice of compression algorithm.
+*/
+class CacheCompactionByCompression
+    : public ::sd::slidesorter::cache::CacheCompactor
+{
+public:
+    CacheCompactionByCompression (
+        ::sd::slidesorter::cache::BitmapCache& rCache,
+        sal_Int32 nMaximalCacheSize,
+        const std::shared_ptr< ::sd::slidesorter::cache::BitmapCompressor>& rpCompressor);
+
+protected:
+    virtual void Run() override;
+
+private:
+    std::shared_ptr< ::sd::slidesorter::cache::BitmapCompressor>  mpCompressor;
+};
+
+} // end of anonymous namespace
+
+namespace sd::slidesorter::cache {
+
+::std::unique_ptr<CacheCompactor> CacheCompactor::Create (
+    BitmapCache& rCache,
+    sal_Int32 nMaximalCacheSize)
+{
+    static const char sNone[] = "None";
+
+    std::shared_ptr<BitmapCompressor> pCompressor;
+    OUString sCompressionPolicy("PNGCompression");
+    Any aCompressionPolicy (CacheConfiguration::Instance()->GetValue("CompressionPolicy"));
+    if (aCompressionPolicy.has<OUString>())
+        aCompressionPolicy >>= sCompressionPolicy;
+    if (sCompressionPolicy == sNone)
+        pCompressor = std::make_shared<NoBitmapCompression>();
+    else if (sCompressionPolicy == "Erase")
+        pCompressor = std::make_shared<CompressionByDeletion>();
+    else if (sCompressionPolicy == "ResolutionReduction")
+        pCompressor = std::make_shared<ResolutionReduction>();
+    else
+        pCompressor = std::make_shared<PngCompression>();
+
+    ::std::unique_ptr<CacheCompactor> pCompactor;
+    OUString sCompactionPolicy("Compress");
+    Any aCompactionPolicy (CacheConfiguration::Instance()->GetValue("CompactionPolicy"));
+    if (aCompactionPolicy.has<OUString>())
+        aCompactionPolicy >>= sCompactionPolicy;
+    if (sCompactionPolicy == sNone)
+        pCompactor.reset(new NoCacheCompaction(rCache,nMaximalCacheSize));
+    else
+        pCompactor.reset(new CacheCompactionByCompression(rCache,nMaximalCacheSize,pCompressor));
+
+    return pCompactor;
+}
+
+void CacheCompactor::RequestCompaction()
+{
+    if ( ! mbIsCompactionRunning && ! maCompactionTimer.IsActive())
+        maCompactionTimer.Start();
+}
+
+CacheCompactor::CacheCompactor(
+    BitmapCache& rCache,
+    sal_Int32 nMaximalCacheSize)
+    : mrCache(rCache),
+      mnMaximalCacheSize(nMaximalCacheSize),
+      maCompactionTimer("sd CacheCompactor maCompactionTimer"),
+      mbIsCompactionRunning(false)
+{
+    maCompactionTimer.SetTimeout(100);
+    maCompactionTimer.SetInvokeHandler(LINK(this,CacheCompactor,CompactionCallback));
+}
+
+IMPL_LINK_NOARG(CacheCompactor, CompactionCallback, Timer *, void)
+{
+    mbIsCompactionRunning = true;
+
+    try
+    {
+        Run();
+    }
+    catch (const css::uno::RuntimeException&)
+    {
+    }
+    catch (const css::uno::Exception&)
+    {
+    }
+
+    mbIsCompactionRunning = false;
+}
+
+} // end of namespace ::sd::slidesorter::cache
+
+namespace {
+
+//===== CacheCompactionByCompression ==========================================
+
+CacheCompactionByCompression::CacheCompactionByCompression (
+    ::sd::slidesorter::cache::BitmapCache& rCache,
+    sal_Int32 nMaximalCacheSize,
+    const std::shared_ptr< ::sd::slidesorter::cache::BitmapCompressor>& rpCompressor)
+    : CacheCompactor(rCache,nMaximalCacheSize),
+      mpCompressor(rpCompressor)
+{
+}
+
+void CacheCompactionByCompression::Run()
+{
+    if (mrCache.GetSize() <= mnMaximalCacheSize)
+        return;
+
+    SAL_INFO("sd.sls", __func__ << ": bitmap cache uses too much space: " << mrCache.GetSize() << " > " << mnMaximalCacheSize);
+
+    ::sd::slidesorter::cache::BitmapCache::CacheIndex aIndex (
+        mrCache.GetCacheIndex());
+    for (const auto& rpIndex : aIndex)
+    {
+        if (rpIndex == nullptr)
+            continue;
+
+        mrCache.Compress(rpIndex, mpCompressor);
+        if (mrCache.GetSize() < mnMaximalCacheSize)
+            break;
+    }
+    mrCache.ReCalculateTotalCacheSize();
+    SAL_INFO("sd.sls", __func__ << ":    there are now " << mrCache.GetSize() << " bytes occupied");
+}
+
+} // end of anonymous namespace
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/cache/SlsCacheCompactor.hxx b/sd/source/ui/slidesorter/cache/SlsCacheCompactor.hxx
new file mode 100644
index 000000000..d694ae1a1
--- /dev/null
+++ b/sd/source/ui/slidesorter/cache/SlsCacheCompactor.hxx
@@ -0,0 +1,87 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <sal/types.h>
+#include <vcl/timer.hxx>
+#include <memory>
+
+namespace sd::slidesorter::cache {
+
+class BitmapCache;
+
+/** This is an interface class whose implementations are created via the
+    Create() factory method.
+*/
+class CacheCompactor
+{
+public:
+    virtual ~CacheCompactor() {};
+
+    /** Create a new instance of the CacheCompactor interface class.  The
+        type of compaction algorithm used depends on values from the
+        configuration: the SlideSorter/PreviewCache/CompactionPolicy
+        property of the Impress.xcs file currently supports the values
+        "None" and "Compress".  With the later the CompressionPolicy
+        property is evaluated which implementation of the BitmapCompress
+        interface class to use as bitmap compressor.
+        @param rCache
+            The bitmap cache on which to operate.
+        @param nMaximalCacheSize
+            The total number of bytes the off-screen bitmaps in the cache
+            may have.  When the Run() method is (indirectly) called the
+            compactor tries to reduce that summed size of off-screen bitmaps
+            under this number.  However, it is not guaranteed that this
+            works in all cases.
+    */
+    static ::std::unique_ptr<CacheCompactor> Create (
+        BitmapCache& rCache,
+        sal_Int32 nMaximalCacheSize);
+
+    /** Request a compaction of the off-screen previews in the bitmap
+        cache.  This calls via a timer the Run() method.
+    */
+    virtual void RequestCompaction();
+
+protected:
+    BitmapCache& mrCache;
+    sal_Int32 mnMaximalCacheSize;
+
+    CacheCompactor(
+        BitmapCache& rCache,
+        sal_Int32 nMaximalCacheSize);
+
+    /** This method actually tries to reduce the total number of bytes used
+        by the off-screen preview bitmaps.
+    */
+    virtual void Run() = 0;
+
+private:
+    /** This timer is used to collect calls to RequestCompaction() and
+        eventually call Run().
+    */
+    Timer maCompactionTimer;
+    bool mbIsCompactionRunning;
+    DECL_LINK(CompactionCallback, Timer *, void);
+};
+
+} // end of namespace ::sd::slidesorter::cache
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/cache/SlsCacheConfiguration.cxx b/sd/source/ui/slidesorter/cache/SlsCacheConfiguration.cxx
new file mode 100644
index 000000000..fd08c7627
--- /dev/null
+++ b/sd/source/ui/slidesorter/cache/SlsCacheConfiguration.cxx
@@ -0,0 +1,144 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "SlsCacheConfiguration.hxx"
+#include <vcl/svapp.hxx>
+
+#include <comphelper/processfactory.hxx>
+#include <comphelper/propertysequence.hxx>
+#include <com/sun/star/lang/XMultiServiceFactory.hpp>
+#include <com/sun/star/container/XHierarchicalNameAccess.hpp>
+#include <com/sun/star/container/XNameAccess.hpp>
+#include <com/sun/star/configuration/theDefaultProvider.hpp>
+
+using namespace ::com::sun::star;
+using namespace ::com::sun::star::uno;
+
+namespace sd::slidesorter::cache {
+
+namespace
+{
+    typedef std::shared_ptr<CacheConfiguration> CacheConfigSharedPtr;
+    CacheConfigSharedPtr& theInstance()
+    {
+        static CacheConfigSharedPtr SINGLETON;
+        return SINGLETON;
+    }
+}
+
+std::weak_ptr<CacheConfiguration> CacheConfiguration::mpWeakInstance;
+
+std::shared_ptr<CacheConfiguration> CacheConfiguration::Instance()
+{
+    SolarMutexGuard aSolarGuard;
+    CacheConfigSharedPtr &rInstancePtr = theInstance();
+    if (!rInstancePtr)
+    {
+        // Maybe somebody else kept a previously created instance alive.
+        if ( ! mpWeakInstance.expired())
+            rInstancePtr = std::shared_ptr<CacheConfiguration>(mpWeakInstance);
+        if (!rInstancePtr)
+        {
+            // We have to create a new instance.
+            rInstancePtr.reset(new CacheConfiguration());
+            mpWeakInstance = rInstancePtr;
+            // Prepare to release this instance in the near future.
+            rInstancePtr->m_ReleaseTimer.SetInvokeHandler(
+                LINK(rInstancePtr.get(),CacheConfiguration,TimerCallback));
+            rInstancePtr->m_ReleaseTimer.SetTimeout(5000 /* 5s */);
+            rInstancePtr->m_ReleaseTimer.Start();
+        }
+    }
+    return rInstancePtr;
+}
+
+CacheConfiguration::CacheConfiguration()
+    : m_ReleaseTimer("sd::CacheConfiguration maReleaseTimer")
+{
+    // Get the cache size from configuration.
+    try
+    {
+        // Obtain access to the configuration.
+        Reference<lang::XMultiServiceFactory> xProvider =
+            configuration::theDefaultProvider::get( ::comphelper::getProcessComponentContext() );
+
+        // Obtain access to Impress configuration.
+        Sequence<Any> aCreationArguments(comphelper::InitAnyPropertySequence(
+        {
+            {"nodepath", Any(OUString("/org.openoffice.Office.Impress/"))},
+            {"depth", Any(sal_Int32(-1))}
+        }));
+
+        Reference<XInterface> xRoot (xProvider->createInstanceWithArguments(
+            "com.sun.star.configuration.ConfigurationAccess",
+            aCreationArguments));
+        if ( ! xRoot.is())
+            return;
+        Reference<container::XHierarchicalNameAccess> xHierarchy (xRoot, UNO_QUERY);
+        if ( ! xHierarchy.is())
+            return;
+
+        // Get the node for the slide sorter preview cache.
+        mxCacheNode.set( xHierarchy->getByHierarchicalName("MultiPaneGUI/SlideSorter/PreviewCache"), UNO_QUERY);
+    }
+    catch (RuntimeException &)
+    {
+    }
+    catch (Exception &)
+    {
+    }
+}
+
+Any CacheConfiguration::GetValue (const OUString& rName)
+{
+    Any aResult;
+
+    if (mxCacheNode != nullptr)
+    {
+        try
+        {
+            aResult = mxCacheNode->getByName(rName);
+        }
+        catch (Exception &)
+        {
+        }
+    }
+
+    return aResult;
+}
+
+IMPL_STATIC_LINK_NOARG(CacheConfiguration, TimerCallback, Timer *, void)
+{
+    CacheConfigSharedPtr &rInstancePtr = theInstance();
+    // Release our reference to the instance.
+    rInstancePtr.reset();
+    // note: if there are no other references to the instance, m_ReleaseTimer
+    // will be deleted now
+}
+
+void CacheConfiguration::Shutdown()
+{
+    CacheConfigSharedPtr &rInstancePtr = theInstance();
+    rInstancePtr.reset();
+    assert(mpWeakInstance.expired()); // ensure m_ReleaseTimer is destroyed
+}
+
+} // end of namespace ::sd::slidesorter::cache
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/cache/SlsCacheConfiguration.hxx b/sd/source/ui/slidesorter/cache/SlsCacheConfiguration.hxx
new file mode 100644
index 000000000..d53bcd713
--- /dev/null
+++ b/sd/source/ui/slidesorter/cache/SlsCacheConfiguration.hxx
@@ -0,0 +1,68 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <com/sun/star/uno/Any.hxx>
+#include <vcl/timer.hxx>
+#include <memory>
+
+namespace com::sun::star::container
+{
+class XNameAccess;
+}
+
+namespace sd::slidesorter::cache
+{
+/** A very simple and easy-to-use access to configuration entries regarding
+    the slide sorter cache.
+*/
+class CacheConfiguration
+{
+public:
+    /** Return an instance to this class.  The reference is released after 5
+        seconds.  Subsequent calls to this function will create a new
+        instance.
+    */
+    static std::shared_ptr<CacheConfiguration> Instance();
+
+    static void Shutdown();
+
+    /** Look up the specified value in
+        MultiPaneGUI/SlideSorter/PreviewCache.   When the specified value
+        does not exist then an empty Any is returned.
+    */
+    css::uno::Any GetValue(const OUString& rName);
+
+private:
+    /** When a caller holds a reference after we have released ours we use
+        this weak pointer to avoid creating a new instance.
+    */
+    static std::weak_ptr<CacheConfiguration> mpWeakInstance;
+    Timer m_ReleaseTimer;
+    css::uno::Reference<css::container::XNameAccess> mxCacheNode;
+
+    CacheConfiguration();
+
+    DECL_STATIC_LINK(CacheConfiguration, TimerCallback, Timer*, void);
+};
+
+} // end of namespace ::sd::slidesorter::cache
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/cache/SlsGenericPageCache.cxx b/sd/source/ui/slidesorter/cache/SlsGenericPageCache.cxx
new file mode 100644
index 000000000..6275754fa
--- /dev/null
+++ b/sd/source/ui/slidesorter/cache/SlsGenericPageCache.cxx
@@ -0,0 +1,278 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "SlsGenericPageCache.hxx"
+
+#include "SlsQueueProcessor.hxx"
+#include "SlsRequestPriorityClass.hxx"
+#include "SlsRequestFactory.hxx"
+#include "SlsBitmapCache.hxx"
+#include <cache/SlsPageCacheManager.hxx>
+#include <tools/debug.hxx>
+
+namespace sd::slidesorter::cache {
+
+GenericPageCache::GenericPageCache (
+    const Size& rPreviewSize,
+    const bool bDoSuperSampling,
+    const SharedCacheContext& rpCacheContext)
+    : maRequestQueue(rpCacheContext),
+      mpCacheContext(rpCacheContext),
+      maPreviewSize(rPreviewSize),
+      mbDoSuperSampling(bDoSuperSampling)
+{
+    // A large size may indicate an error of the caller.  After all we
+    // are creating previews.
+        DBG_ASSERT (maPreviewSize.Width()<1000 && maPreviewSize.Height()<1000,
+        "GenericPageCache<>::GetPreviewBitmap(): bitmap requested with large width. "
+        "This may indicate an error.");
+}
+
+GenericPageCache::~GenericPageCache()
+{
+    if (mpQueueProcessor != nullptr)
+        mpQueueProcessor->Stop();
+    maRequestQueue.Clear();
+    mpQueueProcessor.reset();
+
+    if (mpBitmapCache != nullptr)
+        PageCacheManager::Instance()->ReleaseCache(mpBitmapCache);
+    mpBitmapCache.reset();
+}
+
+void GenericPageCache::ProvideCacheAndProcessor()
+{
+    if (mpBitmapCache == nullptr)
+        mpBitmapCache = PageCacheManager::Instance()->GetCache(
+            mpCacheContext->GetModel(),
+            maPreviewSize);
+
+    if (mpQueueProcessor == nullptr)
+        mpQueueProcessor.reset(new QueueProcessor(
+            maRequestQueue,
+            mpBitmapCache,
+            maPreviewSize,
+            mbDoSuperSampling,
+            mpCacheContext));
+}
+
+void GenericPageCache::ChangePreviewSize (
+    const Size& rPreviewSize,
+    const bool bDoSuperSampling)
+{
+    if (rPreviewSize==maPreviewSize && bDoSuperSampling==mbDoSuperSampling)
+        return;
+
+    // A large size may indicate an error of the caller.  After all we
+    // are creating previews.
+    DBG_ASSERT (maPreviewSize.Width()<1000 && maPreviewSize.Height()<1000,
+        "GenericPageCache<>::GetPreviewBitmap(): bitmap requested with large width. "
+        "This may indicate an error.");
+
+    if (mpBitmapCache != nullptr)
+    {
+        mpBitmapCache = PageCacheManager::Instance()->ChangeSize(
+            mpBitmapCache, maPreviewSize, rPreviewSize);
+        if (mpQueueProcessor != nullptr)
+        {
+            mpQueueProcessor->SetPreviewSize(rPreviewSize, bDoSuperSampling);
+            mpQueueProcessor->SetBitmapCache(mpBitmapCache);
+        }
+    }
+    maPreviewSize = rPreviewSize;
+    mbDoSuperSampling = bDoSuperSampling;
+}
+
+BitmapEx GenericPageCache::GetPreviewBitmap (
+    const CacheKey aKey,
+    const bool bResize)
+{
+    assert(aKey != nullptr);
+
+    BitmapEx aPreview;
+    bool bMayBeUpToDate = true;
+    ProvideCacheAndProcessor();
+    const SdrPage* pPage = mpCacheContext->GetPage(aKey);
+    if (mpBitmapCache->HasBitmap(pPage))
+    {
+        aPreview = mpBitmapCache->GetBitmap(pPage);
+        const Size aBitmapSize (aPreview.GetSizePixel());
+        if (aBitmapSize != maPreviewSize)
+        {
+            // Scale the bitmap to the desired size when that is possible,
+            // i.e. the bitmap is not empty.
+            if (bResize && !aBitmapSize.IsEmpty())
+            {
+                aPreview.Scale(maPreviewSize);
+            }
+            bMayBeUpToDate = false;
+        }
+        else
+            bMayBeUpToDate = true;
+    }
+    else
+        bMayBeUpToDate = false;
+
+    // Request the creation of a correctly sized preview bitmap.  We do this
+    // even when the size of the bitmap in the cache is correct because its
+    // content may be not up-to-date anymore.
+    RequestPreviewBitmap(aKey, bMayBeUpToDate);
+
+    return aPreview;
+}
+
+BitmapEx GenericPageCache::GetMarkedPreviewBitmap (
+    const CacheKey aKey)
+{
+    assert(aKey != nullptr);
+
+    ProvideCacheAndProcessor();
+    const SdrPage* pPage = mpCacheContext->GetPage(aKey);
+    BitmapEx aMarkedPreview (mpBitmapCache->GetMarkedBitmap(pPage));
+
+    return aMarkedPreview;
+}
+
+void GenericPageCache::SetMarkedPreviewBitmap (
+    const CacheKey aKey,
+    const BitmapEx& rMarkedBitmap)
+{
+    assert(aKey != nullptr);
+
+    ProvideCacheAndProcessor();
+    const SdrPage* pPage = mpCacheContext->GetPage(aKey);
+    mpBitmapCache->SetMarkedBitmap(pPage, rMarkedBitmap);
+}
+
+void GenericPageCache::RequestPreviewBitmap (
+    const CacheKey aKey,
+    const bool bMayBeUpToDate)
+{
+    assert(aKey != nullptr);
+
+    const SdrPage* pPage = mpCacheContext->GetPage(aKey);
+
+    ProvideCacheAndProcessor();
+
+    // Determine if the available bitmap is up to date.
+    bool bIsUpToDate = false;
+    if (bMayBeUpToDate)
+        bIsUpToDate = mpBitmapCache->BitmapIsUpToDate (pPage);
+    if (bIsUpToDate)
+    {
+        const BitmapEx aPreview (mpBitmapCache->GetBitmap(pPage));
+        if (aPreview.IsEmpty() || aPreview.GetSizePixel()!=maPreviewSize)
+              bIsUpToDate = false;
+    }
+
+    if (  bIsUpToDate)
+        return;
+
+    // No, the bitmap is not up-to-date.  Request a new one.
+    RequestPriorityClass ePriorityClass (NOT_VISIBLE);
+    if (mpCacheContext->IsVisible(aKey))
+    {
+        if (mpBitmapCache->HasBitmap(pPage))
+            ePriorityClass = VISIBLE_OUTDATED_PREVIEW;
+        else
+            ePriorityClass = VISIBLE_NO_PREVIEW;
+    }
+    maRequestQueue.AddRequest(aKey, ePriorityClass);
+    mpQueueProcessor->Start(ePriorityClass);
+}
+
+bool GenericPageCache::InvalidatePreviewBitmap (const CacheKey aKey)
+{
+    // Invalidate the page in all caches that reference it, not just this one.
+    std::shared_ptr<cache::PageCacheManager> pCacheManager (
+        cache::PageCacheManager::Instance());
+    if (pCacheManager)
+        return pCacheManager->InvalidatePreviewBitmap(
+            mpCacheContext->GetModel(),
+            aKey);
+    else if (mpBitmapCache != nullptr)
+        return mpBitmapCache->InvalidateBitmap(mpCacheContext->GetPage(aKey));
+    else
+        return false;
+}
+
+void GenericPageCache::InvalidateCache ()
+{
+    if (!mpBitmapCache)
+        return;
+
+    // When the cache is being invalidated then it makes no sense to
+    // continue creating preview bitmaps.  However, this may be
+    // re-started below.
+    mpQueueProcessor->Stop();
+    maRequestQueue.Clear();
+
+    // Mark the previews in the cache as not being up-to-date anymore.
+    // Depending on the given bUpdateCache flag we start to create new
+    // preview bitmaps.
+    mpBitmapCache->InvalidateCache();
+    RequestFactory()(maRequestQueue, mpCacheContext);
+}
+
+void GenericPageCache::SetPreciousFlag (
+    const CacheKey aKey,
+    const bool bIsPrecious)
+{
+    ProvideCacheAndProcessor();
+
+    // Change the request priority class according to the new precious flag.
+    if (bIsPrecious)
+    {
+        if (mpBitmapCache->HasBitmap(mpCacheContext->GetPage(aKey)))
+            maRequestQueue.ChangeClass(aKey,VISIBLE_OUTDATED_PREVIEW);
+        else
+            maRequestQueue.ChangeClass(aKey,VISIBLE_NO_PREVIEW);
+    }
+    else
+    {
+        if (mpBitmapCache->IsFull())
+        {
+            // When the bitmap cache is full then requests for slides that
+            // are not visible are removed.
+            maRequestQueue.RemoveRequest(aKey);
+        }
+        else
+            maRequestQueue.ChangeClass(aKey,NOT_VISIBLE);
+    }
+
+    mpBitmapCache->SetPrecious(mpCacheContext->GetPage(aKey), bIsPrecious);
+}
+
+void GenericPageCache::Pause()
+{
+    ProvideCacheAndProcessor();
+    if (mpQueueProcessor != nullptr)
+        mpQueueProcessor->Pause();
+}
+
+void GenericPageCache::Resume()
+{
+    ProvideCacheAndProcessor();
+    if (mpQueueProcessor != nullptr)
+        mpQueueProcessor->Resume();
+}
+
+} // end of namespace ::sd::slidesorter::cache
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/cache/SlsGenericPageCache.hxx b/sd/source/ui/slidesorter/cache/SlsGenericPageCache.hxx
new file mode 100644
index 000000000..900d40268
--- /dev/null
+++ b/sd/source/ui/slidesorter/cache/SlsGenericPageCache.hxx
@@ -0,0 +1,152 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include "SlsRequestQueue.hxx"
+#include <memory>
+
+#include <vcl/bitmapex.hxx>
+
+namespace sd::slidesorter::cache {
+
+class BitmapCache;
+class QueueProcessor;
+
+/** This basically is the implementation class for the PageCache class.
+*/
+class GenericPageCache
+{
+public:
+    /** The page cache is created with a reference to the SlideSorter and
+        thus has access to both view and model.  This allows the cache to
+        fill itself with requests for all pages or just the visible ones.
+        @param rPreviewSize
+            The size of the previews is expected in pixel values.
+        @param bDoSuperSampling
+            When <TRUE/> the previews are rendered larger and then scaled
+            down to the requested size to improve image quality.
+    */
+    GenericPageCache (
+        const Size& rPreviewSize,
+        const bool bDoSuperSampling,
+        const SharedCacheContext& rpCacheContext);
+
+    ~GenericPageCache();
+
+    /** Change the size of the preview bitmaps.  This may be caused by a
+        resize of the slide sorter window or a change of the number of
+        columns.
+    */
+    void ChangePreviewSize (
+        const Size& rPreviewSize,
+        const bool bDoSuperSampling);
+
+    /** Request a preview bitmap for the specified page object in the
+        specified size.  The returned bitmap may be a preview of the preview,
+        i.e. either a scaled (up or down) version of a previous preview (of
+        the wrong size) or an empty bitmap.  In this case a request for the
+        generation of a new preview is created and inserted into the request
+        queue.  When the preview is available the page shape will be told to
+        paint itself again.  When it then calls this method again if
+        receives the correctly sized preview bitmap.
+        @param rRequestData
+            This data is used to determine the preview.
+        @param bResize
+            When <TRUE/> then when the available bitmap has not the
+            requested size, it is scaled before it is returned.  When
+            <FALSE/> then the bitmap is returned in the wrong size and it is
+            the task of the caller to scale it.
+        @return
+            Returns a bitmap that is either empty, contains a scaled (up or
+            down) version or is the requested bitmap.
+    */
+    BitmapEx GetPreviewBitmap (
+        const CacheKey aKey,
+        const bool bResize);
+    BitmapEx GetMarkedPreviewBitmap (
+        const CacheKey aKey);
+    void SetMarkedPreviewBitmap (
+        const CacheKey aKey,
+        const BitmapEx& rMarkedBitmap);
+
+    /** When the requested preview bitmap does not yet exist or is not
+        up-to-date then the rendering of one is scheduled.  Otherwise this
+        method does nothing.
+        @param rRequestData
+            This data is used to determine the preview.
+        @param bMayBeUpToDate
+            This flag helps the method to determine whether an existing
+            preview that matches the request is up to date.  If the caller
+            knows that it is not then by passing <FALSE/> he tells us that we
+            do not have to check the up-to-date flag a second time.  If
+            unsure use <TRUE/>.
+    */
+    void RequestPreviewBitmap (
+        const CacheKey aKey,
+        const bool bMayBeUpToDate);
+
+    /** Tell the cache to replace the bitmap associated with the given
+        request data with a new one that reflects recent changes in the
+        content of the page object.
+        @return
+            When the key is known then return <TRUE/>.
+    */
+    bool InvalidatePreviewBitmap (const CacheKey aKey);
+
+    /** Call this method when all preview bitmaps have to be generated anew.
+        This is the case when the size of the page objects on the screen has
+        changed or when the model has changed.
+    */
+    void InvalidateCache ();
+
+    /** With the precious flag you can control whether a bitmap can be
+        removed from the cache or reduced in size to make room for other
+        bitmaps or is so precious that it will not be touched.  A typical
+        use is to set the precious flag for the visible pages.
+    */
+    void SetPreciousFlag (const CacheKey aKey, const bool bIsPrecious);
+
+    void Pause();
+    void Resume();
+
+private:
+    std::shared_ptr<BitmapCache> mpBitmapCache;
+
+    RequestQueue maRequestQueue;
+
+    std::unique_ptr<QueueProcessor> mpQueueProcessor;
+
+    SharedCacheContext mpCacheContext;
+
+    /** The current size of preview bitmaps.
+    */
+    Size maPreviewSize;
+
+    bool mbDoSuperSampling;
+
+    /** Both bitmap cache and queue processor are created on demand by this
+        method.
+    */
+    void ProvideCacheAndProcessor();
+};
+
+} // end of namespace ::sd::slidesorter::cache
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/cache/SlsPageCache.cxx b/sd/source/ui/slidesorter/cache/SlsPageCache.cxx
new file mode 100644
index 000000000..82b1b8ae4
--- /dev/null
+++ b/sd/source/ui/slidesorter/cache/SlsPageCache.cxx
@@ -0,0 +1,109 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <tools/gen.hxx>
+#include "SlsGenericPageCache.hxx"
+#include <cache/SlsPageCache.hxx>
+
+using namespace ::com::sun::star;
+
+namespace sd::slidesorter::cache {
+
+//===== PageCache =============================================================
+
+PageCache::PageCache (
+    const Size& rPreviewSize,
+    const bool bDoSuperSampling,
+    const SharedCacheContext& rpCacheContext)
+   : mpImplementation(
+        new GenericPageCache(
+            rPreviewSize,
+            bDoSuperSampling,
+            rpCacheContext))
+{
+}
+
+PageCache::~PageCache()
+{
+}
+
+void PageCache::ChangeSize (
+    const Size& rPreviewSize,
+    const bool bDoSuperSampling)
+{
+    mpImplementation->ChangePreviewSize(rPreviewSize, bDoSuperSampling);
+}
+
+BitmapEx PageCache::GetPreviewBitmap (
+    const CacheKey aKey,
+    const bool bResize)
+{
+    return mpImplementation->GetPreviewBitmap(aKey, bResize);
+}
+
+BitmapEx PageCache::GetMarkedPreviewBitmap (
+    const CacheKey aKey)
+{
+    return mpImplementation->GetMarkedPreviewBitmap(aKey);
+}
+
+void PageCache::SetMarkedPreviewBitmap (
+    const CacheKey aKey,
+    const BitmapEx& rMarkedBitmap)
+{
+    mpImplementation->SetMarkedPreviewBitmap(aKey, rMarkedBitmap);
+}
+
+void PageCache::RequestPreviewBitmap (const CacheKey aKey)
+{
+    return mpImplementation->RequestPreviewBitmap(aKey, true);
+}
+
+void PageCache::InvalidatePreviewBitmap (
+    const CacheKey aKey)
+{
+    if (mpImplementation->InvalidatePreviewBitmap(aKey))
+        RequestPreviewBitmap(aKey);
+}
+
+void PageCache::InvalidateCache()
+{
+    mpImplementation->InvalidateCache();
+}
+
+void PageCache::SetPreciousFlag (
+    const CacheKey aKey,
+    const bool bIsPrecious)
+{
+    mpImplementation->SetPreciousFlag(aKey, bIsPrecious);
+}
+
+void PageCache::Pause()
+{
+    mpImplementation->Pause();
+}
+
+void PageCache::Resume()
+{
+    mpImplementation->Resume();
+}
+
+} // end of namespace ::sd::slidesorter::cache
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/cache/SlsPageCacheManager.cxx b/sd/source/ui/slidesorter/cache/SlsPageCacheManager.cxx
new file mode 100644
index 000000000..45afd93c9
--- /dev/null
+++ b/sd/source/ui/slidesorter/cache/SlsPageCacheManager.cxx
@@ -0,0 +1,420 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <cache/SlsPageCacheManager.hxx>
+
+#include "SlsBitmapCache.hxx"
+
+#include <deque>
+#include <map>
+#include <memory>
+#include <unordered_map>
+
+namespace {
+
+/** Collection of data that is stored for all active preview caches.
+*/
+class CacheDescriptor
+{
+public:
+    ::sd::slidesorter::cache::PageCacheManager::DocumentKey mpDocument;
+    Size maPreviewSize;
+
+    CacheDescriptor(
+        ::sd::slidesorter::cache::PageCacheManager::DocumentKey const & pDocument,
+        const Size& rPreviewSize)
+        :mpDocument(pDocument),maPreviewSize(rPreviewSize)
+    {}
+    /// Test for equality with respect to all members.
+    class Equal {public: bool operator() (
+        const CacheDescriptor& rDescriptor1, const CacheDescriptor& rDescriptor2) const {
+        return rDescriptor1.mpDocument==rDescriptor2.mpDocument
+            && rDescriptor1.maPreviewSize==rDescriptor2.maPreviewSize;
+    } };
+    /// Hash function that takes all members into account.
+    class Hash {public: size_t operator() (const CacheDescriptor& rDescriptor) const {
+        return reinterpret_cast<size_t>(rDescriptor.mpDocument.get()) + rDescriptor.maPreviewSize.Width();
+    } };
+};
+
+/** Collection of data that is stored for the inactive, recently used
+    caches.
+*/
+class RecentlyUsedCacheDescriptor
+{
+public:
+    Size maPreviewSize;
+    std::shared_ptr< ::sd::slidesorter::cache::BitmapCache> mpCache;
+
+    RecentlyUsedCacheDescriptor(
+        const Size& rPreviewSize,
+        const std::shared_ptr< ::sd::slidesorter::cache::BitmapCache>& rpCache)
+        :maPreviewSize(rPreviewSize),mpCache(rpCache)
+    {}
+};
+
+/** The list of recently used caches is organized as queue.  When elements
+    are added the list is shortened to the maximally allowed number of
+    elements by removing the least recently used elements.
+*/
+typedef ::std::deque<RecentlyUsedCacheDescriptor> RecentlyUsedQueue;
+
+/** Compare the caches by preview size.  Those that match the given size
+    come first, then, regardless of the given size, the largest ones before
+    the smaller ones.
+*/
+class BestFittingCacheComparer
+{
+public:
+    explicit BestFittingCacheComparer (const Size& rPreferredSize)
+        : maPreferredSize(rPreferredSize)
+    {}
+    bool operator()(const ::sd::slidesorter::cache::PageCacheManager::BestFittingPageCaches::value_type& rElement1,
+        const ::sd::slidesorter::cache::PageCacheManager::BestFittingPageCaches::value_type& rElement2)
+    {
+        if (rElement2.first == maPreferredSize)
+            return false;
+        else if (rElement1.first == maPreferredSize)
+            return true;
+        else
+            return (rElement1.first.Width()*rElement1.first.Height()
+                > rElement2.first.Width()*rElement2.first.Height());
+    }
+
+private:
+    Size maPreferredSize;
+};
+
+} // end of anonymous namespace
+
+namespace sd::slidesorter::cache {
+
+/** Container for the active caches.
+*/
+class PageCacheManager::PageCacheContainer
+    : public std::unordered_map<CacheDescriptor,
+                             std::shared_ptr<BitmapCache>,
+                             CacheDescriptor::Hash,
+                             CacheDescriptor::Equal>
+{
+public:
+    PageCacheContainer() {}
+
+    /** Compare entries in the cache container with respect to the cache
+        address only.
+    */
+    class CompareWithCache { public:
+        explicit CompareWithCache(const std::shared_ptr<BitmapCache>& rpCache)
+            : mpCache(rpCache) {}
+        bool operator () (const PageCacheContainer::value_type& rValue) const
+        { return rValue.second == mpCache; }
+    private:
+        std::shared_ptr<BitmapCache> mpCache;
+    };
+};
+
+/** The recently used caches are stored in one queue for each document.
+*/
+class PageCacheManager::RecentlyUsedPageCaches
+{
+public:
+    typedef DocumentKey                                 key_type;
+    typedef RecentlyUsedQueue                           mapped_type;
+    typedef std::map<key_type,mapped_type>::iterator    iterator;
+private:
+    std::map<key_type,mapped_type> maMap;
+public:
+    RecentlyUsedPageCaches () {};
+
+    iterator end() { return maMap.end(); }
+    void clear() { maMap.clear(); }
+    iterator find(const key_type& key) { return maMap.find(key); }
+    template<class... Args>
+    std::pair<iterator,bool> emplace(Args&&... args) { return maMap.emplace(std::forward<Args>(args)...); }
+};
+
+class PageCacheManager::Deleter
+{
+public:
+    void operator() (PageCacheManager* pObject) { delete pObject; }
+};
+
+//===== PageCacheManager ====================================================
+
+std::weak_ptr<PageCacheManager> PageCacheManager::mpInstance;
+
+std::shared_ptr<PageCacheManager> PageCacheManager::Instance()
+{
+    std::shared_ptr<PageCacheManager> pInstance;
+
+    ::osl::MutexGuard aGuard (::osl::Mutex::getGlobalMutex());
+
+    pInstance = mpInstance.lock();
+    if (pInstance == nullptr)
+    {
+        pInstance = std::shared_ptr<PageCacheManager>(
+            new PageCacheManager(),
+            PageCacheManager::Deleter());
+        mpInstance = pInstance;
+    }
+
+    return pInstance;
+}
+
+PageCacheManager::PageCacheManager()
+    : mpPageCaches(new PageCacheContainer()),
+      mpRecentlyUsedPageCaches(new RecentlyUsedPageCaches())
+{
+}
+
+PageCacheManager::~PageCacheManager()
+{
+}
+
+std::shared_ptr<BitmapCache> PageCacheManager::GetCache (
+    const DocumentKey& pDocument,
+    const Size& rPreviewSize)
+{
+    std::shared_ptr<BitmapCache> pResult;
+
+    // Look for the cache in the list of active caches.
+    CacheDescriptor aKey (pDocument, rPreviewSize);
+    PageCacheContainer::iterator iCache (mpPageCaches->find(aKey));
+    if (iCache != mpPageCaches->end())
+        pResult = iCache->second;
+
+    // Look for the cache in the list of recently used caches.
+    if (pResult == nullptr)
+        pResult = GetRecentlyUsedCache(pDocument, rPreviewSize);
+
+    // Create the cache when no suitable one does exist.
+    if (pResult == nullptr)
+        pResult = std::make_shared<BitmapCache>();
+
+    // The cache may be newly created and thus empty or is old and may
+    // contain previews that are not up-to-date.  Recycle previews from
+    // other caches to fill in the holes.
+    Recycle(pResult, pDocument,rPreviewSize);
+
+    // Put the new (or old) cache into the container.
+    mpPageCaches->emplace(aKey, pResult);
+
+    return pResult;
+}
+
+void PageCacheManager::Recycle (
+    const std::shared_ptr<BitmapCache>& rpCache,
+    const DocumentKey& pDocument,
+    const Size& rPreviewSize)
+{
+    BestFittingPageCaches aCaches;
+
+    // Add bitmap caches from active caches.
+    for (auto& rActiveCache : *mpPageCaches)
+    {
+        if (rActiveCache.first.mpDocument == pDocument)
+            aCaches.emplace_back(
+                rActiveCache.first.maPreviewSize, rActiveCache.second);
+    }
+
+    // Add bitmap caches from recently used caches.
+    RecentlyUsedPageCaches::iterator iQueue (mpRecentlyUsedPageCaches->find(pDocument));
+    if (iQueue != mpRecentlyUsedPageCaches->end())
+    {
+        for (const auto& rRecentCache : iQueue->second)
+            aCaches.emplace_back(
+                rRecentCache.maPreviewSize, rRecentCache.mpCache);
+    }
+
+    ::std::sort(aCaches.begin(), aCaches.end(), BestFittingCacheComparer(rPreviewSize));
+
+    for (const auto& rBestCache : aCaches)
+    {
+        rpCache->Recycle(*rBestCache.second);
+    }
+}
+
+void PageCacheManager::ReleaseCache (const std::shared_ptr<BitmapCache>& rpCache)
+{
+    PageCacheContainer::iterator iCache (::std::find_if(
+        mpPageCaches->begin(),
+        mpPageCaches->end(),
+        PageCacheContainer::CompareWithCache(rpCache)));
+
+    if (iCache != mpPageCaches->end())
+    {
+        assert(iCache->second == rpCache);
+
+        PutRecentlyUsedCache(iCache->first.mpDocument,iCache->first.maPreviewSize,rpCache);
+
+        mpPageCaches->erase(iCache);
+    }
+}
+
+std::shared_ptr<BitmapCache> PageCacheManager::ChangeSize (
+    const std::shared_ptr<BitmapCache>& rpCache,
+    const Size&,
+    const Size& rNewPreviewSize)
+{
+    std::shared_ptr<BitmapCache> pResult;
+
+    if (rpCache != nullptr)
+    {
+        // Look up the given cache in the list of active caches.
+        PageCacheContainer::iterator iCacheToChange (::std::find_if(
+            mpPageCaches->begin(),
+            mpPageCaches->end(),
+            PageCacheContainer::CompareWithCache(rpCache)));
+        if (iCacheToChange != mpPageCaches->end())
+        {
+            assert(iCacheToChange->second == rpCache);
+
+            // Now, we can change the preview size of the existing one by
+            // removing the cache from the list and re-insert it with the
+            // updated size.
+            const ::sd::slidesorter::cache::PageCacheManager::DocumentKey aKey (
+                iCacheToChange->first.mpDocument);
+            mpPageCaches->erase(iCacheToChange);
+            mpPageCaches->emplace(
+                CacheDescriptor(aKey,rNewPreviewSize),
+                rpCache);
+
+            pResult = rpCache;
+        }
+        else
+        {
+            assert(iCacheToChange != mpPageCaches->end());
+        }
+    }
+
+    return pResult;
+}
+
+bool PageCacheManager::InvalidatePreviewBitmap (
+    const  DocumentKey& pDocument,
+    const SdrPage* pKey)
+{
+    bool bHasChanged (false);
+
+    if (pDocument!=nullptr)
+    {
+        // Iterate over all caches that are currently in use and invalidate
+        // the previews in those that belong to the document.
+        for (auto& rCache : *mpPageCaches)
+            if (rCache.first.mpDocument == pDocument)
+                bHasChanged |= rCache.second->InvalidateBitmap(pKey);
+
+        // Invalidate the previews in the recently used caches belonging to
+        // the given document.
+        RecentlyUsedPageCaches::iterator iQueue (mpRecentlyUsedPageCaches->find(pDocument));
+        if (iQueue != mpRecentlyUsedPageCaches->end())
+        {
+            for (const auto& rCache2 : iQueue->second)
+                bHasChanged |= rCache2.mpCache->InvalidateBitmap(pKey);
+        }
+    }
+
+    return bHasChanged;
+}
+
+void PageCacheManager::InvalidateAllPreviewBitmaps (const DocumentKey& pDocument)
+{
+    if (pDocument == nullptr)
+        return;
+
+    // Iterate over all caches that are currently in use and invalidate the
+    // previews in those that belong to the document.
+    for (auto& rCache : *mpPageCaches)
+        if (rCache.first.mpDocument == pDocument)
+            rCache.second->InvalidateCache();
+
+    // Invalidate the previews in the recently used caches belonging to the
+    // given document.
+    RecentlyUsedPageCaches::iterator iQueue (mpRecentlyUsedPageCaches->find(pDocument));
+    if (iQueue != mpRecentlyUsedPageCaches->end())
+    {
+        for (const auto& rCache2 : iQueue->second)
+            rCache2.mpCache->InvalidateCache();
+    }
+}
+
+void PageCacheManager::InvalidateAllCaches()
+{
+    // Iterate over all caches that are currently in use and invalidate
+    // them.
+    for (auto& rCache : *mpPageCaches)
+        rCache.second->InvalidateCache();
+
+    // Remove all recently used caches, there is not much sense in storing
+    // invalidated and unused caches.
+    mpRecentlyUsedPageCaches->clear();
+}
+
+void PageCacheManager::ReleasePreviewBitmap (const SdrPage* pPage)
+{
+    for (auto& rCache : *mpPageCaches)
+        rCache.second->ReleaseBitmap(pPage);
+}
+
+std::shared_ptr<BitmapCache> PageCacheManager::GetRecentlyUsedCache (
+    const DocumentKey& pDocument,
+    const Size& rPreviewSize)
+{
+    std::shared_ptr<BitmapCache> pCache;
+
+    // Look for the cache in the list of recently used caches.
+    RecentlyUsedPageCaches::iterator iQueue (mpRecentlyUsedPageCaches->find(pDocument));
+    if (iQueue != mpRecentlyUsedPageCaches->end())
+    {
+        RecentlyUsedQueue::iterator iCache = std::find_if(iQueue->second.begin(), iQueue->second.end(),
+            [&rPreviewSize](const RecentlyUsedCacheDescriptor& rCache) { return rCache.maPreviewSize == rPreviewSize; });
+        if (iCache != iQueue->second.end())
+        {
+            pCache = iCache->mpCache;
+            iQueue->second.erase(iCache);
+        }
+    }
+
+    return pCache;
+}
+
+void PageCacheManager::PutRecentlyUsedCache(
+    DocumentKey const & pDocument,
+    const Size& rPreviewSize,
+    const std::shared_ptr<BitmapCache>& rpCache)
+{
+    // Look up the list of recently used caches for the given document.
+    RecentlyUsedPageCaches::iterator iQueue (mpRecentlyUsedPageCaches->find(pDocument));
+    if (iQueue == mpRecentlyUsedPageCaches->end())
+        iQueue = mpRecentlyUsedPageCaches->emplace(
+            pDocument, RecentlyUsedQueue()
+            ).first;
+
+    if (iQueue != mpRecentlyUsedPageCaches->end())
+    {
+        iQueue->second.push_front(RecentlyUsedCacheDescriptor(rPreviewSize,rpCache));
+        // Shorten the list of recently used caches to the allowed maximal length.
+        while (iQueue->second.size() > mnMaximalRecentlyCacheCount)
+            iQueue->second.pop_back();
+    }
+}
+
+} // end of namespace ::sd::slidesorter::cache
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/cache/SlsQueueProcessor.cxx b/sd/source/ui/slidesorter/cache/SlsQueueProcessor.cxx
new file mode 100644
index 000000000..077c48709
--- /dev/null
+++ b/sd/source/ui/slidesorter/cache/SlsQueueProcessor.cxx
@@ -0,0 +1,176 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "SlsQueueProcessor.hxx"
+#include "SlsRequestQueue.hxx"
+#include "SlsBitmapCache.hxx"
+
+#include <sdpage.hxx>
+#include <comphelper/profilezone.hxx>
+#include <tools/diagnose_ex.h>
+
+namespace sd::slidesorter::cache {
+
+//=====  QueueProcessor  ======================================================
+
+QueueProcessor::QueueProcessor (
+    RequestQueue& rQueue,
+    const std::shared_ptr<BitmapCache>& rpCache,
+    const Size& rPreviewSize,
+    const bool bDoSuperSampling,
+    const SharedCacheContext& rpCacheContext)
+    : maTimer("sd::QueueProcessor maTimer"),
+      maPreviewSize(rPreviewSize),
+      mbDoSuperSampling(bDoSuperSampling),
+      mpCacheContext(rpCacheContext),
+      mrQueue(rQueue),
+      mpCache(rpCache),
+      mbIsPaused(false)
+{
+    maTimer.SetInvokeHandler (LINK(this,QueueProcessor,ProcessRequestHdl));
+    maTimer.SetTimeout (10);
+}
+
+QueueProcessor::~QueueProcessor()
+{
+}
+
+void QueueProcessor::Start (int nPriorityClass)
+{
+    if (mbIsPaused)
+        return;
+    if ( ! maTimer.IsActive())
+    {
+        if (nPriorityClass == 0)
+            maTimer.SetTimeout (10);
+        else
+            maTimer.SetTimeout (100);
+        maTimer.Start();
+    }
+}
+
+void QueueProcessor::Stop()
+{
+    if (maTimer.IsActive())
+        maTimer.Stop();
+}
+
+void QueueProcessor::Pause()
+{
+    mbIsPaused = true;
+}
+
+void QueueProcessor::Resume()
+{
+    mbIsPaused = false;
+    if ( ! mrQueue.IsEmpty())
+        Start(mrQueue.GetFrontPriorityClass());
+}
+
+void QueueProcessor::SetPreviewSize (
+    const Size& rPreviewSize,
+    const bool bDoSuperSampling)
+{
+    maPreviewSize = rPreviewSize;
+    mbDoSuperSampling = bDoSuperSampling;
+}
+
+IMPL_LINK_NOARG(QueueProcessor, ProcessRequestHdl, Timer *, void)
+{
+    ProcessRequests();
+}
+
+void QueueProcessor::ProcessRequests()
+{
+    assert(mpCacheContext);
+
+    // Never process more than one request at a time in order to prevent the
+    // lock up of the edit view.
+    if ( ! mrQueue.IsEmpty()
+        && ! mbIsPaused
+        &&  mpCacheContext->IsIdle())
+    {
+        CacheKey aKey = nullptr;
+        RequestPriorityClass ePriorityClass (NOT_VISIBLE);
+        {
+            ::osl::MutexGuard aGuard (mrQueue.GetMutex());
+
+            if ( ! mrQueue.IsEmpty())
+            {
+                // Get the request with the highest priority from the queue.
+                ePriorityClass = mrQueue.GetFrontPriorityClass();
+                aKey = mrQueue.GetFront();
+                mrQueue.PopFront();
+            }
+        }
+
+        if (aKey != nullptr)
+            ProcessOneRequest(aKey, ePriorityClass);
+    }
+
+    // Schedule the processing of the next element(s).
+    {
+        ::osl::MutexGuard aGuard (mrQueue.GetMutex());
+        if ( ! mrQueue.IsEmpty())
+            Start(mrQueue.GetFrontPriorityClass());
+        else
+        {
+            comphelper::ProfileZone aZone("QueueProcessor finished processing all elements");
+        }
+    }
+}
+
+void QueueProcessor::ProcessOneRequest (
+    CacheKey aKey,
+    const RequestPriorityClass ePriorityClass)
+{
+    try
+    {
+        std::scoped_lock aGuard (maMutex);
+
+        // Create a new preview bitmap and store it in the cache.
+        if (mpCache != nullptr && mpCacheContext)
+        {
+            const SdPage* pSdPage = dynamic_cast<const SdPage*>(mpCacheContext->GetPage(aKey));
+            if (pSdPage != nullptr)
+            {
+                const BitmapEx aPreview (
+                    maBitmapFactory.CreateBitmap(*pSdPage, maPreviewSize, mbDoSuperSampling));
+                mpCache->SetBitmap (pSdPage, aPreview, ePriorityClass!=NOT_VISIBLE);
+
+                // Initiate a repaint of the new preview.
+                mpCacheContext->NotifyPreviewCreation(aKey);
+            }
+        }
+    }
+    catch (css::uno::Exception &)
+    {
+        TOOLS_WARN_EXCEPTION( "sd", "QueueProcessor");
+    }
+}
+
+void QueueProcessor::SetBitmapCache (
+    const std::shared_ptr<BitmapCache>& rpCache)
+{
+    mpCache = rpCache;
+}
+
+} // end of namespace ::sd::slidesorter::cache
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/cache/SlsQueueProcessor.hxx b/sd/source/ui/slidesorter/cache/SlsQueueProcessor.hxx
new file mode 100644
index 000000000..0035bcbce
--- /dev/null
+++ b/sd/source/ui/slidesorter/cache/SlsQueueProcessor.hxx
@@ -0,0 +1,98 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <cache/SlsCacheContext.hxx>
+#include "SlsRequestPriorityClass.hxx"
+#include "SlsBitmapFactory.hxx"
+
+#include <vcl/timer.hxx>
+#include <mutex>
+
+namespace sd::slidesorter::cache {
+
+class BitmapCache;
+class RequestQueue;
+
+/** This queue processor is timer based, i.e. when an entry is added to the
+    queue and the processor is started with Start() in the base class a
+    timer is started that eventually calls ProcessRequest().  This is
+    repeated until the queue is empty or Stop() is called.
+*/
+class QueueProcessor final
+{
+public:
+    QueueProcessor (
+        RequestQueue& rQueue,
+        const std::shared_ptr<BitmapCache>& rpCache,
+        const Size& rPreviewSize,
+        const bool bDoSuperSampling,
+        const SharedCacheContext& rpCacheContext);
+    ~QueueProcessor();
+
+    /** Start the processor.  This implementation is timer based and waits
+        a defined amount of time that depends on the given argument before
+        the next entry in the queue is processed.
+        @param nPriorityClass
+            A priority class of 0 tells the processor that a high priority
+            request is waiting in the queue.  The time to wait is thus
+            shorter then that for a low priority request (denoted by a value
+            of 1.)  When the timer is already running it is not modified.
+    */
+    void Start (int nPriorityClass);
+    void Stop();
+    void Pause();
+    void Resume();
+
+    void SetPreviewSize (
+        const Size& rSize,
+        const bool bDoSuperSampling);
+
+    /** Use this method when the page cache is (maybe) using a different
+        BitmapCache.  This is usually necessary after calling
+        PageCacheManager::ChangeSize().
+    */
+    void SetBitmapCache (const std::shared_ptr<BitmapCache>& rpCache);
+
+private:
+    /** This mutex is used to guard the queue processor.  Be careful not to
+        mix its use with that of the solar mutex.
+    */
+    std::mutex maMutex;
+
+    Timer  maTimer;
+    DECL_LINK(ProcessRequestHdl, Timer *, void);
+    Size maPreviewSize;
+    bool mbDoSuperSampling;
+    SharedCacheContext mpCacheContext;
+    RequestQueue& mrQueue;
+    std::shared_ptr<BitmapCache> mpCache;
+    BitmapFactory maBitmapFactory;
+    bool mbIsPaused;
+
+    void ProcessRequests();
+    void ProcessOneRequest (
+        CacheKey aKey,
+        const RequestPriorityClass ePriorityClass);
+};
+
+} // end of namespace ::sd::slidesorter::cache
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/cache/SlsRequestFactory.cxx b/sd/source/ui/slidesorter/cache/SlsRequestFactory.cxx
new file mode 100644
index 000000000..6fc6cabc9
--- /dev/null
+++ b/sd/source/ui/slidesorter/cache/SlsRequestFactory.cxx
@@ -0,0 +1,50 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "SlsRequestFactory.hxx"
+#include "SlsRequestQueue.hxx"
+
+namespace sd::slidesorter::cache {
+
+void RequestFactory::operator()(
+    RequestQueue& rRequestQueue,
+    const SharedCacheContext& rpCacheContext)
+{
+    std::shared_ptr<std::vector<CacheKey> > aKeys;
+
+    // Add the requests for the visible pages.
+    aKeys = rpCacheContext->GetEntryList(true);
+    if (aKeys != nullptr)
+    {
+        for (const auto& rKey : *aKeys)
+            rRequestQueue.AddRequest(rKey, VISIBLE_NO_PREVIEW);
+    }
+
+    // Add the requests for the non-visible pages.
+    aKeys = rpCacheContext->GetEntryList(false);
+    if (aKeys != nullptr)
+    {
+        for (const auto& rKey : *aKeys)
+            rRequestQueue.AddRequest(rKey, NOT_VISIBLE);
+    }
+}
+
+} // end of namespace ::sd::slidesorter::cache
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/cache/SlsRequestFactory.hxx b/sd/source/ui/slidesorter/cache/SlsRequestFactory.hxx
new file mode 100644
index 000000000..3f4207725
--- /dev/null
+++ b/sd/source/ui/slidesorter/cache/SlsRequestFactory.hxx
@@ -0,0 +1,36 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <cache/SlsCacheContext.hxx>
+
+namespace sd::slidesorter::cache
+{
+class RequestQueue;
+
+class RequestFactory
+{
+public:
+    void operator()(RequestQueue& rRequestQueue, const SharedCacheContext& rpCacheContext);
+};
+
+} // end of namespace ::sd::slidesorter::cache
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/cache/SlsRequestPriorityClass.hxx b/sd/source/ui/slidesorter/cache/SlsRequestPriorityClass.hxx
new file mode 100644
index 000000000..2c84ecbcf
--- /dev/null
+++ b/sd/source/ui/slidesorter/cache/SlsRequestPriorityClass.hxx
@@ -0,0 +1,44 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+namespace sd::slidesorter::cache
+{
+/** Each request for a preview creation has a priority.  This enum defines
+    the available priorities.  The special values MIN_CLASS and MAX_CLASS
+    are/can be used for validation and have to be kept up-to-date.
+*/
+enum RequestPriorityClass
+{
+    MIN_CLASS = 0,
+
+    // The slide is visible.  A preview does not yet exist.
+    VISIBLE_NO_PREVIEW = MIN_CLASS,
+    // The slide is visible.  A preview exists but is not up-to-date anymore.
+    VISIBLE_OUTDATED_PREVIEW,
+    // The slide is not visible.
+    NOT_VISIBLE,
+
+    MAX_CLASS = NOT_VISIBLE
+};
+
+} // end of namespace ::sd::slidesorter::cache
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/cache/SlsRequestQueue.cxx b/sd/source/ui/slidesorter/cache/SlsRequestQueue.cxx
new file mode 100644
index 000000000..931c1a8f6
--- /dev/null
+++ b/sd/source/ui/slidesorter/cache/SlsRequestQueue.cxx
@@ -0,0 +1,275 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "SlsRequestQueue.hxx"
+
+#include <sal/log.hxx>
+
+#include <svx/svdpage.hxx>
+
+#include <set>
+
+namespace sd::slidesorter::cache {
+
+namespace {
+
+/** This class extends the actual request data with additional information
+    that is used by the priority queues.
+*/
+class Request
+{
+public:
+    Request (
+        CacheKey aKey, sal_Int32 nPriority, RequestPriorityClass eClass)
+        : maKey(aKey), mnPriorityInClass(nPriority), meClass(eClass)
+    {}
+    /** Sort requests according to priority classes and then to priorities.
+    */
+    class Comparator { public:
+        bool operator() (const Request& rRequest1, const Request& rRequest2)
+            const
+        {
+            if (rRequest1.meClass == rRequest2.meClass)
+            {
+                if (rRequest1.mnPriorityInClass == rRequest2.mnPriorityInClass)
+                {
+                    return rRequest1.maKey < rRequest2.maKey;
+                }
+                return rRequest1.mnPriorityInClass > rRequest2.mnPriorityInClass;
+            }
+            return rRequest1.meClass < rRequest2.meClass;
+        }
+    };
+    /** Request data is compared arbitrarily by their addresses in memory.
+        This just establishes an order so that the STL containers are happy.
+        The order is not semantically interpreted.
+    */
+    class DataComparator
+    {
+    public:
+        explicit DataComparator (const CacheKey aKey)
+            : maKey(aKey)
+        {
+        }
+        bool operator() (const Request& rRequest) const
+        {
+            return maKey == rRequest.maKey;
+        }
+    private:
+        const CacheKey maKey;
+    };
+
+    CacheKey maKey;
+    sal_Int32 mnPriorityInClass;
+    RequestPriorityClass meClass;
+};
+
+}
+
+class RequestQueue::Container
+    : public ::std::set<
+        Request,
+        Request::Comparator>
+{
+};
+
+//=====  GenericRequestQueue  =================================================
+
+RequestQueue::RequestQueue (const SharedCacheContext& rpCacheContext)
+    : mpRequestQueue(new Container),
+      mpCacheContext(rpCacheContext),
+      mnMinimumPriority(0),
+      mnMaximumPriority(1)
+{
+}
+
+RequestQueue::~RequestQueue()
+{
+    Clear();
+}
+
+void RequestQueue::AddRequest (
+    CacheKey aKey,
+    RequestPriorityClass eRequestClass)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    assert(eRequestClass>=MIN_CLASS && eRequestClass<=MAX_CLASS);
+
+    // If the request is already a member of the queue then remove it so
+    // that the following insertion will use the new prioritization.
+#if OSL_DEBUG_LEVEL >=2
+    bool bRemoved =
+#endif
+    RemoveRequest(aKey);
+
+    // The priority of the request inside its priority class is defined by
+    // the page number.  This ensures a strict top-to-bottom, left-to-right
+    // order.
+    sal_Int32 nPriority (mpCacheContext->GetPriority(aKey));
+    Request aRequest (aKey, nPriority, eRequestClass);
+
+    std::pair<Container::iterator,bool> ret = mpRequestQueue->insert(aRequest);
+    bool bInserted = ret.second;
+
+    if (bInserted)
+    {
+        SdrPage *pPage = const_cast<SdrPage*>(aRequest.maKey);
+        pPage->AddPageUser(*this);
+    }
+
+#if OSL_DEBUG_LEVEL >=2
+    SAL_INFO("sd.sls", __func__ << ": " << (bRemoved?"replaced":"added")
+        << " request for page " << ((aKey->GetPageNum()-1)/2)
+        << " with priority class " << static_cast<int>(eRequestClass));
+#endif
+}
+
+void RequestQueue::PageInDestruction(const SdrPage& rPage)
+{
+    //remove any requests pending for this page which is going away now
+    RemoveRequest(&rPage);
+}
+
+#if OSL_DEBUG_LEVEL >=2
+bool
+#else
+void
+#endif
+RequestQueue::RemoveRequest(
+    CacheKey aKey)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+#if OSL_DEBUG_LEVEL >=2
+    bool bIsRemoved = false;
+#endif
+    while(true)
+    {
+        Container::const_iterator aRequestIterator = ::std::find_if (
+            mpRequestQueue->begin(),
+            mpRequestQueue->end(),
+            Request::DataComparator(aKey));
+        if (aRequestIterator != mpRequestQueue->end())
+        {
+            if (aRequestIterator->mnPriorityInClass == mnMinimumPriority+1)
+                mnMinimumPriority++;
+            else if (aRequestIterator->mnPriorityInClass == mnMaximumPriority-1)
+                mnMaximumPriority--;
+
+            SdrPage *pPage = const_cast<SdrPage*>(aRequestIterator->maKey);
+            pPage->RemovePageUser(*this);
+            mpRequestQueue->erase(aRequestIterator);
+#if OSL_DEBUG_LEVEL >=2
+            bIsRemoved = true;
+#endif
+        }
+        else
+            break;
+    }
+#if OSL_DEBUG_LEVEL >=2
+    return bIsRemoved;
+#endif
+
+}
+
+void RequestQueue::ChangeClass (
+    CacheKey aKey,
+    RequestPriorityClass eNewRequestClass)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    assert(eNewRequestClass>=MIN_CLASS && eNewRequestClass<=MAX_CLASS);
+
+    Container::const_iterator iRequest (
+        ::std::find_if (
+            mpRequestQueue->begin(),
+            mpRequestQueue->end(),
+            Request::DataComparator(aKey)));
+    if (iRequest!=mpRequestQueue->end() && iRequest->meClass!=eNewRequestClass)
+    {
+        AddRequest(aKey, eNewRequestClass);
+    }
+}
+
+CacheKey RequestQueue::GetFront()
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    if (mpRequestQueue->empty())
+        throw css::uno::RuntimeException("RequestQueue::GetFront(): queue is empty",
+            nullptr);
+
+    return mpRequestQueue->begin()->maKey;
+}
+
+RequestPriorityClass RequestQueue::GetFrontPriorityClass()
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    if (mpRequestQueue->empty())
+        throw css::uno::RuntimeException("RequestQueue::GetFrontPriorityClass(): queue is empty",
+            nullptr);
+
+    return mpRequestQueue->begin()->meClass;
+}
+
+void RequestQueue::PopFront()
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    if (  mpRequestQueue->empty())
+        return;
+
+    Container::const_iterator aIter(mpRequestQueue->begin());
+    SdrPage *pPage = const_cast<SdrPage*>(aIter->maKey);
+    pPage->RemovePageUser(*this);
+    mpRequestQueue->erase(aIter);
+
+    // Reset the priority counter if possible.
+    if (mpRequestQueue->empty())
+    {
+        mnMinimumPriority = 0;
+        mnMaximumPriority = 1;
+    }
+}
+
+bool RequestQueue::IsEmpty()
+{
+    ::osl::MutexGuard aGuard (maMutex);
+    return mpRequestQueue->empty();
+}
+
+void RequestQueue::Clear()
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    for (const auto& rItem : *mpRequestQueue)
+    {
+        SdrPage *pPage = const_cast<SdrPage*>(rItem.maKey);
+        pPage->RemovePageUser(*this);
+    }
+
+    mpRequestQueue->clear();
+    mnMinimumPriority = 0;
+    mnMaximumPriority = 1;
+}
+
+} // end of namespace ::sd::slidesorter::cache
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/cache/SlsRequestQueue.hxx b/sd/source/ui/slidesorter/cache/SlsRequestQueue.hxx
new file mode 100644
index 000000000..618ba5801
--- /dev/null
+++ b/sd/source/ui/slidesorter/cache/SlsRequestQueue.hxx
@@ -0,0 +1,122 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include "SlsRequestPriorityClass.hxx"
+#include <cache/SlsCacheContext.hxx>
+#include <osl/mutex.hxx>
+#include <svx/sdrpageuser.hxx>
+
+#include <memory>
+
+namespace sd::slidesorter::cache
+{
+/** The request queue stores requests that are described by the Request
+    sorted according to priority class and then priority.
+*/
+class RequestQueue : public sdr::PageUser
+{
+public:
+    explicit RequestQueue(const SharedCacheContext& rpCacheContext);
+    virtual ~RequestQueue();
+
+    /** Insert a request with highest or lowest priority in its priority
+        class.  When the request is already present then it is first
+        removed.  This effect is then a re-prioritization.
+        @param aKey
+            The request.
+        @param eRequestClass
+            The priority class in which to insert the request with highest
+            or lowest priority.
+        @param bInsertWithHighestPriority
+            When this flag is <TRUE/> the request is inserted with highest
+            priority in its class.  When <FALSE/> the request is inserted
+            with lowest priority.
+    */
+    void AddRequest(CacheKey aKey, RequestPriorityClass eRequestClass);
+
+    /** Remove the specified request from the queue.
+        @param aKey
+            It is OK when the specified request is not a member of the
+            queue.
+    */
+#if OSL_DEBUG_LEVEL >= 2
+    bool
+#else
+    void
+#endif
+    RemoveRequest(CacheKey aKey);
+
+    /** Change the priority class of the specified request.
+    */
+    void ChangeClass(CacheKey aKey, RequestPriorityClass eNewRequestClass);
+
+    /** Get the request with the highest priority int the highest priority class.
+    */
+    CacheKey GetFront();
+
+    // For debugging.
+    RequestPriorityClass GetFrontPriorityClass();
+
+    /** Really a synonym for RemoveRequest(GetFront());
+    */
+    void PopFront();
+
+    /** Returns <TRUE/> when there is no element in the queue.
+    */
+    bool IsEmpty();
+
+    /** Remove all requests from the queue.  This resets the minimum and
+        maximum priorities to their default values.
+    */
+    void Clear();
+
+    /** Return the mutex that guards the access to the priority queue.
+    */
+    ::osl::Mutex& GetMutex() { return maMutex; }
+
+    /** Ensure we don't hand out a page deleted before anyone got a
+        chance to process it
+    */
+    virtual void PageInDestruction(const SdrPage& rPage) override;
+
+private:
+    ::osl::Mutex maMutex;
+    class Container;
+    std::unique_ptr<Container> mpRequestQueue;
+    SharedCacheContext mpCacheContext;
+
+    /** A lower bound of the lowest priority of all elements in the queues.
+        The start value is 0.  It is assigned and then decreased every time
+        when an element is inserted or marked as the request with lowest
+        priority.
+    */
+    int mnMinimumPriority;
+    /** An upper bound of the highest priority of all elements in the queues.
+        The start value is 1.  It is assigned and then increased every time
+        when an element is inserted or marked as the request with highest
+        priority.
+    */
+    int mnMaximumPriority;
+};
+
+} // end of namespace ::sd::slidesorter::cache
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/controller/SlideSorterController.cxx b/sd/source/ui/slidesorter/controller/SlideSorterController.cxx
new file mode 100644
index 000000000..5c851f183
--- /dev/null
+++ b/sd/source/ui/slidesorter/controller/SlideSorterController.cxx
@@ -0,0 +1,910 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <controller/SlideSorterController.hxx>
+
+#include <SlideSorter.hxx>
+#include <controller/SlsPageSelector.hxx>
+#include <controller/SlsSelectionFunction.hxx>
+#include <controller/SlsProperties.hxx>
+#include <controller/SlsCurrentSlideManager.hxx>
+#include "SlsListener.hxx"
+#include <controller/SlsFocusManager.hxx>
+#include <controller/SlsAnimator.hxx>
+#include <controller/SlsClipboard.hxx>
+#include <controller/SlsInsertionIndicatorHandler.hxx>
+#include <controller/SlsScrollBarManager.hxx>
+#include <controller/SlsSelectionManager.hxx>
+#include <controller/SlsSlotManager.hxx>
+#include <controller/SlsVisibleAreaManager.hxx>
+#include <model/SlideSorterModel.hxx>
+#include <model/SlsPageEnumerationProvider.hxx>
+#include <model/SlsPageDescriptor.hxx>
+#include <view/SlideSorterView.hxx>
+#include <view/SlsLayouter.hxx>
+#include <view/SlsPageObjectLayouter.hxx>
+#include <view/SlsTheme.hxx>
+#include <view/SlsToolTip.hxx>
+#include <cache/SlsPageCache.hxx>
+#include <cache/SlsPageCacheManager.hxx>
+#include <tools/diagnose_ex.h>
+
+#include <drawdoc.hxx>
+#include <ViewShellBase.hxx>
+#include <Window.hxx>
+#include <FrameView.hxx>
+#include <sdpage.hxx>
+
+#include <app.hrc>
+#include <sdmod.hxx>
+#include <ViewShellHint.hxx>
+#include <AccessibleSlideSorterView.hxx>
+#include <AccessibleSlideSorterObject.hxx>
+
+#include <vcl/window.hxx>
+#include <svx/svxids.hrc>
+#include <sfx2/request.hxx>
+#include <sfx2/viewfrm.hxx>
+#include <sfx2/dispatch.hxx>
+#include <tools/debug.hxx>
+#include <vcl/commandevent.hxx>
+#include <vcl/svapp.hxx>
+#include <vcl/settings.hxx>
+
+#include <com/sun/star/lang/XComponent.hpp>
+#include <com/sun/star/accessibility/AccessibleEventId.hpp>
+
+#include <memory>
+
+using namespace ::com::sun::star;
+using namespace ::com::sun::star::uno;
+using namespace ::sd::slidesorter::model;
+using namespace ::sd::slidesorter::view;
+using namespace ::sd::slidesorter::controller;
+using namespace ::basegfx;
+
+namespace sd::slidesorter::controller {
+
+SlideSorterController::SlideSorterController (SlideSorter& rSlideSorter)
+    : mrSlideSorter(rSlideSorter),
+      mrModel(mrSlideSorter.GetModel()),
+      mrView(mrSlideSorter.GetView()),
+      mpInsertionIndicatorHandler(std::make_shared<InsertionIndicatorHandler>(rSlideSorter)),
+      mpAnimator(std::make_shared<Animator>(rSlideSorter)),
+      mpVisibleAreaManager(new VisibleAreaManager(rSlideSorter)),
+      mnModelChangeLockCount(0),
+      mbIsForcedRearrangePending(false),
+      mbContextMenuOpen(false),
+      mbPostModelChangePending(false),
+      mnCurrentPageBeforeSwitch(0),
+      mpEditModeChangeMasterPage(nullptr),
+      mnPaintEntranceCount(0)
+{
+    sd::Window *pWindow (mrSlideSorter.GetContentWindow().get());
+    OSL_ASSERT(pWindow);
+    if (!pWindow)
+        return;
+
+    // The whole background is painted by the view and controls.
+    vcl::Window* pParentWindow = pWindow->GetParent();
+    OSL_ASSERT(pParentWindow!=nullptr);
+    pParentWindow->SetBackground (Wallpaper());
+
+    // Connect the view with the window that has been created by our base
+    // class.
+    pWindow->SetBackground(Wallpaper());
+    pWindow->SetCenterAllowed(false);
+    pWindow->SetMapMode(MapMode(MapUnit::MapPixel));
+    pWindow->SetViewSize(mrView.GetModelArea().GetSize());
+}
+
+void SlideSorterController::Init()
+{
+    mpCurrentSlideManager = std::make_shared<CurrentSlideManager>(mrSlideSorter);
+    mpPageSelector.reset(new PageSelector(mrSlideSorter));
+    mpFocusManager.reset(new FocusManager(mrSlideSorter));
+    mpSlotManager = std::make_shared<SlotManager>(mrSlideSorter);
+    mpScrollBarManager.reset(new ScrollBarManager(mrSlideSorter));
+    mpSelectionManager = std::make_shared<SelectionManager>(mrSlideSorter);
+    mpClipboard.reset(new Clipboard(mrSlideSorter));
+
+    // Create the selection function.
+    SfxRequest aRequest (
+        SID_OBJECT_SELECT,
+        SfxCallMode::SLOT,
+        mrModel.GetDocument()->GetItemPool());
+    mrSlideSorter.SetCurrentFunction(CreateSelectionFunction(aRequest));
+
+    mpListener = new Listener(mrSlideSorter);
+
+    mpPageSelector->GetCoreSelection();
+    GetSelectionManager()->SelectionHasChanged();
+}
+
+SlideSorterController::~SlideSorterController()
+{
+    try
+    {
+        uno::Reference<lang::XComponent> xComponent = mpListener;
+        if (xComponent.is())
+            xComponent->dispose();
+    }
+    catch( uno::Exception& )
+    {
+        TOOLS_WARN_EXCEPTION( "sd", "sd::SlideSorterController::~SlideSorterController()" );
+    }
+
+    // dispose should have been called by now so that nothing is to be done
+    // to shut down cleanly.
+}
+
+void SlideSorterController::Dispose()
+{
+    mpInsertionIndicatorHandler->End(Animator::AM_Immediate);
+    mpClipboard.reset();
+    mpSelectionManager.reset();
+    mpAnimator->Dispose();
+}
+
+model::SharedPageDescriptor SlideSorterController::GetPageAt (
+    const Point& aWindowPosition)
+{
+    sal_Int32 nHitPageIndex (mrView.GetPageIndexAtPoint(aWindowPosition));
+    model::SharedPageDescriptor pDescriptorAtPoint;
+    if (nHitPageIndex >= 0)
+    {
+        pDescriptorAtPoint = mrModel.GetPageDescriptor(nHitPageIndex);
+
+        // Depending on a property we may have to check that the mouse is no
+        // just over the page object but over the preview area.
+        if (pDescriptorAtPoint
+            && ! pDescriptorAtPoint->HasState(PageDescriptor::ST_Selected))
+        {
+            // Make sure that the mouse is over the preview area.
+            if ( ! mrView.GetLayouter().GetPageObjectLayouter()->GetBoundingBox(
+                pDescriptorAtPoint,
+                view::PageObjectLayouter::Part::Preview,
+                view::PageObjectLayouter::WindowCoordinateSystem).Contains(aWindowPosition))
+            {
+                pDescriptorAtPoint.reset();
+            }
+        }
+    }
+
+    return pDescriptorAtPoint;
+}
+
+PageSelector& SlideSorterController::GetPageSelector()
+{
+    OSL_ASSERT(mpPageSelector != nullptr);
+    return *mpPageSelector;
+}
+
+FocusManager& SlideSorterController::GetFocusManager()
+{
+    OSL_ASSERT(mpFocusManager != nullptr);
+    return *mpFocusManager;
+}
+
+Clipboard& SlideSorterController::GetClipboard()
+{
+    OSL_ASSERT(mpClipboard != nullptr);
+    return *mpClipboard;
+}
+
+ScrollBarManager& SlideSorterController::GetScrollBarManager()
+{
+    OSL_ASSERT(mpScrollBarManager != nullptr);
+    return *mpScrollBarManager;
+}
+
+std::shared_ptr<CurrentSlideManager> const & SlideSorterController::GetCurrentSlideManager() const
+{
+    OSL_ASSERT(mpCurrentSlideManager != nullptr);
+    return mpCurrentSlideManager;
+}
+
+std::shared_ptr<SlotManager> const & SlideSorterController::GetSlotManager() const
+{
+    OSL_ASSERT(mpSlotManager != nullptr);
+    return mpSlotManager;
+}
+
+std::shared_ptr<SelectionManager> const & SlideSorterController::GetSelectionManager() const
+{
+    OSL_ASSERT(mpSelectionManager != nullptr);
+    return mpSelectionManager;
+}
+
+std::shared_ptr<InsertionIndicatorHandler> const &
+    SlideSorterController::GetInsertionIndicatorHandler() const
+{
+    OSL_ASSERT(mpInsertionIndicatorHandler != nullptr);
+    return mpInsertionIndicatorHandler;
+}
+
+void SlideSorterController::Paint (
+    const ::tools::Rectangle& rBBox,
+    vcl::Window* pWindow)
+{
+    if (mnPaintEntranceCount != 0)
+        return;
+
+    ++mnPaintEntranceCount;
+
+    try
+    {
+        mrView.CompleteRedraw(pWindow->GetOutDev(), vcl::Region(rBBox));
+    }
+    catch (const Exception&)
+    {
+        // Ignore all exceptions.
+    }
+
+    --mnPaintEntranceCount;
+}
+
+void SlideSorterController::FuTemporary (SfxRequest& rRequest)
+{
+    mpSlotManager->FuTemporary (rRequest);
+}
+
+void SlideSorterController::FuPermanent (SfxRequest &rRequest)
+{
+    mpSlotManager->FuPermanent (rRequest);
+}
+
+void SlideSorterController::FuSupport (SfxRequest &rRequest)
+{
+    mpSlotManager->FuSupport (rRequest);
+}
+
+bool SlideSorterController::Command (
+    const CommandEvent& rEvent,
+    ::sd::Window* pWindow)
+{
+    bool bEventHasBeenHandled = false;
+
+    if (pWindow == nullptr)
+        return false;
+
+    ViewShell* pViewShell = mrSlideSorter.GetViewShell();
+    if (pViewShell == nullptr)
+        return false;
+
+    switch (rEvent.GetCommand())
+    {
+        case CommandEventId::ContextMenu:
+        {
+            SdPage* pPage = nullptr;
+            OUString aPopupId;
+
+            model::PageEnumeration aSelectedPages (
+                PageEnumerationProvider::CreateSelectedPagesEnumeration(mrModel));
+            if (aSelectedPages.HasMoreElements())
+                pPage = aSelectedPages.GetNextElement()->GetPage();
+
+            if (mrModel.GetEditMode() == EditMode::Page)
+            {
+                if (pPage != nullptr)
+                    aPopupId = "pagepane";
+                else
+                    aPopupId = "pagepanenosel";
+            }
+            else if (pPage != nullptr)
+                aPopupId = "pagepanemaster";
+            else
+                aPopupId = "pagepanenoselmaster";
+
+            std::unique_ptr<InsertionIndicatorHandler::ForceShowContext, o3tl::default_delete<InsertionIndicatorHandler::ForceShowContext>> xContext;
+            if (pPage == nullptr)
+            {
+                // When there is no selection, then we show the insertion
+                // indicator so that the user knows where a page insertion
+                // would take place.
+                mpInsertionIndicatorHandler->Start(false);
+                mpInsertionIndicatorHandler->UpdateIndicatorIcon(SD_MOD()->pTransferClip);
+                mpInsertionIndicatorHandler->UpdatePosition(
+                    pWindow->PixelToLogic(rEvent.GetMousePosPixel()),
+                    InsertionIndicatorHandler::MoveMode);
+                xContext.reset(new InsertionIndicatorHandler::ForceShowContext(
+                    mpInsertionIndicatorHandler));
+            }
+
+            pWindow->ReleaseMouse();
+
+            Point aMenuLocation (0,0);
+            if (!rEvent.IsMouseEvent())
+            {
+                // The event is not a mouse event.  Use the center of the
+                // focused page as top left position of the context menu.
+                model::SharedPageDescriptor pDescriptor (
+                    GetFocusManager().GetFocusedPageDescriptor());
+                if (pDescriptor)
+                {
+                    ::tools::Rectangle aBBox (
+                        mrView.GetLayouter().GetPageObjectLayouter()->GetBoundingBox (
+                            pDescriptor,
+                            PageObjectLayouter::Part::PageObject,
+                            PageObjectLayouter::ModelCoordinateSystem));
+                    aMenuLocation = aBBox.Center();
+                }
+            }
+
+            if (SfxDispatcher* pDispatcher = pViewShell->GetDispatcher())
+            {
+                mbContextMenuOpen = true;
+                if (!rEvent.IsMouseEvent())
+                    pDispatcher->ExecutePopup(aPopupId, pWindow, &aMenuLocation);
+                else
+                    pDispatcher->ExecutePopup(aPopupId, pWindow);
+                mbContextMenuOpen = false;
+                mrSlideSorter.GetView().UpdatePageUnderMouse();
+                ::rtl::Reference<SelectionFunction> pFunction(GetCurrentSelectionFunction());
+                if (pFunction.is())
+                    pFunction->ResetMouseAnchor();
+            }
+            if (pPage == nullptr)
+            {
+                // Remember the position of the insertion indicator before
+                // it is hidden, so that a pending slide insertion slot call
+                // finds the right place to insert a new slide.
+                GetSelectionManager()->SetInsertionPosition(
+                    GetInsertionIndicatorHandler()->GetInsertionPageIndex());
+            }
+            xContext.reset();
+            bEventHasBeenHandled = true;
+        }
+        break;
+
+        case CommandEventId::Wheel:
+        {
+            const CommandWheelData* pData = rEvent.GetWheelData();
+            if (pData == nullptr)
+                return false;
+            if (pData->IsMod1())
+            {
+                // We do not support zooming with control+mouse wheel.
+                return false;
+            }
+            // Determine whether to scroll horizontally or vertically.  This
+            // depends on the orientation of the scroll bar and the
+            // IsHoriz() flag of the event.
+            if ((mrSlideSorter.GetView().GetOrientation()==view::Layouter::HORIZONTAL)
+                == pData->IsHorz())
+            {
+                GetScrollBarManager().Scroll(
+                    ScrollBarManager::Orientation_Vertical,
+                    -pData->GetNotchDelta());
+            }
+            else
+            {
+                GetScrollBarManager().Scroll(
+                    ScrollBarManager::Orientation_Horizontal,
+                    -pData->GetNotchDelta());
+            }
+            mrSlideSorter.GetView().UpdatePageUnderMouse(rEvent.GetMousePosPixel());
+
+            bEventHasBeenHandled = true;
+        }
+        break;
+
+        default: break;
+    }
+
+    return bEventHasBeenHandled;
+}
+
+void SlideSorterController::LockModelChange()
+{
+    mnModelChangeLockCount += 1;
+}
+
+void SlideSorterController::UnlockModelChange()
+{
+    mnModelChangeLockCount -= 1;
+    if (mnModelChangeLockCount==0 && mbPostModelChangePending)
+    {
+        PostModelChange();
+    }
+}
+
+void SlideSorterController::PreModelChange()
+{
+    // Prevent PreModelChange to execute more than once per model lock.
+    if (mbPostModelChangePending)
+        return;
+
+    if (mrSlideSorter.GetViewShell() != nullptr)
+        mrSlideSorter.GetViewShell()->Broadcast(
+            ViewShellHint(ViewShellHint::HINT_COMPLEX_MODEL_CHANGE_START));
+
+    GetCurrentSlideManager()->PrepareModelChange();
+
+    if (mrSlideSorter.GetContentWindow())
+        mrView.PreModelChange();
+
+    mbPostModelChangePending = true;
+}
+
+void SlideSorterController::PostModelChange()
+{
+    mbPostModelChangePending = false;
+    mrModel.Resync();
+
+    sd::Window *pWindow (mrSlideSorter.GetContentWindow().get());
+    if (pWindow)
+    {
+        GetCurrentSlideManager()->HandleModelChange();
+
+        mrView.PostModelChange ();
+
+        pWindow->SetViewOrigin (Point (0,0));
+        pWindow->SetViewSize (mrView.GetModelArea().GetSize());
+
+        // The visibility of the scroll bars may have to be changed.  Then
+        // the size of the view has to change, too.  Let Rearrange() handle
+        // that.
+        Rearrange(mbIsForcedRearrangePending);
+    }
+
+    if (mrSlideSorter.GetViewShell() != nullptr)
+        mrSlideSorter.GetViewShell()->Broadcast(
+            ViewShellHint(ViewShellHint::HINT_COMPLEX_MODEL_CHANGE_END));
+}
+
+void SlideSorterController::HandleModelChange()
+{
+    // Ignore this call when the document is not in a valid state, i.e. has
+    // not the same number of regular and notes pages.
+    bool bIsDocumentValid = (mrModel.GetDocument()->GetPageCount() % 2 == 1);
+
+    if (bIsDocumentValid)
+    {
+        ModelChangeLock aLock (*this);
+        PreModelChange();
+    }
+}
+
+IMPL_LINK(SlideSorterController, ApplicationEventHandler, VclSimpleEvent&, rEvent, void)
+{
+    auto windowEvent = dynamic_cast<VclWindowEvent *>(&rEvent);
+    if (windowEvent != nullptr) {
+        WindowEventHandler(*windowEvent);
+    }
+}
+IMPL_LINK(SlideSorterController, WindowEventHandler, VclWindowEvent&, rEvent, void)
+{
+        vcl::Window* pWindow = rEvent.GetWindow();
+        sd::Window *pActiveWindow (mrSlideSorter.GetContentWindow().get());
+        switch (rEvent.GetId())
+        {
+            case VclEventId::WindowActivate:
+            case VclEventId::WindowShow:
+                if (pActiveWindow && pWindow == pActiveWindow->GetParent())
+                    mrView.RequestRepaint();
+                break;
+
+            case VclEventId::WindowHide:
+                if (pActiveWindow && pWindow == pActiveWindow->GetParent())
+                    mrView.SetPageUnderMouse(SharedPageDescriptor());
+                break;
+
+            case VclEventId::WindowGetFocus:
+                if (pActiveWindow)
+                    if (pWindow == pActiveWindow)
+                        GetFocusManager().ShowFocus(false);
+                break;
+
+            case VclEventId::WindowLoseFocus:
+                if (pActiveWindow && pWindow == pActiveWindow)
+                {
+                    GetFocusManager().HideFocus();
+                    mrView.GetToolTip().Hide();
+
+                    //don't scroll back to the selected slide when we lose
+                    //focus due to a temporary active context menu
+                    if (!mbContextMenuOpen)
+                    {
+                        // Select the current slide so that it is properly
+                        // visualized when the focus is moved to the edit view.
+                        GetPageSelector().SelectPage(GetCurrentSlideManager()->GetCurrentSlide());
+                    }
+                }
+                break;
+
+            case VclEventId::ApplicationDataChanged:
+            {
+                // Invalidate the preview cache.
+                cache::PageCacheManager::Instance()->InvalidateAllCaches();
+
+                // Update the draw mode.
+                DrawModeFlags nDrawMode (Application::GetSettings().GetStyleSettings().GetHighContrastMode()
+                    ? sd::OUTPUT_DRAWMODE_CONTRAST
+                    : sd::OUTPUT_DRAWMODE_COLOR);
+                if (mrSlideSorter.GetViewShell() != nullptr)
+                    mrSlideSorter.GetViewShell()->GetFrameView()->SetDrawMode(nDrawMode);
+                if (pActiveWindow != nullptr)
+                    pActiveWindow->GetOutDev()->SetDrawMode(nDrawMode);
+                mrView.HandleDrawModeChange();
+
+                // When the system font has changed a layout has to be done.
+                mrView.Resize();
+
+                // Update theme colors.
+                mrSlideSorter.GetProperties()->HandleDataChangeEvent();
+                mrSlideSorter.GetTheme()->Update(mrSlideSorter.GetProperties());
+                mrView.HandleDataChangeEvent();
+            }
+            break;
+
+            default:
+                break;
+        }
+}
+
+void SlideSorterController::GetCtrlState (SfxItemSet& rSet)
+{
+    if (rSet.GetItemState(SID_RELOAD) != SfxItemState::UNKNOWN)
+    {
+        // let SFx en-/disable "last version"
+        SfxViewFrame* pSlideViewFrame = SfxViewFrame::Current();
+        DBG_ASSERT(pSlideViewFrame!=nullptr,
+            "SlideSorterController::GetCtrlState: ViewFrame not found");
+        if (pSlideViewFrame)
+        {
+            pSlideViewFrame->GetSlotState (SID_RELOAD, nullptr, &rSet);
+        }
+        else        // MI says: no MDIFrame --> disable
+        {
+            rSet.DisableItem(SID_RELOAD);
+        }
+    }
+
+    // Output quality.
+    if (rSet.GetItemState(SID_OUTPUT_QUALITY_COLOR)==SfxItemState::DEFAULT
+        ||rSet.GetItemState(SID_OUTPUT_QUALITY_GRAYSCALE)==SfxItemState::DEFAULT
+        ||rSet.GetItemState(SID_OUTPUT_QUALITY_BLACKWHITE)==SfxItemState::DEFAULT
+        ||rSet.GetItemState(SID_OUTPUT_QUALITY_CONTRAST)==SfxItemState::DEFAULT)
+    {
+        if (mrSlideSorter.GetContentWindow())
+        {
+            DrawModeFlags nMode = mrSlideSorter.GetContentWindow()->GetOutDev()->GetDrawMode();
+            sal_uInt16 nQuality = 0;
+
+            if (nMode == sd::OUTPUT_DRAWMODE_COLOR) {
+                nQuality = 0;
+            } else if (nMode == sd::OUTPUT_DRAWMODE_GRAYSCALE) {
+                nQuality = 1;
+            } else if (nMode == sd::OUTPUT_DRAWMODE_BLACKWHITE) {
+                nQuality = 2;
+            } else if (nMode == sd::OUTPUT_DRAWMODE_CONTRAST) {
+                nQuality = 3;
+            }
+
+            rSet.Put (SfxBoolItem (SID_OUTPUT_QUALITY_COLOR, nQuality==0));
+            rSet.Put (SfxBoolItem (SID_OUTPUT_QUALITY_GRAYSCALE, nQuality==1));
+            rSet.Put (SfxBoolItem (SID_OUTPUT_QUALITY_BLACKWHITE, nQuality==2));
+            rSet.Put (SfxBoolItem (SID_OUTPUT_QUALITY_CONTRAST, nQuality==3));
+        }
+    }
+
+    if (rSet.GetItemState(SID_MAIL_SCROLLBODY_PAGEDOWN) == SfxItemState::DEFAULT)
+    {
+        rSet.Put (SfxBoolItem( SID_MAIL_SCROLLBODY_PAGEDOWN, true));
+    }
+}
+
+void SlideSorterController::GetStatusBarState (SfxItemSet& rSet)
+{
+    mpSlotManager->GetStatusBarState (rSet);
+}
+
+void SlideSorterController::ExecCtrl (SfxRequest& rRequest)
+{
+    mpSlotManager->ExecCtrl (rRequest);
+}
+
+void SlideSorterController::GetAttrState (SfxItemSet& rSet)
+{
+    mpSlotManager->GetAttrState (rSet);
+}
+
+void SlideSorterController::UpdateAllPages()
+{
+    // Do a redraw.
+    mrSlideSorter.GetContentWindow()->Invalidate();
+}
+
+void SlideSorterController::Resize (const ::tools::Rectangle& rAvailableSpace)
+{
+    if (maTotalWindowArea != rAvailableSpace)
+    {
+        maTotalWindowArea = rAvailableSpace;
+        Rearrange(true);
+    }
+}
+
+void  SlideSorterController::Rearrange (bool bForce)
+{
+    if (maTotalWindowArea.IsEmpty())
+        return;
+
+    if (mnModelChangeLockCount>0)
+    {
+        mbIsForcedRearrangePending |= bForce;
+        return;
+    }
+    else
+        mbIsForcedRearrangePending = false;
+
+    sd::Window *pWindow (mrSlideSorter.GetContentWindow().get());
+    if (!pWindow)
+        return;
+
+    if (bForce)
+        mrView.UpdateOrientation();
+
+    // Place the scroll bars.
+    ::tools::Rectangle aNewContentArea = GetScrollBarManager().PlaceScrollBars(
+        maTotalWindowArea,
+        mrView.GetOrientation() != view::Layouter::VERTICAL,
+        mrView.GetOrientation() != view::Layouter::HORIZONTAL);
+
+    bool bSizeHasChanged (false);
+    // Only when bForce is not true we have to test for a size change in
+    // order to determine whether the window and the view have to be resized.
+    if ( ! bForce)
+    {
+        ::tools::Rectangle aCurrentContentArea (pWindow->GetPosPixel(), pWindow->GetOutputSizePixel());
+        bSizeHasChanged = (aNewContentArea != aCurrentContentArea);
+    }
+    if (bForce || bSizeHasChanged)
+    {
+        // The browser window gets the remaining space.
+        pWindow->SetPosSizePixel (aNewContentArea.TopLeft(), aNewContentArea.GetSize());
+        mrView.Resize();
+    }
+
+    // Adapt the scroll bars to the new zoom factor of the browser
+    // window and the arrangement of the page objects.
+    GetScrollBarManager().UpdateScrollBars(!bForce);
+
+    // Keep the current slide in the visible area.
+    GetVisibleAreaManager().RequestCurrentSlideVisible();
+
+    mrView.RequestRepaint();
+}
+
+rtl::Reference<FuPoor> SlideSorterController::CreateSelectionFunction (SfxRequest& rRequest)
+{
+    rtl::Reference<FuPoor> xFunc( SelectionFunction::Create(mrSlideSorter, rRequest) );
+    return xFunc;
+}
+
+::rtl::Reference<SelectionFunction> SlideSorterController::GetCurrentSelectionFunction() const
+{
+    rtl::Reference<FuPoor> pFunction (mrSlideSorter.GetViewShell()->GetCurrentFunction());
+    return ::rtl::Reference<SelectionFunction>(dynamic_cast<SelectionFunction*>(pFunction.get()));
+}
+
+void SlideSorterController::PrepareEditModeChange()
+{
+    //  Before we throw away the page descriptors we prepare for selecting
+    //  descriptors in the other mode and for restoring the current
+    //  selection when switching back to the current mode.
+    if (mrModel.GetEditMode() != EditMode::Page)
+        return;
+
+    maSelectionBeforeSwitch.clear();
+
+    // Search for the first selected page and determine the master page
+    // used by its page object.  It will be selected after the switch.
+    // In the same loop the current selection is stored.
+    PageEnumeration aSelectedPages (
+        PageEnumerationProvider::CreateSelectedPagesEnumeration(mrModel));
+    while (aSelectedPages.HasMoreElements())
+    {
+        SharedPageDescriptor pDescriptor (aSelectedPages.GetNextElement());
+        SdPage* pPage = pDescriptor->GetPage();
+        // Remember the master page of the first selected descriptor.
+        if (pPage!=nullptr && mpEditModeChangeMasterPage==nullptr)
+            mpEditModeChangeMasterPage = &static_cast<SdPage&>(
+                pPage->TRG_GetMasterPage());
+
+        maSelectionBeforeSwitch.push_back(pPage);
+    }
+
+    // Remember the current page.
+    if (mrSlideSorter.GetViewShell() != nullptr)
+        mnCurrentPageBeforeSwitch = (mrSlideSorter.GetViewShell()->GetViewShellBase()
+        .GetMainViewShell()->GetActualPage()->GetPageNum()-1)/2;
+}
+
+void SlideSorterController::ChangeEditMode (EditMode eEditMode)
+{
+    if (mrModel.GetEditMode() != eEditMode)
+    {
+        ModelChangeLock aLock (*this);
+        PreModelChange();
+        // Do the actual edit mode switching.
+        bool bResult = mrModel.SetEditMode(eEditMode);
+        if (bResult)
+            HandleModelChange();
+    }
+}
+
+void SlideSorterController::FinishEditModeChange()
+{
+    if (mrModel.GetEditMode() == EditMode::MasterPage)
+    {
+        mpPageSelector->DeselectAllPages();
+
+        // Search for the master page that was determined in
+        // PrepareEditModeChange() and make it the current page.
+        PageEnumeration aAllPages (PageEnumerationProvider::CreateAllPagesEnumeration(mrModel));
+        while (aAllPages.HasMoreElements())
+        {
+            SharedPageDescriptor pDescriptor (aAllPages.GetNextElement());
+            if (pDescriptor->GetPage() == mpEditModeChangeMasterPage)
+            {
+                GetCurrentSlideManager()->SwitchCurrentSlide(pDescriptor);
+                mpPageSelector->SelectPage(pDescriptor);
+                break;
+            }
+        }
+    }
+    else
+    {
+        PageSelector::BroadcastLock aBroadcastLock (*mpPageSelector);
+
+        SharedPageDescriptor pDescriptor (mrModel.GetPageDescriptor(mnCurrentPageBeforeSwitch));
+        GetCurrentSlideManager()->SwitchCurrentSlide(pDescriptor);
+
+        // Restore the selection.
+        mpPageSelector->DeselectAllPages();
+        for (const auto& rpPage : maSelectionBeforeSwitch)
+        {
+            mpPageSelector->SelectPage(rpPage);
+        }
+        maSelectionBeforeSwitch.clear( );
+    }
+    mpEditModeChangeMasterPage = nullptr;
+}
+
+void SlideSorterController::PageNameHasChanged (int nPageIndex, const OUString& rsOldName)
+{
+    // Request a repaint for the page object whose name has changed.
+    model::SharedPageDescriptor pDescriptor (mrModel.GetPageDescriptor(nPageIndex));
+    if (pDescriptor)
+        mrView.RequestRepaint(pDescriptor);
+
+    // Get a pointer to the corresponding accessible object and notify
+    // that of the name change.
+    sd::Window *pWindow (mrSlideSorter.GetContentWindow().get());
+    if ( ! pWindow)
+        return;
+
+    css::uno::Reference< css::accessibility::XAccessible >
+        xAccessible (pWindow->GetAccessible(false));
+    if ( ! xAccessible.is())
+        return;
+
+    // Now comes a small hack.  We assume that the accessible object is
+    // an instantiation of AccessibleSlideSorterView and cast it to that
+    // class.  The cleaner alternative to this cast would be a new member
+    // in which we would store the last AccessibleSlideSorterView object
+    // created by SlideSorterViewShell::CreateAccessibleDocumentView().
+    // But then there is no guaranty that the accessible object obtained
+    // from the window really is that instance last created by
+    // CreateAccessibleDocumentView().
+    // However, the dynamic cast together with the check of the result
+    // being NULL should be safe enough.
+    ::accessibility::AccessibleSlideSorterView* pAccessibleView
+            = dynamic_cast< ::accessibility::AccessibleSlideSorterView*>(xAccessible.get());
+    if (pAccessibleView == nullptr)
+        return;
+
+    ::accessibility::AccessibleSlideSorterObject* pChild
+            = pAccessibleView->GetAccessibleChildImplementation(nPageIndex);
+    if (pChild == nullptr || pChild->GetPage() == nullptr)
+        return;
+
+    OUString sNewName (pChild->GetPage()->GetName());
+    pChild->FireAccessibleEvent(
+        css::accessibility::AccessibleEventId::NAME_CHANGED,
+        Any(rsOldName),
+        Any(sNewName));
+}
+
+void SlideSorterController::SetDocumentSlides (const Reference<container::XIndexAccess>& rxSlides)
+{
+    if (mrModel.GetDocumentSlides() != rxSlides)
+    {
+        ModelChangeLock aLock (*this);
+        PreModelChange();
+
+        mrModel.SetDocumentSlides(rxSlides);
+    }
+}
+
+VisibleAreaManager& SlideSorterController::GetVisibleAreaManager() const
+{
+    OSL_ASSERT(mpVisibleAreaManager);
+    return *mpVisibleAreaManager;
+}
+
+void SlideSorterController::CheckForMasterPageAssignment()
+{
+    if (mrModel.GetPageCount()%2==0)
+        return;
+    PageEnumeration aAllPages (PageEnumerationProvider::CreateAllPagesEnumeration(mrModel));
+    while (aAllPages.HasMoreElements())
+    {
+        SharedPageDescriptor pDescriptor (aAllPages.GetNextElement());
+        if (pDescriptor->UpdateMasterPage())
+        {
+            mrView.GetPreviewCache()->InvalidatePreviewBitmap (
+                pDescriptor->GetPage());
+        }
+    }
+}
+
+void SlideSorterController::CheckForSlideTransitionAssignment()
+{
+    if (mrModel.GetPageCount()%2==0)
+        return;
+    PageEnumeration aAllPages (PageEnumerationProvider::CreateAllPagesEnumeration(mrModel));
+    while (aAllPages.HasMoreElements())
+    {
+        SharedPageDescriptor pDescriptor (aAllPages.GetNextElement());
+        if (pDescriptor->UpdateTransitionFlag())
+        {
+            mrView.GetPreviewCache()->InvalidatePreviewBitmap (
+                pDescriptor->GetPage());
+        }
+    }
+}
+
+//===== SlideSorterController::ModelChangeLock ================================
+
+SlideSorterController::ModelChangeLock::ModelChangeLock (
+    SlideSorterController& rController)
+    : mpController(&rController)
+{
+    mpController->LockModelChange();
+}
+
+SlideSorterController::ModelChangeLock::~ModelChangeLock() COVERITY_NOEXCEPT_FALSE
+{
+    Release();
+}
+
+void SlideSorterController::ModelChangeLock::Release()
+{
+    if (mpController != nullptr)
+    {
+        mpController->UnlockModelChange();
+        mpController = nullptr;
+    }
+}
+
+} // end of namespace ::sd::slidesorter
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/controller/SlsAnimationFunction.cxx b/sd/source/ui/slidesorter/controller/SlsAnimationFunction.cxx
new file mode 100644
index 000000000..31978baf7
--- /dev/null
+++ b/sd/source/ui/slidesorter/controller/SlsAnimationFunction.cxx
@@ -0,0 +1,129 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <sal/config.h>
+
+#include <o3tl/safeint.hxx>
+
+#include <controller/SlsAnimationFunction.hxx>
+
+namespace sd::slidesorter::controller {
+
+//===== AnimationBezierFunction ===============================================
+
+AnimationBezierFunction::AnimationBezierFunction (
+    const double nX1,
+    const double nY1)
+    : mnX1(nX1),
+      mnY1(nY1),
+      mnX2(1-nY1),
+      mnY2(1-nX1)
+{
+}
+
+::basegfx::B2DPoint AnimationBezierFunction::operator() (const double nT)
+{
+    return ::basegfx::B2DPoint(
+        EvaluateComponent(nT, mnX1, mnX2),
+        EvaluateComponent(nT, mnY1, mnY2));
+}
+
+double AnimationBezierFunction::EvaluateComponent (
+    const double nT,
+    const double nV1,
+    const double nV2)
+{
+    const double nS (1-nT);
+
+    // While the control point values 1 and 2 are explicitly given the start
+    // and end values are implicitly given.
+    const double nV0 (0);
+    const double nV3 (1);
+
+    const double nV01 (nS*nV0 + nT*nV1);
+    const double nV12 (nS*nV1 + nT*nV2);
+    const double nV23 (nS*nV2 + nT*nV3);
+
+    const double nV012 (nS*nV01 + nT*nV12);
+    const double nV123 (nS*nV12 + nT*nV23);
+
+    const double nV0123 (nS*nV012 + nT*nV123);
+
+    return nV0123;
+}
+
+//===== AnimationParametricFunction ===========================================
+
+AnimationParametricFunction::AnimationParametricFunction (const ParametricFunction& rFunction)
+{
+    const sal_Int32 nSampleCount (64);
+
+    // Sample the given parametric function.
+    ::std::vector<basegfx::B2DPoint> aPoints;
+    aPoints.reserve(nSampleCount);
+    for (sal_Int32 nIndex=0; nIndex<nSampleCount; ++nIndex)
+    {
+        const double nT (nIndex/double(nSampleCount-1));
+        aPoints.emplace_back(rFunction(nT));
+    }
+
+    // Interpolate at evenly spaced points.
+    maY.clear();
+    maY.reserve(nSampleCount);
+    double nX0 (aPoints[0].getX());
+    double nY0 (aPoints[0].getY());
+    double nX1 (aPoints[1].getX());
+    double nY1 (aPoints[1].getY());
+    sal_Int32 nIndex (1);
+    for (sal_Int32 nIndex2=0; nIndex2<nSampleCount; ++nIndex2)
+    {
+        const double nX (nIndex2 / double(nSampleCount-1));
+        while (nX > nX1 && nIndex<nSampleCount)
+        {
+            nX0 = nX1;
+            nY0 = nY1;
+            nX1 = aPoints[nIndex].getX();
+            nY1 = aPoints[nIndex].getY();
+            ++nIndex;
+        }
+        const double nU ((nX-nX1) / (nX0 - nX1));
+        const double nY (nY0*nU + nY1*(1-nU));
+        maY.push_back(nY);
+    }
+}
+
+double AnimationParametricFunction::operator() (const double nX)
+{
+    const sal_Int32 nIndex0 (static_cast<sal_Int32>(nX * maY.size()));
+    const double nX0 (nIndex0 / double(maY.size()-1));
+    const sal_uInt32 nIndex1 (nIndex0 + 1);
+    const double nX1 (nIndex1 / double(maY.size()-1));
+
+    if (nIndex0<=0)
+        return maY[0];
+    else if (o3tl::make_unsigned(nIndex0)>=maY.size() || nIndex1>=maY.size())
+        return maY[maY.size()-1];
+
+    const double nU ((nX-nX1) / (nX0 - nX1));
+    return maY[nIndex0]*nU + maY[nIndex1]*(1-nU);
+}
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/controller/SlsAnimator.cxx b/sd/source/ui/slidesorter/controller/SlsAnimator.cxx
new file mode 100644
index 000000000..b400ec4dc
--- /dev/null
+++ b/sd/source/ui/slidesorter/controller/SlsAnimator.cxx
@@ -0,0 +1,280 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <controller/SlsAnimator.hxx>
+#include <view/SlideSorterView.hxx>
+#include <osl/diagnose.h>
+
+namespace sd::slidesorter::controller {
+
+/** Handle one animation function by using a timer for frequent calls to
+    the animations operator().
+*/
+class Animator::Animation
+{
+public:
+    Animation (
+        const Animator::AnimationFunctor& rAnimation,
+        const double nStartOffset,
+        const double nDuration,
+        const double nGlobalTime,
+        const Animator::AnimationId nAnimationId,
+        const Animator::FinishFunctor& rFinishFunctor);
+    /** Run next animation step.  If animation has reached its end it is
+        expired.
+    */
+    bool Run (const double nGlobalTime);
+
+    /** Typically called when an animation has finished, but also from
+        Animator::Disposed().  The finish functor is called and the
+        animation is marked as expired to prevent another run.
+    */
+    void Expire();
+    bool IsExpired() const { return mbIsExpired;}
+
+    Animator::AnimationFunctor maAnimation;
+    Animator::FinishFunctor maFinishFunctor;
+    const Animator::AnimationId mnAnimationId;
+    const double mnDuration;
+    const double mnEnd;
+    const double mnGlobalTimeAtStart;
+    bool mbIsExpired;
+};
+
+Animator::Animator (SlideSorter& rSlideSorter)
+    : mrSlideSorter(rSlideSorter),
+      maIdle("sd slidesorter controller Animator"),
+      mbIsDisposed(false),
+      mnNextAnimationId(0)
+{
+    maIdle.SetPriority(TaskPriority::REPAINT);
+    maIdle.SetInvokeHandler(LINK(this,Animator,TimeoutHandler));
+}
+
+Animator::~Animator()
+{
+    if ( ! mbIsDisposed)
+    {
+        OSL_ASSERT(mbIsDisposed);
+        Dispose();
+    }
+}
+
+void Animator::Dispose()
+{
+    mbIsDisposed = true;
+
+    AnimationList aCopy (maAnimations);
+    for (const auto& rxAnimation : aCopy)
+        rxAnimation->Expire();
+
+    maIdle.Stop();
+    if (mpDrawLock)
+    {
+        mpDrawLock->Dispose();
+        mpDrawLock.reset();
+    }
+}
+
+Animator::AnimationId Animator::AddAnimation (
+    const AnimationFunctor& rAnimation,
+    const FinishFunctor& rFinishFunctor)
+{
+    // When the animator is already disposed then ignore this call
+    // silently (well, we show an assertion, but do not throw an exception.)
+    OSL_ASSERT( ! mbIsDisposed);
+    if (mbIsDisposed)
+        return -1;
+
+    std::shared_ptr<Animation> pAnimation =
+        std::make_shared<Animation>(
+            rAnimation,
+            0,
+            300 / 1000.0,
+            maElapsedTime.getElapsedTime(),
+            ++mnNextAnimationId,
+            rFinishFunctor);
+    maAnimations.push_back(pAnimation);
+
+    RequestNextFrame();
+
+    return pAnimation->mnAnimationId;
+}
+
+void Animator::RemoveAnimation (const Animator::AnimationId nId)
+{
+    OSL_ASSERT( ! mbIsDisposed);
+
+    const AnimationList::iterator iAnimation (::std::find_if(
+        maAnimations.begin(),
+        maAnimations.end(),
+        [nId] (std::shared_ptr<Animation> const& pAnim)
+            { return nId == pAnim->mnAnimationId; }));
+    if (iAnimation != maAnimations.end())
+    {
+        OSL_ASSERT((*iAnimation)->mnAnimationId == nId);
+        (*iAnimation)->Expire();
+        maAnimations.erase(iAnimation);
+    }
+
+    if (maAnimations.empty())
+    {
+        // Reset the animation id when we can.
+        mnNextAnimationId = 0;
+
+        // No more animations => we do not have to suppress painting
+        // anymore.
+        mpDrawLock.reset();
+    }
+}
+
+void Animator::RemoveAllAnimations()
+{
+    for (auto const& it : maAnimations)
+    {
+        it->Expire();
+    }
+    maAnimations.clear();
+    mnNextAnimationId = 0;
+
+    // No more animations => we do not have to suppress painting
+    // anymore.
+    mpDrawLock.reset();
+}
+
+bool Animator::ProcessAnimations (const double nTime)
+{
+    bool bExpired (false);
+
+    OSL_ASSERT( ! mbIsDisposed);
+    if (mbIsDisposed)
+        return bExpired;
+
+    AnimationList aCopy (maAnimations);
+    for (const auto& rxAnimation : aCopy)
+    {
+        bExpired |= rxAnimation->Run(nTime);
+    }
+
+    return bExpired;
+}
+
+void Animator::CleanUpAnimationList()
+{
+    OSL_ASSERT( ! mbIsDisposed);
+    if (mbIsDisposed)
+        return;
+
+    AnimationList aActiveAnimations;
+
+    for (const auto& rxAnimation : maAnimations)
+    {
+        if ( ! rxAnimation->IsExpired())
+            aActiveAnimations.push_back(rxAnimation);
+    }
+
+    maAnimations.swap(aActiveAnimations);
+}
+
+void Animator::RequestNextFrame ()
+{
+    if ( ! maIdle.IsActive())
+    {
+        // Prevent redraws except for the ones in TimeoutHandler.  While the
+        // Animator is active it will schedule repaints regularly.  Repaints
+        // in between would only lead to visual artifacts.
+        mpDrawLock.reset(new view::SlideSorterView::DrawLock(mrSlideSorter));
+        maIdle.Start();
+    }
+}
+
+IMPL_LINK_NOARG(Animator, TimeoutHandler, Timer *, void)
+{
+    if (mbIsDisposed)
+        return;
+
+    if (ProcessAnimations(maElapsedTime.getElapsedTime()))
+        CleanUpAnimationList();
+
+    // Unlock the draw lock.  This should lead to a repaint.
+    mpDrawLock.reset();
+
+    if (!maAnimations.empty())
+        RequestNextFrame();
+}
+
+//===== Animator::Animation ===================================================
+
+Animator::Animation::Animation (
+    const Animator::AnimationFunctor& rAnimation,
+    const double nStartOffset,
+    const double nDuration,
+    const double nGlobalTime,
+    const Animator::AnimationId nId,
+    const Animator::FinishFunctor& rFinishFunctor)
+    : maAnimation(rAnimation),
+      maFinishFunctor(rFinishFunctor),
+      mnAnimationId(nId),
+      mnDuration(nDuration),
+      mnEnd(nGlobalTime + nDuration + nStartOffset),
+      mnGlobalTimeAtStart(nGlobalTime + nStartOffset),
+      mbIsExpired(false)
+{
+    Run(nGlobalTime);
+}
+
+bool Animator::Animation::Run (const double nGlobalTime)
+{
+    if ( ! mbIsExpired)
+    {
+        if (mnDuration > 0)
+        {
+            if (nGlobalTime >= mnEnd)
+            {
+                maAnimation(1.0);
+                Expire();
+            }
+            else if (nGlobalTime >= mnGlobalTimeAtStart)
+            {
+                maAnimation((nGlobalTime - mnGlobalTimeAtStart) / mnDuration);
+            }
+        }
+        else if (mnDuration < 0)
+        {
+            // Animations without end have to be expired by their owner.
+            maAnimation(nGlobalTime);
+        }
+    }
+
+    return mbIsExpired;
+}
+
+void Animator::Animation::Expire()
+{
+    if ( ! mbIsExpired)
+    {
+        mbIsExpired = true;
+        if (maFinishFunctor)
+            maFinishFunctor();
+    }
+}
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/controller/SlsClipboard.cxx b/sd/source/ui/slidesorter/controller/SlsClipboard.cxx
new file mode 100644
index 000000000..160077e64
--- /dev/null
+++ b/sd/source/ui/slidesorter/controller/SlsClipboard.cxx
@@ -0,0 +1,918 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <sal/config.h>
+
+#include <cassert>
+
+#include <controller/SlsClipboard.hxx>
+
+#include <SlideSorterViewShell.hxx>
+#include <SlideSorter.hxx>
+#include <model/SlideSorterModel.hxx>
+#include <model/SlsPageDescriptor.hxx>
+#include <model/SlsPageEnumerationProvider.hxx>
+#include <view/SlideSorterView.hxx>
+#include <controller/SlideSorterController.hxx>
+#include <controller/SlsInsertionIndicatorHandler.hxx>
+#include <controller/SlsPageSelector.hxx>
+#include <controller/SlsSelectionFunction.hxx>
+#include <controller/SlsCurrentSlideManager.hxx>
+#include <controller/SlsFocusManager.hxx>
+#include <controller/SlsSelectionManager.hxx>
+#include <controller/SlsTransferableData.hxx>
+#include <controller/SlsSelectionObserver.hxx>
+#include <controller/SlsVisibleAreaManager.hxx>
+#include <cache/SlsPageCache.hxx>
+
+#include <ViewShellBase.hxx>
+#include <DrawViewShell.hxx>
+#include <Window.hxx>
+#include <fupoor.hxx>
+#include <strings.hrc>
+#include <sdresid.hxx>
+#include <sdxfer.hxx>
+#include <sdmod.hxx>
+#include <ins_paste.hxx>
+#include <drawdoc.hxx>
+#include <DrawDocShell.hxx>
+#include <sdpage.hxx>
+#include <sdtreelb.hxx>
+
+#include <com/sun/star/datatransfer/dnd/DNDConstants.hpp>
+#include <sfx2/request.hxx>
+#include <sfx2/viewfrm.hxx>
+#include <sfx2/bindings.hxx>
+#include <sfx2/docfile.hxx>
+#include <svx/svxids.hrc>
+#include <tools/urlobj.hxx>
+#include <rtl/ustring.hxx>
+#include <vcl/svapp.hxx>
+
+namespace sd::slidesorter::controller {
+
+namespace {
+/** Temporarily deactivate slide tracking of the VisibleAreaManager.
+    This is used as a workaround to avoid unwanted repositioning of
+    the visible area when the selection of slides is copied to the
+    clipboard (cloning of slides leads to model change notifications
+    for the original model.)
+*/
+class TemporarySlideTrackingDeactivator
+{
+public:
+    explicit TemporarySlideTrackingDeactivator (SlideSorterController& rController)
+        : mrController(rController),
+          mbIsCurrentSlideTrackingActive (
+              mrController.GetVisibleAreaManager().IsCurrentSlideTrackingActive())
+    {
+        if (mbIsCurrentSlideTrackingActive)
+            mrController.GetVisibleAreaManager().DeactivateCurrentSlideTracking();
+    }
+    ~TemporarySlideTrackingDeactivator()
+    {
+        if (mbIsCurrentSlideTrackingActive)
+            mrController.GetVisibleAreaManager().ActivateCurrentSlideTracking();
+    }
+
+private:
+    SlideSorterController& mrController;
+    const bool mbIsCurrentSlideTrackingActive;
+};
+} // end of anonymous namespace
+
+class Clipboard::UndoContext
+{
+public:
+    UndoContext (
+        SdDrawDocument* pDocument,
+        const std::shared_ptr<ViewShell>& rpMainViewShell)
+        : mpDocument(pDocument),
+          mpMainViewShell(rpMainViewShell)
+    {
+        if (mpDocument!=nullptr && mpDocument->IsUndoEnabled())
+        {
+            if (mpMainViewShell && mpMainViewShell->GetShellType() == ViewShell::ST_DRAW)
+                mpDocument->BegUndo(SdResId(STRING_DRAG_AND_DROP_PAGES));
+            else
+                mpDocument->BegUndo(SdResId(STRING_DRAG_AND_DROP_SLIDES));
+        }
+    }
+
+    ~UndoContext()
+    {
+        if (mpDocument!=nullptr && mpDocument->IsUndoEnabled())
+            mpDocument->EndUndo();
+        if (mpMainViewShell && mpMainViewShell->GetViewFrame()!=nullptr)
+        {
+            SfxBindings& rBindings = mpMainViewShell->GetViewFrame()->GetBindings();
+            rBindings.Invalidate(SID_UNDO);
+            rBindings.Invalidate(SID_REDO);
+        }
+    }
+private:
+    SdDrawDocument* mpDocument;
+    std::shared_ptr<ViewShell> mpMainViewShell;
+};
+
+Clipboard::Clipboard (SlideSorter& rSlideSorter)
+    : ViewClipboard(rSlideSorter.GetView()),
+      mrSlideSorter(rSlideSorter),
+      mrController(mrSlideSorter.GetController()),
+      mnDragFinishedUserEventId(nullptr)
+{
+}
+
+Clipboard::~Clipboard()
+{
+    if (mnDragFinishedUserEventId != nullptr)
+        Application::RemoveUserEvent(mnDragFinishedUserEventId);
+}
+
+/** With the current implementation the forwarded calls to the current
+    function will come back eventually to call the local Do(Cut|Copy|Paste)
+    methods.  A shortcut is possible but would be an unclean hack.
+*/
+void Clipboard::HandleSlotCall (SfxRequest& rRequest)
+{
+    ViewShell* pViewShell = mrSlideSorter.GetViewShell();
+    rtl::Reference<FuPoor> xFunc;
+    if (pViewShell != nullptr)
+        xFunc = pViewShell->GetCurrentFunction();
+    switch (rRequest.GetSlot())
+    {
+        case SID_CUT:
+            if (mrSlideSorter.GetModel().GetEditMode() != EditMode::MasterPage)
+            {
+                if(xFunc.is())
+                    xFunc->DoCut();
+                else
+                    DoCut();
+            }
+            rRequest.Done();
+            break;
+
+        case SID_COPY:
+            if (mrSlideSorter.GetModel().GetEditMode() != EditMode::MasterPage)
+            {
+                if(xFunc.is())
+                    xFunc->DoCopy();
+                else
+                    DoCopy();
+            }
+            rRequest.Done();
+            break;
+
+        case SID_PASTE:
+            // Prevent redraws while inserting pages from the clipboard
+            // because the intermediate inconsistent state might lead to
+            // a crash.
+            if (mrSlideSorter.GetModel().GetEditMode() != EditMode::MasterPage)
+            {
+                view::SlideSorterView::DrawLock aLock (mrSlideSorter);
+                SelectionObserver::Context aContext (mrSlideSorter);
+                if(xFunc.is())
+                    xFunc->DoPaste();
+                else
+                    DoPaste();
+            }
+            rRequest.Done();
+            break;
+
+        case SID_DELETE:
+            DoDelete();
+            rRequest.Done();
+            break;
+    }
+}
+
+void Clipboard::DoCut ()
+{
+    if (mrSlideSorter.GetModel().GetPageCount() > 1)
+    {
+        DoCopy();
+        DoDelete();
+    }
+}
+
+void Clipboard::DoDelete()
+{
+    if (mrSlideSorter.GetModel().GetPageCount() > 1)
+    {
+        mrController.GetSelectionManager()->DeleteSelectedPages();
+    }
+}
+
+void Clipboard::DoCopy ()
+{
+    CreateSlideTransferable( nullptr, false );
+}
+
+void Clipboard::DoPaste ()
+{
+    SdTransferable* pClipTransferable = SD_MOD()->pTransferClip;
+
+    if (pClipTransferable==nullptr || !pClipTransferable->IsPageTransferable())
+        return;
+
+    sal_Int32 nInsertPosition = GetInsertionPosition();
+
+    if (nInsertPosition >= 0)
+    {
+        // Paste the pages from the clipboard.
+        sal_Int32 nInsertPageCount = PasteTransferable(nInsertPosition);
+        // Select the pasted pages and make the first of them the
+        // current page.
+        mrSlideSorter.GetContentWindow()->GrabFocus();
+        SelectPageRange(nInsertPosition, nInsertPageCount);
+    }
+}
+
+sal_Int32 Clipboard::GetInsertionPosition ()
+{
+    sal_Int32 nInsertPosition = -1;
+
+    // Determine the insertion position:
+    // a) When the insertion indicator is visible, then at that position.
+    // b) When the focus indicator is visible, then before or after the
+    // focused page, depending on user input to a dialog.
+    // c) When there is a selection but no focus, then after the
+    // selection.
+    // d) After the last page when there is no selection and no focus.
+
+    std::shared_ptr<controller::InsertionIndicatorHandler> pInsertionIndicatorHandler (
+        mrController.GetInsertionIndicatorHandler());
+    if (pInsertionIndicatorHandler->IsActive())
+    {
+        // Use the insertion index of an active insertion indicator.
+        nInsertPosition = pInsertionIndicatorHandler->GetInsertionPageIndex();
+    }
+    else if (mrController.GetSelectionManager()->GetInsertionPosition() >= 0)
+    {
+        // Use the insertion index of an insertion indicator that has been
+        // deactivated a short while ago.
+        nInsertPosition = mrController.GetSelectionManager()->GetInsertionPosition();
+    }
+    else if (mrController.GetFocusManager().IsFocusShowing())
+    {
+        // Use the focus to determine the insertion position.
+        vcl::Window* pWin = mrSlideSorter.GetContentWindow();
+        SdInsertPasteDlg aDialog(pWin ? pWin->GetFrameWeld() : nullptr);
+        if (aDialog.run() == RET_OK)
+        {
+            nInsertPosition = mrController.GetFocusManager().GetFocusedPageIndex();
+            if (!aDialog.IsInsertBefore())
+                nInsertPosition ++;
+        }
+    }
+
+    return nInsertPosition;
+}
+
+sal_Int32 Clipboard::PasteTransferable (sal_Int32 nInsertPosition)
+{
+    SdTransferable* pClipTransferable = SD_MOD()->pTransferClip;
+    model::SlideSorterModel& rModel (mrSlideSorter.GetModel());
+    bool bMergeMasterPages = !pClipTransferable->HasSourceDoc (rModel.GetDocument());
+    sal_uInt16 nInsertIndex (rModel.GetCoreIndex(nInsertPosition));
+    sal_Int32 nInsertPageCount (0);
+    if (pClipTransferable->HasPageBookmarks())
+    {
+        const std::vector<OUString> &rBookmarkList = pClipTransferable->GetPageBookmarks();
+        const SolarMutexGuard aGuard;
+
+        nInsertPageCount = static_cast<sal_uInt16>(rBookmarkList.size());
+        rModel.GetDocument()->InsertBookmarkAsPage(
+            rBookmarkList,
+            nullptr,
+            false,
+            false,
+            nInsertIndex,
+            false,
+            pClipTransferable->GetPageDocShell(),
+            true,
+            bMergeMasterPages,
+            false);
+    }
+    else
+    {
+        SfxObjectShell* pShell = pClipTransferable->GetDocShell().get();
+        DrawDocShell* pDataDocSh = static_cast<DrawDocShell*>(pShell);
+        SdDrawDocument* pDataDoc = pDataDocSh->GetDoc();
+
+        if (pDataDoc!=nullptr
+            && pDataDoc->GetSdPageCount(PageKind::Standard))
+        {
+            const SolarMutexGuard aGuard;
+
+            bMergeMasterPages = (pDataDoc != rModel.GetDocument());
+            nInsertPageCount = pDataDoc->GetSdPageCount( PageKind::Standard );
+            rModel.GetDocument()->InsertBookmarkAsPage(
+                std::vector<OUString>(),
+                nullptr,
+                false,
+                false,
+                nInsertIndex,
+                false,
+                pDataDocSh,
+                true,
+                bMergeMasterPages,
+                false);
+        }
+    }
+    mrController.HandleModelChange();
+    return nInsertPageCount;
+}
+
+void Clipboard::SelectPageRange (sal_Int32 nFirstIndex, sal_Int32 nPageCount)
+{
+    // Select the newly inserted pages.  That are the nInsertPageCount pages
+    // after the nInsertIndex position.
+    PageSelector& rSelector (mrController.GetPageSelector());
+    rSelector.DeselectAllPages();
+    for (sal_Int32 i=0; i<nPageCount; i++)
+    {
+        model::SharedPageDescriptor pDescriptor (
+            mrSlideSorter.GetModel().GetPageDescriptor(nFirstIndex + i));
+        if (pDescriptor)
+        {
+            rSelector.SelectPage(pDescriptor);
+            // The first page of the new selection is made the current page.
+            if (i == 0)
+            {
+                mrController.GetCurrentSlideManager()->SwitchCurrentSlide(pDescriptor);
+            }
+        }
+    }
+}
+
+void Clipboard::CreateSlideTransferable (
+    vcl::Window* pWindow,
+    bool bDrag)
+{
+    std::vector<OUString> aBookmarkList;
+
+    // Insert all selected pages into a bookmark list and remember them in
+    // maPagesToRemove for possible later removal.
+    model::PageEnumeration aSelectedPages
+        (model::PageEnumerationProvider::CreateSelectedPagesEnumeration(
+            mrSlideSorter.GetModel()));
+    SdDrawDocument* const pDocument = mrSlideSorter.GetModel().GetDocument();
+    DrawDocShell* const pDataDocSh = pDocument->GetDocSh();
+
+    sal_Int32 nUniqueID = 0;
+    while (aSelectedPages.HasMoreElements())
+    {
+        model::SharedPageDescriptor pDescriptor (aSelectedPages.GetNextElement());
+
+        //ensure that the slides have unique names
+        const OUString sOrigName = pDescriptor->GetPage()->GetName();
+        if ( pDataDocSh && !pDataDocSh->IsPageNameUnique( sOrigName ) )
+        {
+            OUString sUniqueName;
+            bool bUnique = false;
+            while ( !bUnique )
+            {
+                sUniqueName = sOrigName + "_clipboard" + OUString::number(nUniqueID++);
+                bUnique = pDataDocSh->IsNewPageNameValid( sUniqueName );
+                if ( bUnique )
+                    pDescriptor->GetPage()->SetName(sUniqueName);
+            }
+        }
+
+        aBookmarkList.push_back(pDescriptor->GetPage()->GetName());
+        maPagesToRemove.push_back (pDescriptor->GetPage());
+    }
+
+    // Create a small set of representatives of the selection for which
+    // previews are included into the transferable so that an insertion
+    // indicator can be rendered.
+    aSelectedPages.Rewind();
+    ::std::vector<TransferableData::Representative> aRepresentatives;
+    aRepresentatives.reserve(3);
+    std::shared_ptr<cache::PageCache> pPreviewCache (
+        mrSlideSorter.GetView().GetPreviewCache());
+    while (aSelectedPages.HasMoreElements())
+    {
+        model::SharedPageDescriptor pDescriptor (aSelectedPages.GetNextElement());
+        if ( ! pDescriptor || pDescriptor->GetPage()==nullptr)
+            continue;
+        BitmapEx aPreview (pPreviewCache->GetPreviewBitmap(pDescriptor->GetPage(), false));
+        aRepresentatives.emplace_back(
+            aPreview,
+            pDescriptor->HasState(model::PageDescriptor::ST_Excluded));
+        if (aRepresentatives.size() >= 3)
+            break;
+    }
+
+    if (aBookmarkList.empty())
+        return;
+
+    mrSlideSorter.GetView().BrkAction();
+    rtl::Reference<SdTransferable> pTransferable = TransferableData::CreateTransferable (
+        pDocument,
+        dynamic_cast<SlideSorterViewShell*>(mrSlideSorter.GetViewShell()),
+        std::move(aRepresentatives));
+
+    if (bDrag)
+        SD_MOD()->pTransferDrag = pTransferable.get();
+    else
+        SD_MOD()->pTransferClip = pTransferable.get();
+
+    pDocument->CreatingDataObj (pTransferable.get());
+    pTransferable->SetWorkDocument(pDocument->AllocSdDrawDocument());
+    std::unique_ptr<TransferableObjectDescriptor> pObjDesc(new TransferableObjectDescriptor);
+    pTransferable->GetWorkDocument()->GetDocSh()
+        ->FillTransferableObjectDescriptor (*pObjDesc);
+
+    if (pDataDocSh != nullptr)
+        pObjDesc->maDisplayName = pDataDocSh->GetMedium()->GetURLObject().GetURLNoPass();
+
+    vcl::Window* pActionWindow = pWindow;
+    if (pActionWindow == nullptr)
+    {
+        ViewShell* pViewShell = mrSlideSorter.GetViewShell();
+        if (pViewShell != nullptr)
+            pActionWindow = pViewShell->GetActiveWindow();
+    }
+
+    assert(pActionWindow);
+
+    pTransferable->SetStartPos (pActionWindow->PixelToLogic(
+        pActionWindow->GetPointerPosPixel()));
+    pTransferable->SetObjectDescriptor (std::move(pObjDesc));
+
+    {
+        TemporarySlideTrackingDeactivator aDeactivator (mrController);
+        pTransferable->SetPageBookmarks (std::move(aBookmarkList), !bDrag);
+    }
+
+    if (bDrag)
+    {
+        pTransferable->SetView (&mrSlideSorter.GetView());
+        pTransferable->StartDrag (pActionWindow, DND_ACTION_COPY | DND_ACTION_MOVE);
+    }
+    else
+        pTransferable->CopyToClipboard (pActionWindow);
+
+    pDocument->CreatingDataObj(nullptr);
+}
+
+std::shared_ptr<SdTransferable::UserData> Clipboard::CreateTransferableUserData (SdTransferable* pTransferable)
+{
+    do
+    {
+        SdPageObjsTLV::SdPageObjsTransferable* pTreeListBoxTransferable
+            = dynamic_cast<SdPageObjsTLV::SdPageObjsTransferable*>(pTransferable);
+        if (pTreeListBoxTransferable == nullptr)
+            break;
+
+        // Find view shell for the document of the transferable.
+        ::sd::ViewShell* pViewShell
+              = SdPageObjsTLV::GetViewShellForDocShell(pTreeListBoxTransferable->GetDocShell());
+        if (pViewShell == nullptr)
+            break;
+
+        // Find slide sorter for the document of the transferable.
+        SlideSorterViewShell* pSlideSorterViewShell
+            = SlideSorterViewShell::GetSlideSorter(pViewShell->GetViewShellBase());
+        if (pSlideSorterViewShell == nullptr)
+            break;
+        SlideSorter& rSlideSorter (pSlideSorterViewShell->GetSlideSorter());
+
+        // Get bookmark from transferable.
+        TransferableDataHelper  aDataHelper (pTransferable);
+        INetBookmark aINetBookmark;
+        if ( ! aDataHelper.GetINetBookmark(SotClipboardFormatId::NETSCAPE_BOOKMARK, aINetBookmark))
+            break;
+        const OUString sURL (aINetBookmark.GetURL());
+        const sal_Int32 nIndex (sURL.indexOf('#'));
+        if (nIndex == -1)
+            break;
+        OUString sBookmark (sURL.copy(nIndex+1));
+
+        // Make sure that the bookmark points to a page.
+        SdDrawDocument* pTransferableDocument = rSlideSorter.GetModel().GetDocument();
+        if (pTransferableDocument == nullptr)
+            break;
+        bool bIsMasterPage = false;
+        const sal_uInt16 nPageIndex (pTransferableDocument->GetPageByName(sBookmark, bIsMasterPage));
+        if (nPageIndex == SDRPAGE_NOTFOUND)
+            break;
+
+        // Create preview.
+        ::std::vector<TransferableData::Representative> aRepresentatives;
+        aRepresentatives.reserve(1);
+        std::shared_ptr<cache::PageCache> pPreviewCache (
+            rSlideSorter.GetView().GetPreviewCache());
+        model::SharedPageDescriptor pDescriptor (rSlideSorter.GetModel().GetPageDescriptor((nPageIndex-1)/2));
+        if ( ! pDescriptor || pDescriptor->GetPage()==nullptr)
+            break;
+        BitmapEx aPreview (pPreviewCache->GetPreviewBitmap(pDescriptor->GetPage(), false));
+        aRepresentatives.emplace_back(
+                aPreview,
+                pDescriptor->HasState(model::PageDescriptor::ST_Excluded));
+
+        // Remember the page in maPagesToRemove so that it can be removed
+        // when drag and drop action is "move".
+        Clipboard& rOtherClipboard (pSlideSorterViewShell->GetSlideSorter().GetController().GetClipboard());
+        rOtherClipboard.maPagesToRemove.clear();
+        rOtherClipboard.maPagesToRemove.push_back(pDescriptor->GetPage());
+
+        // Create the new transferable.
+        std::shared_ptr<SdTransferable::UserData> pNewTransferable =
+            std::make_shared<TransferableData>(
+                pSlideSorterViewShell,
+                std::move(aRepresentatives));
+        pTransferable->SetWorkDocument(pTreeListBoxTransferable->GetSourceDoc()->AllocSdDrawDocument());
+        //        pTransferable->SetView(&mrSlideSorter.GetView());
+
+        // Set page bookmark list.
+        std::vector<OUString> aPageBookmarks { sBookmark };
+        pTransferable->SetPageBookmarks(std::move(aPageBookmarks), false);
+
+        // Replace the view referenced by the transferable with the
+        // corresponding slide sorter view.
+        pTransferable->SetView(&pSlideSorterViewShell->GetSlideSorter().GetView());
+
+        return pNewTransferable;
+    }
+    while (false);
+
+    return std::shared_ptr<SdTransferable::UserData>();
+}
+
+void Clipboard::StartDrag (
+    const Point& rPosition,
+    vcl::Window* pWindow)
+{
+    maPagesToRemove.clear();
+    CreateSlideTransferable(pWindow, true);
+
+    mrController.GetInsertionIndicatorHandler()->UpdatePosition(
+        rPosition,
+        InsertionIndicatorHandler::UnknownMode);
+}
+
+void Clipboard::DragFinished (sal_Int8 nDropAction)
+{
+    if (mnDragFinishedUserEventId == nullptr)
+    {
+        mnDragFinishedUserEventId = Application::PostUserEvent(
+            LINK(this, Clipboard, ProcessDragFinished),
+            reinterpret_cast<void*>(nDropAction));
+    }
+}
+
+IMPL_LINK(Clipboard, ProcessDragFinished, void*, pUserData, void)
+{
+    const sal_Int8 nDropAction (static_cast<sal_Int8>(reinterpret_cast<sal_IntPtr>(pUserData)));
+
+    mnDragFinishedUserEventId = nullptr;
+
+    // Hide the substitution display and insertion indicator.
+    ::rtl::Reference<SelectionFunction> pFunction (mrController.GetCurrentSelectionFunction());
+    if (pFunction.is())
+        pFunction->NotifyDragFinished();
+
+    PageSelector& rSelector (mrController.GetPageSelector());
+    if ((nDropAction & DND_ACTION_MOVE) != 0
+        && ! maPagesToRemove.empty())
+    {
+        // Remove the pages that have been moved to another place (possibly
+        // in the same document.)
+        rSelector.DeselectAllPages();
+        for (const auto& rpDraggedPage : maPagesToRemove)
+        {
+            rSelector.SelectPage(rpDraggedPage);
+        }
+        mrController.GetSelectionManager()->DeleteSelectedPages();
+    }
+    mxUndoContext.reset();
+    mxSelectionObserverContext.reset();
+}
+
+sal_Int8 Clipboard::AcceptDrop (
+    const AcceptDropEvent& rEvent,
+    DropTargetHelper& rTargetHelper,
+    ::sd::Window* pTargetWindow,
+    sal_uInt16 nPage,
+    SdrLayerID nLayer)
+{
+    sal_Int8 nAction (DND_ACTION_NONE);
+
+    const Clipboard::DropType eDropType (IsDropAccepted());
+
+    switch (eDropType)
+    {
+        case DT_PAGE:
+        case DT_PAGE_FROM_NAVIGATOR:
+        {
+            // Accept a drop.
+            nAction = rEvent.mnAction;
+
+            // Use the copy action when the drop action is the default, i.e. not
+            // explicitly set to move or link, and when the source and
+            // target models are not the same.
+            SdTransferable* pDragTransferable = SD_MOD()->pTransferDrag;
+            if (pDragTransferable != nullptr
+                && pDragTransferable->IsPageTransferable()
+                && ((rEvent.maDragEvent.DropAction
+                        & css::datatransfer::dnd::DNDConstants::ACTION_DEFAULT) != 0)
+                && (mrSlideSorter.GetModel().GetDocument()->GetDocSh()
+                    != pDragTransferable->GetPageDocShell()))
+            {
+                nAction = DND_ACTION_COPY;
+            }
+            else if (IsInsertionTrivial(pDragTransferable, nAction))
+            {
+                nAction = DND_ACTION_NONE;
+            }
+
+            // Show the insertion marker and the substitution for a drop.
+            SelectionFunction* pSelectionFunction = dynamic_cast<SelectionFunction*>(
+                mrSlideSorter.GetViewShell()->GetCurrentFunction().get());
+            if (pSelectionFunction != nullptr)
+                pSelectionFunction->MouseDragged(rEvent, nAction);
+
+            // Scroll the window when the mouse reaches the window border.
+            //            mrController.GetScrollBarManager().AutoScroll (rEvent.maPosPixel);
+        }
+        break;
+
+        case DT_SHAPE:
+            nAction = ExecuteOrAcceptShapeDrop(
+                DC_ACCEPT,
+                rEvent.maPosPixel,
+                &rEvent,
+                rTargetHelper,
+                pTargetWindow,
+                nPage,
+                nLayer);
+            break;
+
+        default:
+        case DT_NONE:
+            nAction = DND_ACTION_NONE;
+            break;
+    }
+
+    return nAction;
+}
+
+sal_Int8 Clipboard::ExecuteDrop (
+    const ExecuteDropEvent& rEvent,
+    DropTargetHelper& rTargetHelper,
+    ::sd::Window* pTargetWindow,
+    sal_uInt16 nPage,
+    SdrLayerID nLayer)
+{
+    sal_Int8 nResult = DND_ACTION_NONE;
+    mxUndoContext.reset();
+    const Clipboard::DropType eDropType (IsDropAccepted());
+
+    switch (eDropType)
+    {
+        case DT_PAGE:
+        case DT_PAGE_FROM_NAVIGATOR:
+        {
+            SdTransferable* pDragTransferable = SD_MOD()->pTransferDrag;
+            const Point aEventModelPosition (
+                pTargetWindow->PixelToLogic (rEvent.maPosPixel));
+            const sal_Int32 nXOffset (std::abs (pDragTransferable->GetStartPos().X()
+                - aEventModelPosition.X()));
+            const sal_Int32 nYOffset (std::abs (pDragTransferable->GetStartPos().Y()
+                - aEventModelPosition.Y()));
+            bool bContinue =
+                ( pDragTransferable->GetView() != &mrSlideSorter.GetView() )
+                || ( nXOffset >= 2 && nYOffset >= 2 );
+
+            std::shared_ptr<InsertionIndicatorHandler> pInsertionIndicatorHandler(
+                        mrController.GetInsertionIndicatorHandler());
+            // Get insertion position and then turn off the insertion indicator.
+            pInsertionIndicatorHandler->UpdatePosition(aEventModelPosition, rEvent.mnAction);
+            //            sal_uInt16 nIndex = DetermineInsertPosition(*pDragTransferable);
+
+            // Do not process the insertion when it is trivial,
+            // i.e. would insert pages at their original place.
+            if (IsInsertionTrivial(pDragTransferable, rEvent.mnAction))
+                bContinue = false;
+
+            // Tell the insertion indicator handler to hide before the model
+            // is modified.  Doing it later may result in page objects whose
+            // animation state is not properly reset because they are then
+            // in another run then before the model change.
+            pInsertionIndicatorHandler->End(Animator::AM_Immediate);
+
+            if (bContinue)
+            {
+                SlideSorterController::ModelChangeLock aModelChangeLock (mrController);
+
+                // Handle a general drop operation.
+                mxUndoContext.reset(new UndoContext (
+                    mrSlideSorter.GetModel().GetDocument(),
+                    mrSlideSorter.GetViewShell()->GetViewShellBase().GetMainViewShell()));
+                mxSelectionObserverContext.reset(new SelectionObserver::Context(mrSlideSorter));
+
+                if (rEvent.mnAction == DND_ACTION_MOVE)
+                {
+                    SdDrawDocument* pDoc = mrSlideSorter.GetModel().GetDocument();
+                    const bool bDoesMakePageObjectsNamesUnique = pDoc->DoesMakePageObjectsNamesUnique();
+                    pDoc->DoMakePageObjectsNamesUnique(false);
+                    HandlePageDrop(*pDragTransferable);
+                    pDoc->DoMakePageObjectsNamesUnique(bDoesMakePageObjectsNamesUnique);
+                }
+                else
+                    HandlePageDrop(*pDragTransferable);
+
+                nResult = rEvent.mnAction;
+
+                // We leave the undo context alive for when moving or
+                // copying inside one view then the actions in
+                // NotifyDragFinished should be covered as well as
+                // well as the ones above.
+            }
+
+            // When the pages originated in another slide sorter then
+            // only that is notified automatically about the drag
+            // operation being finished.  Because the target slide sorter
+            // has be notified, too, add a callback for that.
+            std::shared_ptr<TransferableData> pSlideSorterTransferable (
+                TransferableData::GetFromTransferable(pDragTransferable));
+            assert(pSlideSorterTransferable);
+            if (pSlideSorterTransferable
+                && pSlideSorterTransferable->GetSourceViewShell() != mrSlideSorter.GetViewShell())
+            {
+                DragFinished(nResult);
+            }
+
+            // Notify the receiving selection function that drag-and-drop is
+            // finished and the substitution handler can be released.
+            ::rtl::Reference<SelectionFunction> pFunction (
+                mrController.GetCurrentSelectionFunction());
+            if (pFunction.is())
+                pFunction->NotifyDragFinished();
+        }
+        break;
+
+        case DT_SHAPE:
+            nResult = ExecuteOrAcceptShapeDrop(
+                DC_EXECUTE,
+                rEvent.maPosPixel,
+                &rEvent,
+                rTargetHelper,
+                pTargetWindow,
+                nPage,
+                nLayer);
+            break;
+
+        default:
+        case DT_NONE:
+            break;
+    }
+
+    return nResult;
+}
+
+bool Clipboard::IsInsertionTrivial (
+    SdTransferable const * pTransferable,
+    const sal_Int8 nDndAction) const
+{
+    std::shared_ptr<TransferableData> pSlideSorterTransferable (
+        TransferableData::GetFromTransferable(pTransferable));
+    if (pSlideSorterTransferable
+        && pSlideSorterTransferable->GetSourceViewShell() != mrSlideSorter.GetViewShell())
+        return false;
+    return mrController.GetInsertionIndicatorHandler()->IsInsertionTrivial(nDndAction);
+}
+
+void Clipboard::Abort()
+{
+    if (mxSelectionObserverContext)
+    {
+        mxSelectionObserverContext->Abort();
+        mxSelectionObserverContext.reset();
+    }
+}
+
+sal_uInt16 Clipboard::DetermineInsertPosition ()
+{
+    // Tell the model to move the dragged pages behind the one with the
+    // index nInsertionIndex which first has to be transformed into an index
+    // understandable by the document.
+    const sal_Int32 nInsertionIndex (
+        mrController.GetInsertionIndicatorHandler()->GetInsertionPageIndex());
+
+    // Convert to insertion index to that of an SdModel.
+    if (nInsertionIndex >= 0)
+        return mrSlideSorter.GetModel().GetCoreIndex(nInsertionIndex);
+    else
+        return 0;
+}
+
+Clipboard::DropType Clipboard::IsDropAccepted() const
+{
+    const SdTransferable* pDragTransferable = SD_MOD()->pTransferDrag;
+    if (pDragTransferable == nullptr)
+        return DT_NONE;
+
+    if (pDragTransferable->IsPageTransferable())
+    {
+        if (mrSlideSorter.GetModel().GetEditMode() != EditMode::MasterPage)
+            return DT_PAGE;
+        else
+            return DT_NONE;
+    }
+
+    const SdPageObjsTLV::SdPageObjsTransferable* pPageObjsTransferable
+        = dynamic_cast<const SdPageObjsTLV::SdPageObjsTransferable*>(pDragTransferable);
+    if (pPageObjsTransferable != nullptr)
+        return DT_PAGE_FROM_NAVIGATOR;
+
+    return DT_SHAPE;
+}
+
+sal_Int8 Clipboard::ExecuteOrAcceptShapeDrop (
+    DropCommand eCommand,
+    const Point& rPosition,
+    const void* pDropEvent,
+    DropTargetHelper& rTargetHelper,
+    ::sd::Window* pTargetWindow,
+    sal_uInt16 nPage,
+    SdrLayerID nLayer)
+{
+    sal_Int8 nResult = 0;
+
+    // The dropping of a shape is accepted or executed only when there is
+    // DrawViewShell available to which we can forward this call.  This has
+    // technical reasons:  The actual code to accept or execute a shape drop
+    // is implemented in the ViewShell class and uses the page view of the
+    // main edit view.  This is not possible without a DrawViewShell.
+    std::shared_ptr<DrawViewShell> pDrawViewShell;
+    if (mrSlideSorter.GetViewShell() != nullptr)
+        pDrawViewShell = std::dynamic_pointer_cast<DrawViewShell>(
+            mrSlideSorter.GetViewShell()->GetViewShellBase().GetMainViewShell());
+    if (pDrawViewShell != nullptr
+        && (pDrawViewShell->GetShellType() == ViewShell::ST_IMPRESS
+            || pDrawViewShell->GetShellType() == ViewShell::ST_DRAW))
+    {
+        // The drop is only accepted or executed when it takes place over a
+        // page object.  Therefore we replace a missing page number by the
+        // number of the page under the mouse.
+        if (nPage == SDRPAGE_NOTFOUND)
+        {
+            model::SharedPageDescriptor pDescriptor (
+                mrSlideSorter.GetModel().GetPageDescriptor(
+                    mrSlideSorter.GetView().GetPageIndexAtPoint(rPosition)));
+            if (pDescriptor)
+                nPage = pDescriptor->GetPageIndex();
+        }
+
+        // Now comes the code that is different for the Execute and Accept:
+        // We simply forward the call to the AcceptDrop() or ExecuteDrop()
+        // methods of the DrawViewShell in the center pane.
+        if (nPage != SDRPAGE_NOTFOUND)
+            switch (eCommand)
+            {
+                case DC_ACCEPT:
+                    nResult = pDrawViewShell->AcceptDrop(
+                        *static_cast<const AcceptDropEvent*>(pDropEvent),
+                        rTargetHelper,
+                        pTargetWindow,
+                        nPage,
+                        nLayer);
+                    break;
+
+                case DC_EXECUTE:
+                    nResult = pDrawViewShell->ExecuteDrop(
+                        *static_cast<const ExecuteDropEvent*>(pDropEvent),
+                        rTargetHelper,
+                        pTargetWindow,
+                        nPage,
+                        nLayer);
+                    break;
+            }
+    }
+
+    return nResult;
+}
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/controller/SlsCurrentSlideManager.cxx b/sd/source/ui/slidesorter/controller/SlsCurrentSlideManager.cxx
new file mode 100644
index 000000000..9203c06e8
--- /dev/null
+++ b/sd/source/ui/slidesorter/controller/SlsCurrentSlideManager.cxx
@@ -0,0 +1,256 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <SlideSorter.hxx>
+#include <model/SlideSorterModel.hxx>
+#include <model/SlsPageDescriptor.hxx>
+#include <controller/SlsPageSelector.hxx>
+#include <controller/SlideSorterController.hxx>
+#include <controller/SlsCurrentSlideManager.hxx>
+#include <controller/SlsFocusManager.hxx>
+#include <view/SlideSorterView.hxx>
+#include <ViewShellBase.hxx>
+#include <ViewShell.hxx>
+#include <DrawViewShell.hxx>
+#include <sdpage.hxx>
+#include <FrameView.hxx>
+#include <com/sun/star/beans/XPropertySet.hpp>
+#include <com/sun/star/frame/XController.hpp>
+#include <osl/diagnose.h>
+
+using namespace ::com::sun::star;
+using namespace ::com::sun::star::uno;
+
+using namespace ::sd::slidesorter::model;
+
+namespace sd::slidesorter::controller {
+
+CurrentSlideManager::CurrentSlideManager (SlideSorter& rSlideSorter)
+    : mrSlideSorter(rSlideSorter),
+      mnCurrentSlideIndex(-1),
+      maSwitchPageDelayTimer("sd CurrentSlideManager maSwitchPageDelayTimer")
+{
+    maSwitchPageDelayTimer.SetTimeout(100);
+    maSwitchPageDelayTimer.SetInvokeHandler(LINK(this,CurrentSlideManager,SwitchPageCallback));
+}
+
+CurrentSlideManager::~CurrentSlideManager()
+{
+}
+
+void CurrentSlideManager::NotifyCurrentSlideChange (const SdPage* pPage)
+{
+    if (pPage != nullptr)
+        NotifyCurrentSlideChange(
+            mrSlideSorter.GetModel().GetIndex(
+                Reference<drawing::XDrawPage>(
+                    const_cast<SdPage*>(pPage)->getUnoPage(),
+                    UNO_QUERY)));
+    else
+        NotifyCurrentSlideChange(-1);
+}
+
+void CurrentSlideManager::NotifyCurrentSlideChange (const sal_Int32 nSlideIndex)
+{
+    if (mnCurrentSlideIndex == nSlideIndex)
+        return;
+
+    PageSelector::BroadcastLock aBroadcastLock (mrSlideSorter.GetController().GetPageSelector());
+
+    mrSlideSorter.GetController().GetPageSelector().DeselectAllPages();
+
+    ReleaseCurrentSlide();
+    AcquireCurrentSlide(nSlideIndex);
+
+    // Update the selection.
+    if (mpCurrentSlide)
+    {
+        mrSlideSorter.GetController().GetPageSelector().SelectPage(mpCurrentSlide);
+        mrSlideSorter.GetController().GetFocusManager().SetFocusedPage(mpCurrentSlide);
+    }
+}
+
+void CurrentSlideManager::ReleaseCurrentSlide()
+{
+    if (mpCurrentSlide)
+        mrSlideSorter.GetView().SetState(mpCurrentSlide, PageDescriptor::ST_Current, false);
+
+    mpCurrentSlide.reset();
+    mnCurrentSlideIndex = -1;
+}
+
+void CurrentSlideManager::AcquireCurrentSlide (const sal_Int32 nSlideIndex)
+{
+    mnCurrentSlideIndex = nSlideIndex;
+
+    // if current slide valid
+    if (mnCurrentSlideIndex >= 0 && mnCurrentSlideIndex<mrSlideSorter.GetModel().GetPageCount())
+    {
+        // Get a descriptor for the XDrawPage reference.  Note that the
+        // given XDrawPage may or may not be member of the slide sorter
+        // document.
+        mpCurrentSlide = mrSlideSorter.GetModel().GetPageDescriptor(mnCurrentSlideIndex);
+        if (mpCurrentSlide)
+            mrSlideSorter.GetView().SetState(mpCurrentSlide, PageDescriptor::ST_Current, true);
+    }
+}
+
+void CurrentSlideManager::SwitchCurrentSlide (
+    const sal_Int32 nSlideIndex)
+{
+    SwitchCurrentSlide(mrSlideSorter.GetModel().GetPageDescriptor(nSlideIndex), true/*bUpdateSelection*/);
+}
+
+void CurrentSlideManager::SwitchCurrentSlide (
+    const SharedPageDescriptor& rpDescriptor,
+    const bool bUpdateSelection)
+{
+    if (!rpDescriptor || mpCurrentSlide==rpDescriptor)
+        return;
+
+    ReleaseCurrentSlide();
+    AcquireCurrentSlide((rpDescriptor->GetPage()->GetPageNum()-1)/2);
+
+    ViewShell* pViewShell = mrSlideSorter.GetViewShell();
+    if (pViewShell != nullptr && pViewShell->IsMainViewShell())
+    {
+        // The slide sorter is the main view.
+        FrameView* pFrameView = pViewShell->GetFrameView();
+        if (pFrameView != nullptr)
+            pFrameView->SetSelectedPage(sal::static_int_cast<sal_uInt16>(mnCurrentSlideIndex));
+        mrSlideSorter.GetController().GetPageSelector().SetCoreSelection();
+    }
+
+    // We do not tell the XController/ViewShellBase about the new
+    // slide right away.  This is done asynchronously after a short
+    // delay to allow for more slide switches in the slide sorter.
+    // This goes under the assumption that slide switching inside
+    // the slide sorter is fast (no expensive redraw of the new page
+    // (unless the preview of the new slide is not yet preset)) and
+    // that slide switching in the edit view is slow (all shapes of
+    // the new slide have to be repainted.)
+    maSwitchPageDelayTimer.Start();
+
+    // We have to store the (index of the) new current slide at
+    // the tab control because there are other asynchronous
+    // notifications of the slide switching that otherwise
+    // overwrite the correct value.
+    SetCurrentSlideAtTabControl(mpCurrentSlide);
+
+    if (bUpdateSelection)
+    {
+        mrSlideSorter.GetController().GetPageSelector().DeselectAllPages();
+        mrSlideSorter.GetController().GetPageSelector().SelectPage(rpDescriptor);
+    }
+    mrSlideSorter.GetController().GetFocusManager().SetFocusedPage(rpDescriptor);
+}
+
+void CurrentSlideManager::SetCurrentSlideAtViewShellBase (const SharedPageDescriptor& rpDescriptor)
+{
+    OSL_ASSERT(rpDescriptor);
+
+    ViewShellBase* pBase = mrSlideSorter.GetViewShellBase();
+    if (pBase != nullptr)
+    {
+        DrawViewShell* pDrawViewShell = dynamic_cast<DrawViewShell*>(
+            pBase->GetMainViewShell().get());
+        if (pDrawViewShell != nullptr)
+        {
+            sal_uInt16 nPageNumber = (rpDescriptor->GetPage()->GetPageNum()-1)/2;
+            pDrawViewShell->SwitchPage(nPageNumber);
+            TabControl& rPageTabControl = pDrawViewShell->GetPageTabControl();
+            rPageTabControl.SetCurPageId(rPageTabControl.GetPageId(nPageNumber));
+        }
+    }
+}
+
+void CurrentSlideManager::SetCurrentSlideAtTabControl (const SharedPageDescriptor& rpDescriptor)
+{
+    OSL_ASSERT(rpDescriptor);
+
+    ViewShellBase* pBase = mrSlideSorter.GetViewShellBase();
+    if (pBase != nullptr)
+    {
+        std::shared_ptr<DrawViewShell> pDrawViewShell (
+            std::dynamic_pointer_cast<DrawViewShell>(pBase->GetMainViewShell()));
+        if (pDrawViewShell)
+        {
+            sal_uInt16 nPageNumber = (rpDescriptor->GetPage()->GetPageNum()-1)/2;
+            TabControl& rPageTabControl = pDrawViewShell->GetPageTabControl();
+            rPageTabControl.SetCurPageId(rPageTabControl.GetPageId(nPageNumber));
+        }
+    }
+}
+
+void CurrentSlideManager::SetCurrentSlideAtXController (const SharedPageDescriptor& rpDescriptor)
+{
+    OSL_ASSERT(rpDescriptor);
+
+    try
+    {
+        Reference<beans::XPropertySet> xSet (mrSlideSorter.GetXController(), UNO_QUERY);
+        if (xSet.is())
+        {
+            Any aPage;
+            aPage <<= rpDescriptor->GetPage()->getUnoPage();
+            xSet->setPropertyValue( "CurrentPage", aPage );
+        }
+    }
+    catch (const Exception&)
+    {
+        // We have not been able to set the current page at the main view.
+        // This is sad but still leaves us in a valid state.  Therefore,
+        // this exception is silently ignored.
+    }
+}
+
+void CurrentSlideManager::PrepareModelChange()
+{
+    mpCurrentSlide.reset();
+}
+
+void CurrentSlideManager::HandleModelChange()
+{
+    if (mnCurrentSlideIndex >= 0)
+    {
+        mpCurrentSlide = mrSlideSorter.GetModel().GetPageDescriptor(mnCurrentSlideIndex);
+        if (mpCurrentSlide)
+            mrSlideSorter.GetView().SetState(mpCurrentSlide, PageDescriptor::ST_Current, true);
+    }
+}
+
+IMPL_LINK_NOARG(CurrentSlideManager, SwitchPageCallback, Timer *, void)
+{
+    if (mpCurrentSlide)
+    {
+        // Set current page.  At the moment we have to do this in two
+        // different ways.  The UNO way is the preferable one but, alas,
+        // it does not work always correctly (after some kinds of model
+        // changes).  Therefore, we call DrawViewShell::SwitchPage(),
+        // too.
+        ViewShell* pViewShell = mrSlideSorter.GetViewShell();
+        if (pViewShell==nullptr || ! pViewShell->IsMainViewShell())
+            SetCurrentSlideAtViewShellBase(mpCurrentSlide);
+        SetCurrentSlideAtXController(mpCurrentSlide);
+    }
+}
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/controller/SlsDragAndDropContext.cxx b/sd/source/ui/slidesorter/controller/SlsDragAndDropContext.cxx
new file mode 100644
index 000000000..f447c5656
--- /dev/null
+++ b/sd/source/ui/slidesorter/controller/SlsDragAndDropContext.cxx
@@ -0,0 +1,120 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "SlsDragAndDropContext.hxx"
+
+#include <SlideSorter.hxx>
+#include <model/SlideSorterModel.hxx>
+#include <controller/SlideSorterController.hxx>
+#include <controller/SlsInsertionIndicatorHandler.hxx>
+#include <controller/SlsScrollBarManager.hxx>
+#include <controller/SlsProperties.hxx>
+#include <controller/SlsClipboard.hxx>
+#include <controller/SlsTransferableData.hxx>
+#include <Window.hxx>
+#include <sdtreelb.hxx>
+#include <sdmod.hxx>
+
+namespace sd::slidesorter::controller {
+
+DragAndDropContext::DragAndDropContext (SlideSorter& rSlideSorter)
+    : mpTargetSlideSorter(&rSlideSorter),
+      mnInsertionIndex(-1)
+{
+    // No Drag-and-Drop for master pages.
+    if (rSlideSorter.GetModel().GetEditMode() != EditMode::Page)
+        return;
+
+    // For properly handling transferables created by the navigator we
+    // need additional information.  For this a user data object is
+    // created that contains the necessary information.
+    SdTransferable* pTransferable = SD_MOD()->pTransferDrag;
+    SdPageObjsTLV::SdPageObjsTransferable* pTreeListBoxTransferable
+        = dynamic_cast<SdPageObjsTLV::SdPageObjsTransferable*>(pTransferable);
+    if (pTreeListBoxTransferable!=nullptr && !TransferableData::GetFromTransferable(pTransferable))
+    {
+        pTransferable->AddUserData(
+            sd::slidesorter::controller::Clipboard::CreateTransferableUserData(pTransferable));
+    }
+
+    rSlideSorter.GetController().GetInsertionIndicatorHandler()->UpdateIndicatorIcon(pTransferable);
+}
+
+DragAndDropContext::~DragAndDropContext() COVERITY_NOEXCEPT_FALSE
+{
+    SetTargetSlideSorter();
+}
+
+void DragAndDropContext::Dispose()
+{
+    mnInsertionIndex = -1;
+}
+
+void DragAndDropContext::UpdatePosition (
+    const Point& rMousePosition,
+    const InsertionIndicatorHandler::Mode eMode,
+    const bool bAllowAutoScroll)
+{
+    if (mpTargetSlideSorter == nullptr)
+        return;
+
+    if (mpTargetSlideSorter->GetProperties()->IsUIReadOnly())
+        return;
+
+    // Convert window coordinates into model coordinates (we need the
+    // window coordinates for auto-scrolling because that remains
+    // constant while scrolling.)
+    sd::Window *pWindow = mpTargetSlideSorter->GetContentWindow().get();
+    const Point aMouseModelPosition (pWindow->PixelToLogic(rMousePosition));
+    std::shared_ptr<InsertionIndicatorHandler> pInsertionIndicatorHandler (
+        mpTargetSlideSorter->GetController().GetInsertionIndicatorHandler());
+
+    bool bDoAutoScroll = bAllowAutoScroll
+            && mpTargetSlideSorter->GetController().GetScrollBarManager().AutoScroll(
+                rMousePosition,
+                [this, eMode, rMousePosition] () {
+                    return this->UpdatePosition(rMousePosition, eMode, false);
+                });
+
+    if (!bDoAutoScroll)
+    {
+        pInsertionIndicatorHandler->UpdatePosition(aMouseModelPosition, eMode);
+
+        // Remember the new insertion index.
+        mnInsertionIndex = pInsertionIndicatorHandler->GetInsertionPageIndex();
+        if (pInsertionIndicatorHandler->IsInsertionTrivial(mnInsertionIndex, eMode))
+            mnInsertionIndex = -1;
+    }
+}
+
+void DragAndDropContext::SetTargetSlideSorter()
+{
+    if (mpTargetSlideSorter != nullptr)
+    {
+        mpTargetSlideSorter->GetController().GetScrollBarManager().StopAutoScroll();
+        mpTargetSlideSorter->GetController().GetInsertionIndicatorHandler()->End(
+            Animator::AM_Animated);
+    }
+
+    mpTargetSlideSorter = nullptr;
+}
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/controller/SlsDragAndDropContext.hxx b/sd/source/ui/slidesorter/controller/SlsDragAndDropContext.hxx
new file mode 100644
index 000000000..cbeb11f8b
--- /dev/null
+++ b/sd/source/ui/slidesorter/controller/SlsDragAndDropContext.hxx
@@ -0,0 +1,68 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <controller/SlsInsertionIndicatorHandler.hxx>
+
+class Point;
+
+namespace sd::slidesorter
+{
+class SlideSorter;
+}
+
+namespace sd::slidesorter::controller
+{
+/** A DragAndDropContext object handles an active drag and drop operation.
+    When the mouse is moved from one slide sorter window to another the
+    target SlideSorter object is exchanged accordingly.
+*/
+class DragAndDropContext
+{
+public:
+    /** Create a substitution display of the currently selected pages or,
+        when provided, the pages in the transferable.
+    */
+    explicit DragAndDropContext(SlideSorter& rSlideSorter);
+    ~DragAndDropContext() COVERITY_NOEXCEPT_FALSE;
+
+    /** Call this method (for example as reaction to ESC key press) to avoid
+        processing (ie moving or inserting) the substitution when the called
+        DragAndDropContext object is destroyed.
+    */
+    void Dispose();
+
+    /** Move the substitution display by the distance the mouse has
+        travelled since the last call to this method or to
+        CreateSubstitution().  The given point becomes the new anchor.
+    */
+    void UpdatePosition(const Point& rMousePosition, const InsertionIndicatorHandler::Mode eMode,
+                        const bool bAllowAutoScroll);
+
+    void SetTargetSlideSorter();
+
+private:
+    SlideSorter* mpTargetSlideSorter;
+    sal_Int32 mnInsertionIndex;
+};
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/controller/SlsFocusManager.cxx b/sd/source/ui/slidesorter/controller/SlsFocusManager.cxx
new file mode 100644
index 000000000..59027f5a8
--- /dev/null
+++ b/sd/source/ui/slidesorter/controller/SlsFocusManager.cxx
@@ -0,0 +1,245 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <controller/SlsFocusManager.hxx>
+
+#include <SlideSorter.hxx>
+#include <controller/SlideSorterController.hxx>
+#include <controller/SlsCurrentSlideManager.hxx>
+#include <controller/SlsVisibleAreaManager.hxx>
+#include <model/SlideSorterModel.hxx>
+#include <model/SlsPageDescriptor.hxx>
+#include <view/SlideSorterView.hxx>
+#include <view/SlsLayouter.hxx>
+#include <osl/diagnose.h>
+
+#include <Window.hxx>
+#include <sdpage.hxx>
+
+namespace sd::slidesorter::controller {
+
+FocusManager::FocusManager (SlideSorter& rSlideSorter)
+    : mrSlideSorter(rSlideSorter),
+      mnPageIndex(0),
+      mbPageIsFocused(false)
+{
+    if (mrSlideSorter.GetModel().GetPageCount() > 0)
+        mnPageIndex = 0;
+}
+
+FocusManager::~FocusManager()
+{
+}
+
+void FocusManager::MoveFocus (FocusMoveDirection eDirection)
+{
+    if (!(mnPageIndex >= 0 && mbPageIsFocused))
+        return;
+
+    HideFocusIndicator (GetFocusedPageDescriptor());
+
+    const sal_Int32 nColumnCount (mrSlideSorter.GetView().GetLayouter().GetColumnCount());
+    const sal_Int32 nPageCount (mrSlideSorter.GetModel().GetPageCount());
+    switch (eDirection)
+    {
+        case FocusMoveDirection::Left:
+            if (mnPageIndex > 0)
+                mnPageIndex -= 1;
+            break;
+
+        case FocusMoveDirection::Right:
+            if (mnPageIndex < nPageCount-1)
+                mnPageIndex += 1;
+            break;
+
+        case FocusMoveDirection::Up:
+        {
+            const sal_Int32 nCandidate (mnPageIndex - nColumnCount);
+            if (nCandidate >= 0)
+            {
+                // Move the focus the previous row.
+                mnPageIndex = nCandidate;
+            }
+        }
+        break;
+
+        case FocusMoveDirection::Down:
+        {
+            const sal_Int32 nCandidate (mnPageIndex + nColumnCount);
+            if (nCandidate < nPageCount)
+            {
+                // Move the focus to the next row.
+                mnPageIndex = nCandidate;
+            }
+        }
+        break;
+    }
+
+    if (mnPageIndex < 0)
+    {
+        OSL_ASSERT(mnPageIndex>=0);
+        mnPageIndex = 0;
+    }
+    else if (mnPageIndex >= nPageCount)
+    {
+        OSL_ASSERT(mnPageIndex<nPageCount);
+        mnPageIndex = nPageCount - 1;
+    }
+
+    if (mbPageIsFocused)
+    {
+        ShowFocusIndicator(GetFocusedPageDescriptor(), true);
+    }
+}
+
+void FocusManager::ShowFocus (const bool bScrollToFocus)
+{
+    mbPageIsFocused = true;
+    ShowFocusIndicator(GetFocusedPageDescriptor(), bScrollToFocus);
+}
+
+void FocusManager::HideFocus()
+{
+    mbPageIsFocused = false;
+    HideFocusIndicator(GetFocusedPageDescriptor());
+}
+
+bool FocusManager::ToggleFocus()
+{
+    if (mnPageIndex >= 0)
+    {
+        if (mbPageIsFocused)
+            HideFocus ();
+        else
+            ShowFocus ();
+    }
+    return mbPageIsFocused;
+}
+
+bool FocusManager::HasFocus() const
+{
+    return mrSlideSorter.GetContentWindow()->HasFocus();
+}
+
+model::SharedPageDescriptor FocusManager::GetFocusedPageDescriptor() const
+{
+    return mrSlideSorter.GetModel().GetPageDescriptor(mnPageIndex);
+}
+
+bool FocusManager::SetFocusedPage (const model::SharedPageDescriptor& rpDescriptor)
+{
+    if (rpDescriptor)
+    {
+        FocusHider aFocusHider (*this);
+        mnPageIndex = (rpDescriptor->GetPage()->GetPageNum()-1)/2;
+        return true;
+    }
+    return false;
+}
+
+void FocusManager::SetFocusedPage (sal_Int32 nPageIndex)
+{
+    FocusHider aFocusHider (*this);
+    mnPageIndex = nPageIndex;
+}
+
+bool FocusManager::SetFocusedPageToCurrentPage()
+{
+    return SetFocusedPage(mrSlideSorter.GetController().GetCurrentSlideManager()->GetCurrentSlide());
+}
+
+bool FocusManager::IsFocusShowing() const
+{
+    return HasFocus() && mbPageIsFocused;
+}
+
+void FocusManager::HideFocusIndicator (const model::SharedPageDescriptor& rpDescriptor)
+{
+    if (rpDescriptor)
+    {
+        mrSlideSorter.GetView().SetState(rpDescriptor, model::PageDescriptor::ST_Focused, false);
+
+        // Hide focus should also fire the focus event, Currently, only accessibility add the focus listener
+        NotifyFocusChangeListeners();
+    }
+}
+
+void FocusManager::ShowFocusIndicator (
+    const model::SharedPageDescriptor& rpDescriptor,
+    const bool bScrollToFocus)
+{
+    if (!rpDescriptor)
+        return;
+
+    mrSlideSorter.GetView().SetState(rpDescriptor, model::PageDescriptor::ST_Focused, true);
+
+    if (bScrollToFocus)
+    {
+        // Scroll the focused page object into the visible area and repaint
+        // it, so that the focus indicator becomes visible.
+        mrSlideSorter.GetController().GetVisibleAreaManager().RequestVisible(rpDescriptor,true);
+    }
+    mrSlideSorter.GetView().RequestRepaint(rpDescriptor);
+
+    NotifyFocusChangeListeners();
+}
+
+void FocusManager::AddFocusChangeListener (const Link<LinkParamNone*,void>& rListener)
+{
+    if (::std::find (maFocusChangeListeners.begin(), maFocusChangeListeners.end(), rListener)
+        == maFocusChangeListeners.end())
+    {
+        maFocusChangeListeners.push_back (rListener);
+    }
+}
+
+void FocusManager::RemoveFocusChangeListener (const Link<LinkParamNone*,void>& rListener)
+{
+    maFocusChangeListeners.erase (
+        ::std::find (maFocusChangeListeners.begin(), maFocusChangeListeners.end(), rListener));
+}
+
+void FocusManager::NotifyFocusChangeListeners() const
+{
+    // Create a copy of the listener list to be safe when that is modified.
+    ::std::vector<Link<LinkParamNone*,void>> aListeners (maFocusChangeListeners);
+
+    // Tell the selection change listeners that the selection has changed.
+    for (const auto& rListener : aListeners)
+    {
+        rListener.Call(nullptr);
+    }
+}
+
+FocusManager::FocusHider::FocusHider (FocusManager& rManager)
+: mbFocusVisible(rManager.IsFocusShowing())
+, mrManager(rManager)
+{
+    mrManager.HideFocus();
+}
+
+FocusManager::FocusHider::~FocusHider() COVERITY_NOEXCEPT_FALSE
+{
+    if (mbFocusVisible)
+        mrManager.ShowFocus();
+}
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/controller/SlsInsertionIndicatorHandler.cxx b/sd/source/ui/slidesorter/controller/SlsInsertionIndicatorHandler.cxx
new file mode 100644
index 000000000..ff1a05ef1
--- /dev/null
+++ b/sd/source/ui/slidesorter/controller/SlsInsertionIndicatorHandler.cxx
@@ -0,0 +1,243 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <controller/SlsInsertionIndicatorHandler.hxx>
+#include <view/SlideSorterView.hxx>
+#include <view/SlsLayouter.hxx>
+#include <view/SlsInsertAnimator.hxx>
+#include <view/SlsInsertionIndicatorOverlay.hxx>
+#include <model/SlideSorterModel.hxx>
+#include <model/SlsPageEnumerationProvider.hxx>
+#include <com/sun/star/datatransfer/dnd/DNDConstants.hpp>
+#include <osl/diagnose.h>
+
+#include <SlideSorter.hxx>
+
+using namespace ::com::sun::star::datatransfer::dnd::DNDConstants;
+
+namespace sd::slidesorter::controller {
+
+InsertionIndicatorHandler::InsertionIndicatorHandler (SlideSorter& rSlideSorter)
+    : mrSlideSorter(rSlideSorter),
+      mpInsertionIndicatorOverlay(std::make_shared<view::InsertionIndicatorOverlay>(rSlideSorter)),
+      meMode(MoveMode),
+      mbIsInsertionTrivial(false),
+      mbIsActive(false),
+      mbIsReadOnly(mrSlideSorter.GetModel().IsReadOnly()),
+      mbIsOverSourceView(true),
+      maIconSize(0,0),
+      mbIsForcedShow(false)
+{
+}
+
+InsertionIndicatorHandler::~InsertionIndicatorHandler() COVERITY_NOEXCEPT_FALSE
+{
+}
+
+void InsertionIndicatorHandler::Start (const bool bIsOverSourceView)
+{
+    if (mbIsActive)
+    {
+        OSL_ASSERT(!mbIsActive);
+    }
+
+    mbIsReadOnly = mrSlideSorter.GetModel().IsReadOnly();
+    if (mbIsReadOnly)
+        return;
+
+    mbIsActive = true;
+    mbIsOverSourceView = bIsOverSourceView;
+}
+
+void InsertionIndicatorHandler::End (const controller::Animator::AnimationMode eMode)
+{
+    if (mbIsForcedShow ||  ! mbIsActive || mbIsReadOnly)
+        return;
+
+    GetInsertAnimator()->Reset(eMode);
+
+    mbIsActive = false;
+    //    maInsertPosition = view::InsertPosition();
+    meMode = UnknownMode;
+
+    mpInsertionIndicatorOverlay->Hide();
+    mpInsertionIndicatorOverlay = std::make_shared<view::InsertionIndicatorOverlay>(mrSlideSorter);
+}
+
+void InsertionIndicatorHandler::ForceShow()
+{
+    mbIsForcedShow = true;
+}
+
+void InsertionIndicatorHandler::ForceEnd()
+{
+    mbIsForcedShow = false;
+    End(Animator::AM_Immediate);
+}
+
+void InsertionIndicatorHandler::UpdateIndicatorIcon (const SdTransferable* pTransferable)
+{
+    mpInsertionIndicatorOverlay->Create(pTransferable);
+    maIconSize = mpInsertionIndicatorOverlay->GetSize();
+}
+
+InsertionIndicatorHandler::Mode InsertionIndicatorHandler::GetModeFromDndAction (
+    const sal_Int8 nDndAction)
+{
+    if ((nDndAction & ACTION_MOVE) != 0)
+        return MoveMode;
+    else if ((nDndAction & ACTION_COPY) != 0)
+        return CopyMode;
+    else
+        return UnknownMode;
+}
+
+void InsertionIndicatorHandler::UpdatePosition (
+    const Point& rMouseModelPosition,
+    const Mode eMode)
+{
+    if ( ! mbIsActive)
+        return;
+
+    if (mbIsReadOnly)
+        return;
+
+    SetPosition(rMouseModelPosition, eMode);
+}
+
+void InsertionIndicatorHandler::UpdatePosition (
+    const Point& rMouseModelPosition,
+    const sal_Int8 nDndAction)
+{
+    UpdatePosition(rMouseModelPosition, GetModeFromDndAction(nDndAction));
+}
+
+sal_Int32 InsertionIndicatorHandler::GetInsertionPageIndex() const
+{
+    if (mbIsReadOnly)
+        return -1;
+    else
+        return maInsertPosition.GetIndex();
+}
+
+void InsertionIndicatorHandler::SetPosition (
+    const Point& rPoint,
+    const Mode eMode)
+{
+    view::Layouter& rLayouter (mrSlideSorter.GetView().GetLayouter());
+
+    const view::InsertPosition aInsertPosition (rLayouter.GetInsertPosition(
+        rPoint,
+        maIconSize,
+        mrSlideSorter.GetModel()));
+
+    if (maInsertPosition == aInsertPosition && meMode == eMode)
+        return;
+
+    maInsertPosition = aInsertPosition;
+    meMode = eMode;
+    mbIsInsertionTrivial = IsInsertionTrivial(maInsertPosition.GetIndex(), eMode);
+    if (maInsertPosition.GetIndex()>=0 && ! mbIsInsertionTrivial)
+    {
+        mpInsertionIndicatorOverlay->SetLocation(maInsertPosition.GetLocation());
+
+        GetInsertAnimator()->SetInsertPosition(maInsertPosition);
+        mpInsertionIndicatorOverlay->Show();
+    }
+    else
+    {
+        GetInsertAnimator()->Reset(Animator::AM_Animated);
+        mpInsertionIndicatorOverlay->Hide();
+    }
+}
+
+std::shared_ptr<view::InsertAnimator> const & InsertionIndicatorHandler::GetInsertAnimator()
+{
+    if ( ! mpInsertAnimator)
+        mpInsertAnimator = std::make_shared<view::InsertAnimator>(mrSlideSorter);
+    return mpInsertAnimator;
+}
+
+bool InsertionIndicatorHandler::IsInsertionTrivial (
+    const sal_Int32 nInsertionIndex,
+    const Mode eMode) const
+{
+    if (eMode == CopyMode)
+        return false;
+    else if (eMode == UnknownMode)
+        return true;
+
+    if ( ! mbIsOverSourceView)
+        return false;
+
+    // Iterate over all selected pages and check whether there are
+    // holes.  While we do this we remember the indices of the first and
+    // last selected page as preparation for the next step.
+    sal_Int32 nCurrentIndex = -1;
+    sal_Int32 nFirstIndex = -1;
+    sal_Int32 nLastIndex = -1;
+    model::PageEnumeration aSelectedPages (
+        model::PageEnumerationProvider::CreateSelectedPagesEnumeration(
+            mrSlideSorter.GetModel()));
+    while (aSelectedPages.HasMoreElements())
+    {
+        model::SharedPageDescriptor pDescriptor (aSelectedPages.GetNextElement());
+
+        // Get the page number and compare it to the last one.
+        const sal_Int32 nPageNumber (pDescriptor->GetPageIndex());
+        if (nCurrentIndex>=0 && nPageNumber>(nCurrentIndex+1))
+            return false;
+        else
+            nCurrentIndex = nPageNumber;
+
+        // Remember indices of the first and last page of the selection.
+        if (nFirstIndex == -1)
+            nFirstIndex = nPageNumber;
+        nLastIndex = nPageNumber;
+    }
+
+    // When we come here then the selection has no holes.  We still have
+    // to check that the insertion position is not directly in front or
+    // directly behind the selection and thus moving the selection there
+    // would not change the model.
+    return nInsertionIndex >= nFirstIndex && nInsertionIndex <= (nLastIndex+1);
+}
+
+bool InsertionIndicatorHandler::IsInsertionTrivial (const sal_Int8 nDndAction)
+{
+    return IsInsertionTrivial(GetInsertionPageIndex(), GetModeFromDndAction(nDndAction));
+}
+
+//===== InsertionIndicatorHandler::ForceShowContext ===========================
+
+InsertionIndicatorHandler::ForceShowContext::ForceShowContext (
+    const std::shared_ptr<InsertionIndicatorHandler>& rpHandler)
+    : mpHandler(rpHandler)
+{
+    mpHandler->ForceShow();
+}
+
+InsertionIndicatorHandler::ForceShowContext::~ForceShowContext() COVERITY_NOEXCEPT_FALSE
+{
+    mpHandler->ForceEnd();
+}
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/controller/SlsListener.cxx b/sd/source/ui/slidesorter/controller/SlsListener.cxx
new file mode 100644
index 000000000..000f42da2
--- /dev/null
+++ b/sd/source/ui/slidesorter/controller/SlsListener.cxx
@@ -0,0 +1,597 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "SlsListener.hxx"
+
+#include <SlideSorter.hxx>
+#include <ViewShell.hxx>
+#include <ViewShellHint.hxx>
+#include <controller/SlideSorterController.hxx>
+#include <controller/SlsPageSelector.hxx>
+#include <controller/SlsCurrentSlideManager.hxx>
+#include <controller/SlsSelectionManager.hxx>
+#include <controller/SlsSelectionObserver.hxx>
+#include <model/SlideSorterModel.hxx>
+#include <view/SlideSorterView.hxx>
+#include <cache/SlsPageCache.hxx>
+#include <cache/SlsPageCacheManager.hxx>
+#include <drawdoc.hxx>
+#include <sdpage.hxx>
+#include <DrawDocShell.hxx>
+#include <svx/svdpage.hxx>
+
+#include <ViewShellBase.hxx>
+#include <EventMultiplexer.hxx>
+#include <com/sun/star/document/XEventBroadcaster.hpp>
+#include <com/sun/star/beans/XPropertySet.hpp>
+#include <com/sun/star/frame/FrameActionEvent.hpp>
+#include <com/sun/star/frame/FrameAction.hpp>
+#include <tools/debug.hxx>
+#include <tools/diagnose_ex.h>
+
+using namespace ::com::sun::star::accessibility;
+using namespace ::com::sun::star::beans;
+using namespace ::com::sun::star::uno;
+using namespace ::com::sun::star;
+
+namespace sd::slidesorter::controller {
+
+Listener::Listener (
+    SlideSorter& rSlideSorter)
+    : mrSlideSorter(rSlideSorter),
+      mrController(mrSlideSorter.GetController()),
+      mpBase(mrSlideSorter.GetViewShellBase()),
+      mbListeningToDocument (false),
+      mbListeningToUNODocument (false),
+      mbListeningToController (false),
+      mbListeningToFrame (false),
+      mbIsMainViewChangePending(false)
+{
+    StartListening(*mrSlideSorter.GetModel().GetDocument());
+    StartListening(*mrSlideSorter.GetModel().GetDocument()->GetDocSh());
+    mbListeningToDocument = true;
+
+    // Connect to the UNO document.
+    Reference<document::XEventBroadcaster> xBroadcaster (
+        mrSlideSorter.GetModel().GetDocument()->getUnoModel(), uno::UNO_QUERY);
+    if (xBroadcaster.is())
+    {
+        xBroadcaster->addEventListener (this);
+        mbListeningToUNODocument = true;
+    }
+
+    // Listen for disposing events from the document.
+    Reference<XComponent> xComponent (xBroadcaster, UNO_QUERY);
+    if (xComponent.is())
+        xComponent->addEventListener (
+            Reference<lang::XEventListener>(
+                static_cast<XWeak*>(this), UNO_QUERY));
+
+    // Connect to the frame to listen for controllers being exchanged.
+    bool bIsMainViewShell (false);
+    ViewShell* pViewShell = mrSlideSorter.GetViewShell();
+    if (pViewShell != nullptr)
+        bIsMainViewShell = pViewShell->IsMainViewShell();
+    if ( ! bIsMainViewShell)
+    {
+        // Listen to changes of certain properties.
+        Reference<frame::XFrame> xFrame;
+        Reference<frame::XController> xController (mrSlideSorter.GetXController());
+        if (xController.is())
+            xFrame = xController->getFrame();
+        mxFrameWeak = xFrame;
+        if (xFrame.is())
+        {
+            xFrame->addFrameActionListener(Reference<frame::XFrameActionListener>(this));
+            mbListeningToFrame = true;
+        }
+
+        // Connect to the current controller.
+        ConnectToController ();
+    }
+
+    // Listen for hints of the MainViewShell as well.  If that is not yet
+    // present then the EventMultiplexer will tell us when it is available.
+    if (mpBase != nullptr)
+    {
+        ViewShell* pMainViewShell = mpBase->GetMainViewShell().get();
+        if (pMainViewShell != nullptr
+            && pMainViewShell!=pViewShell)
+        {
+            StartListening(*pMainViewShell);
+        }
+
+        Link<tools::EventMultiplexerEvent&,void> aLink (LINK(this, Listener, EventMultiplexerCallback));
+        mpBase->GetEventMultiplexer()->AddEventListener(aLink);
+    }
+}
+
+Listener::~Listener()
+{
+    DBG_ASSERT( !mbListeningToDocument && !mbListeningToUNODocument && !mbListeningToFrame,
+        "sd::Listener::~Listener(), disposing() was not called, ask DBO!" );
+}
+
+void Listener::ReleaseListeners()
+{
+    if (mbListeningToDocument)
+    {
+        EndListening(*mrSlideSorter.GetModel().GetDocument()->GetDocSh());
+        EndListening(*mrSlideSorter.GetModel().GetDocument());
+        mbListeningToDocument = false;
+    }
+
+    if (mbListeningToUNODocument)
+    {
+        Reference<document::XEventBroadcaster> xBroadcaster (
+            mrSlideSorter.GetModel().GetDocument()->getUnoModel(), UNO_QUERY);
+        if (xBroadcaster.is())
+            xBroadcaster->removeEventListener (this);
+
+        // Remove the dispose listener.
+        Reference<XComponent> xComponent (xBroadcaster, UNO_QUERY);
+        if (xComponent.is())
+            xComponent->removeEventListener (
+                Reference<lang::XEventListener>(
+                    static_cast<XWeak*>(this), UNO_QUERY));
+
+        mbListeningToUNODocument = false;
+    }
+
+    if (mbListeningToFrame)
+    {
+        // Listen to changes of certain properties.
+        Reference<frame::XFrame> xFrame (mxFrameWeak);
+        if (xFrame.is())
+        {
+            xFrame->removeFrameActionListener(Reference<frame::XFrameActionListener>(this));
+            mbListeningToFrame = false;
+        }
+    }
+
+    DisconnectFromController ();
+
+    if (mpBase != nullptr)
+    {
+        Link<sd::tools::EventMultiplexerEvent&,void> aLink (LINK(this, Listener, EventMultiplexerCallback));
+        mpBase->GetEventMultiplexer()->RemoveEventListener(aLink);
+    }
+}
+
+void Listener::ConnectToController()
+{
+    ViewShell* pShell = mrSlideSorter.GetViewShell();
+
+    // Register at the controller of the main view shell (if we are that not
+    // ourself).
+    if (pShell!=nullptr && pShell->IsMainViewShell())
+        return;
+
+    Reference<frame::XController> xController (mrSlideSorter.GetXController());
+
+    // Listen to changes of certain properties.
+    Reference<beans::XPropertySet> xSet (xController, UNO_QUERY);
+    if (xSet.is())
+    {
+        try
+        {
+            xSet->addPropertyChangeListener("CurrentPage", this);
+        }
+        catch (beans::UnknownPropertyException&)
+        {
+            DBG_UNHANDLED_EXCEPTION("sd");
+        }
+        try
+        {
+            xSet->addPropertyChangeListener("IsMasterPageMode", this);
+        }
+        catch (beans::UnknownPropertyException&)
+        {
+            DBG_UNHANDLED_EXCEPTION("sd");
+        }
+    }
+
+    // Listen for disposing events.
+    if (xController.is())
+    {
+        xController->addEventListener (
+            Reference<lang::XEventListener>(static_cast<XWeak*>(this), UNO_QUERY));
+
+        mxControllerWeak = xController;
+        mbListeningToController = true;
+    }
+}
+
+void Listener::DisconnectFromController()
+{
+    if (!mbListeningToController)
+        return;
+
+    Reference<frame::XController> xController = mxControllerWeak;
+    Reference<beans::XPropertySet> xSet (xController, UNO_QUERY);
+    try
+    {
+        // Remove the property listener.
+        if (xSet.is())
+        {
+            xSet->removePropertyChangeListener( "CurrentPage", this );
+            xSet->removePropertyChangeListener( "IsMasterPageMode", this);
+        }
+
+        // Remove the dispose listener.
+        if (xController.is())
+            xController->removeEventListener (
+                Reference<lang::XEventListener>(
+                    static_cast<XWeak*>(this), UNO_QUERY));
+    }
+    catch (beans::UnknownPropertyException&)
+    {
+        DBG_UNHANDLED_EXCEPTION("sd");
+    }
+
+    mbListeningToController = false;
+    mxControllerWeak = Reference<frame::XController>();
+}
+
+void Listener::Notify (
+    SfxBroadcaster& rBroadcaster,
+    const SfxHint& rHint)
+{
+    if (rHint.GetId() == SfxHintId::ThisIsAnSdrHint)
+    {
+        const SdrHint* pSdrHint = static_cast<const SdrHint*>(&rHint);
+        switch (pSdrHint->GetKind())
+        {
+            case SdrHintKind::ModelCleared:
+                if (&rBroadcaster == mrSlideSorter.GetModel().GetDocument())
+                {   // rhbz#965646 stop listening to dying document
+                    EndListening(rBroadcaster);
+                    return;
+                }
+                break;
+            case SdrHintKind::PageOrderChange:
+                if (&rBroadcaster == mrSlideSorter.GetModel().GetDocument())
+                    HandleModelChange(pSdrHint->GetPage());
+                break;
+
+            default:
+                break;
+        }
+    }
+    else if (rHint.GetId() == SfxHintId::DocChanged)
+    {
+        mrController.CheckForMasterPageAssignment();
+        mrController.CheckForSlideTransitionAssignment();
+    }
+    else if (auto pViewShellHint = dynamic_cast<const ViewShellHint*>(&rHint))
+    {
+        switch (pViewShellHint->GetHintId())
+        {
+            case ViewShellHint::HINT_PAGE_RESIZE_START:
+                // Initiate a model change but do nothing (well, not much)
+                // until we are told that all slides have been resized.
+                mpModelChangeLock.reset(new SlideSorterController::ModelChangeLock(mrController),
+                                        o3tl::default_delete<SlideSorterController::ModelChangeLock>());
+                mrController.HandleModelChange();
+                break;
+
+            case ViewShellHint::HINT_PAGE_RESIZE_END:
+                // All slides have been resized.  The model has to be updated.
+                mpModelChangeLock.reset();
+                break;
+
+            case ViewShellHint::HINT_CHANGE_EDIT_MODE_START:
+                mrController.PrepareEditModeChange();
+                break;
+
+            case ViewShellHint::HINT_CHANGE_EDIT_MODE_END:
+                mrController.FinishEditModeChange();
+                break;
+
+            case ViewShellHint::HINT_COMPLEX_MODEL_CHANGE_START:
+                mpModelChangeLock.reset(new SlideSorterController::ModelChangeLock(mrController),
+                                        o3tl::default_delete<SlideSorterController::ModelChangeLock>());
+                break;
+
+            case ViewShellHint::HINT_COMPLEX_MODEL_CHANGE_END:
+                mpModelChangeLock.reset();
+                break;
+        }
+    }
+}
+
+IMPL_LINK(Listener, EventMultiplexerCallback, ::sd::tools::EventMultiplexerEvent&, rEvent, void)
+{
+    switch (rEvent.meEventId)
+    {
+        case EventMultiplexerEventId::MainViewRemoved:
+        {
+            if (mpBase != nullptr)
+            {
+                ViewShell* pMainViewShell = mpBase->GetMainViewShell().get();
+                if (pMainViewShell != nullptr)
+                    EndListening(*pMainViewShell);
+            }
+        }
+        break;
+
+        case EventMultiplexerEventId::MainViewAdded:
+            mbIsMainViewChangePending = true;
+            break;
+
+        case EventMultiplexerEventId::ConfigurationUpdated:
+            if (mbIsMainViewChangePending && mpBase != nullptr)
+            {
+                mbIsMainViewChangePending = false;
+                ViewShell* pMainViewShell = mpBase->GetMainViewShell().get();
+                if (pMainViewShell != nullptr
+                    && pMainViewShell!=mrSlideSorter.GetViewShell())
+                {
+                    StartListening (*pMainViewShell);
+                }
+            }
+            break;
+
+        case EventMultiplexerEventId::ControllerAttached:
+        {
+            ConnectToController();
+            //            mrController.GetPageSelector().GetCoreSelection();
+            UpdateEditMode();
+        }
+        break;
+
+        case EventMultiplexerEventId::ControllerDetached:
+            DisconnectFromController();
+            break;
+
+        case EventMultiplexerEventId::ShapeChanged:
+        case EventMultiplexerEventId::ShapeInserted:
+        case EventMultiplexerEventId::ShapeRemoved:
+            HandleShapeModification(static_cast<const SdrPage*>(rEvent.mpUserData));
+            break;
+
+        case EventMultiplexerEventId::EndTextEdit:
+            if (rEvent.mpUserData != nullptr)
+            {
+                const SdrObject* pObject = static_cast<const SdrObject*>(rEvent.mpUserData);
+                HandleShapeModification(pObject->getSdrPageFromSdrObject());
+            }
+            break;
+
+        default:
+            break;
+    }
+}
+
+//=====  lang::XEventListener  ================================================
+
+void SAL_CALL Listener::disposing (
+    const lang::EventObject& rEventObject)
+{
+    if ((mbListeningToDocument || mbListeningToUNODocument)
+        && mrSlideSorter.GetModel().GetDocument()!=nullptr
+        && rEventObject.Source
+           == mrSlideSorter.GetModel().GetDocument()->getUnoModel())
+    {
+        mbListeningToDocument = false;
+        mbListeningToUNODocument = false;
+    }
+    else if (mbListeningToController)
+    {
+        Reference<frame::XController> xController (mxControllerWeak);
+        if (rEventObject.Source == xController)
+        {
+            mbListeningToController = false;
+        }
+    }
+}
+
+//=====  document::XEventListener  ============================================
+
+void SAL_CALL Listener::notifyEvent (
+    const document::EventObject& )
+{
+}
+
+//=====  beans::XPropertySetListener  =========================================
+
+void SAL_CALL Listener::propertyChange (
+    const PropertyChangeEvent& rEvent)
+{
+    if (m_bDisposed)
+    {
+        throw lang::DisposedException ("SlideSorterController object has already been disposed",
+            static_cast<uno::XWeak*>(this));
+    }
+
+    if (rEvent.PropertyName == "CurrentPage")
+    {
+        Any aCurrentPage = rEvent.NewValue;
+        Reference<beans::XPropertySet> xPageSet (aCurrentPage, UNO_QUERY);
+        if (xPageSet.is())
+        {
+            try
+            {
+                Any aPageNumber = xPageSet->getPropertyValue ("Number");
+                sal_Int32 nCurrentPage = 0;
+                aPageNumber >>= nCurrentPage;
+                // The selection is already set but we call SelectPage()
+                // nevertheless in order to make the new current page the
+                // last recently selected page of the PageSelector.  This is
+                // used when making the selection visible.
+                mrController.GetCurrentSlideManager()->NotifyCurrentSlideChange(nCurrentPage-1);
+                mrController.GetPageSelector().SelectPage(nCurrentPage-1);
+            }
+            catch (beans::UnknownPropertyException&)
+            {
+                DBG_UNHANDLED_EXCEPTION("sd");
+            }
+            catch (lang::DisposedException&)
+            {
+                // Something is already disposed.  There is not much we can
+                // do, except not to crash.
+            }
+        }
+    }
+    else if (rEvent.PropertyName == "IsMasterPageMode")
+    {
+        bool bIsMasterPageMode = false;
+        rEvent.NewValue >>= bIsMasterPageMode;
+        mrController.ChangeEditMode (
+            bIsMasterPageMode ? EditMode::MasterPage : EditMode::Page);
+    }
+}
+
+//===== frame::XFrameActionListener  ==========================================
+
+void SAL_CALL Listener::frameAction (const frame::FrameActionEvent& rEvent)
+{
+    switch (rEvent.Action)
+    {
+        case frame::FrameAction_COMPONENT_DETACHING:
+            DisconnectFromController();
+            break;
+
+        case frame::FrameAction_COMPONENT_REATTACHED:
+        {
+            ConnectToController();
+            mrController.GetPageSelector().GetCoreSelection();
+            UpdateEditMode();
+        }
+        break;
+
+        default:
+            break;
+    }
+}
+
+//===== accessibility::XAccessibleEventListener  ==============================
+
+void SAL_CALL Listener::notifyEvent (
+    const AccessibleEventObject& )
+{
+}
+
+void Listener::disposing(std::unique_lock<std::mutex>&)
+{
+    ReleaseListeners();
+}
+
+void Listener::UpdateEditMode()
+{
+    // When there is a new controller then the edit mode may have changed at
+    // the same time.
+    Reference<frame::XController> xController (mxControllerWeak);
+    Reference<beans::XPropertySet> xSet (xController, UNO_QUERY);
+    bool bIsMasterPageMode = false;
+    if (xSet != nullptr)
+    {
+        try
+        {
+            Any aValue (xSet->getPropertyValue( "IsMasterPageMode" ));
+            aValue >>= bIsMasterPageMode;
+        }
+        catch (beans::UnknownPropertyException&)
+        {
+            // When the property is not supported then the master page mode
+            // is not supported, too.
+            bIsMasterPageMode = false;
+        }
+    }
+    mrController.ChangeEditMode (
+        bIsMasterPageMode ? EditMode::MasterPage : EditMode::Page);
+}
+
+void Listener::HandleModelChange (const SdrPage* pPage)
+{
+    // Notify model and selection observer about the page.  The return value
+    // of the model call acts as filter as to which events to pass to the
+    // selection observer.
+    if (mrSlideSorter.GetModel().NotifyPageEvent(pPage))
+    {
+        // The page of the hint belongs (or belonged) to the model.
+
+        // Tell the cache manager that the preview bitmaps for a deleted
+        // page can be removed from all caches.
+        if (pPage!=nullptr && ! pPage->IsInserted())
+            cache::PageCacheManager::Instance()->ReleasePreviewBitmap(pPage);
+
+        mrController.GetSelectionManager()->GetSelectionObserver()->NotifyPageEvent(pPage);
+    }
+
+    // Tell the controller about the model change only when the document is
+    // in a sane state, not just in the middle of a larger change.
+    SdDrawDocument* pDocument (mrSlideSorter.GetModel().GetDocument());
+    if (pDocument != nullptr
+        && pDocument->GetMasterSdPageCount(PageKind::Standard) == pDocument->GetMasterSdPageCount(PageKind::Notes))
+    {
+        // A model change can make updates of some text fields necessary
+        // (like page numbers and page count.)  Invalidate all previews in
+        // the cache to cope with this.  Doing this on demand would be a
+        // nice optimization.
+        cache::PageCacheManager::Instance()->InvalidateAllPreviewBitmaps(pDocument->getUnoModel());
+
+        mrController.HandleModelChange();
+    }
+}
+
+void Listener::HandleShapeModification (const SdrPage* pPage)
+{
+    if (pPage == nullptr)
+        return;
+
+    // Invalidate the preview of the page (in all slide sorters that display
+    // it.)
+    std::shared_ptr<cache::PageCacheManager> pCacheManager (cache::PageCacheManager::Instance());
+    if ( ! pCacheManager)
+        return;
+    SdDrawDocument* pDocument = mrSlideSorter.GetModel().GetDocument();
+    if (pDocument == nullptr)
+    {
+        OSL_ASSERT(pDocument!=nullptr);
+        return;
+    }
+    pCacheManager->InvalidatePreviewBitmap(pDocument->getUnoModel(), pPage);
+    mrSlideSorter.GetView().GetPreviewCache()->RequestPreviewBitmap(pPage);
+
+    // When the page is a master page then invalidate the previews of all
+    // pages that are linked to this master page.
+    if (!pPage->IsMasterPage())
+        return;
+
+    for (sal_uInt16 nIndex=0,nCount=pDocument->GetSdPageCount(PageKind::Standard);
+         nIndex<nCount;
+         ++nIndex)
+    {
+        const SdPage* pCandidate = pDocument->GetSdPage(nIndex, PageKind::Standard);
+        if (pCandidate!=nullptr && pCandidate->TRG_HasMasterPage())
+        {
+            if (&pCandidate->TRG_GetMasterPage() == pPage)
+                pCacheManager->InvalidatePreviewBitmap(pDocument->getUnoModel(), pCandidate);
+        }
+        else
+        {
+            OSL_ASSERT(pCandidate!=nullptr && pCandidate->TRG_HasMasterPage());
+        }
+    }
+}
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/controller/SlsListener.hxx b/sd/source/ui/slidesorter/controller/SlsListener.hxx
new file mode 100644
index 000000000..eff02cf19
--- /dev/null
+++ b/sd/source/ui/slidesorter/controller/SlsListener.hxx
@@ -0,0 +1,164 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <controller/SlideSorterController.hxx>
+#include <com/sun/star/document/XEventListener.hpp>
+#include <com/sun/star/beans/XPropertyChangeListener.hpp>
+#include <com/sun/star/accessibility/XAccessibleEventListener.hpp>
+#include <com/sun/star/frame/XFrameActionListener.hpp>
+#include <comphelper/compbase.hxx>
+#include <cppuhelper/weakref.hxx>
+
+#include <svl/lstner.hxx>
+#include <tools/link.hxx>
+#include <memory>
+
+class SdrPage;
+
+namespace sd {
+class ViewShellBase;
+}
+
+namespace sd::tools { class EventMultiplexerEvent; }
+namespace sd::slidesorter { class SlideSorter; }
+
+namespace sd::slidesorter::controller {
+
+typedef comphelper::WeakComponentImplHelper<
+    css::document::XEventListener,
+    css::beans::XPropertyChangeListener,
+    css::accessibility::XAccessibleEventListener,
+    css::frame::XFrameActionListener
+    > ListenerInterfaceBase;
+
+/** Listen for events of various types and sources and react to them.  This
+    class is a part of the controller.
+
+    When the view shell in the center pane is replaced by another the
+    associated controller is replaced as well.  Therefore we have to
+    register at the frame and on certain FrameActionEvents to stop listening
+    to the old controller and register as listener at the new one.
+*/
+class Listener
+    : public ListenerInterfaceBase,
+      public SfxListener
+{
+public:
+    explicit Listener (SlideSorter& rSlideSorter);
+    virtual ~Listener() override;
+
+    /** Connect to the current controller of the view shell as listener.
+        This method is called once during initialization and every time a
+        FrameActionEvent signals the current controller being exchanged.
+        When the connection is successful then the flag
+        mbListeningToController is set to <TRUE/>.
+    */
+    void ConnectToController();
+
+    /** Disconnect from the current controller of the view shell as
+        listener.  This method is called once during initialization and
+        every time a FrameActionEvent signals the current controller being
+        exchanged.  When this method terminates then mbListeningToController
+        is <FALSE/>.
+    */
+    void DisconnectFromController();
+
+    virtual void Notify (
+        SfxBroadcaster& rBroadcaster,
+        const SfxHint& rHint) override;
+
+    //=====  lang::XEventListener  ============================================
+    virtual void SAL_CALL
+        disposing (const css::lang::EventObject& rEventObject) override;
+
+    //=====  document::XEventListener  ========================================
+    virtual void SAL_CALL
+        notifyEvent (
+            const css::document::EventObject& rEventObject) override;
+
+    //=====  beans::XPropertySetListener  =====================================
+    virtual void SAL_CALL
+        propertyChange (
+            const css::beans::PropertyChangeEvent& rEvent) override;
+
+    //===== accessibility::XAccessibleEventListener  ==========================
+    virtual void SAL_CALL
+        notifyEvent (
+            const css::accessibility::AccessibleEventObject&
+            rEvent) override;
+
+    //===== frame::XFrameActionListener  ======================================
+    /** For certain actions the listener connects to a new controller of the
+        frame it is listening to.  This usually happens when the view shell
+        in the center pane is replaced by another view shell.
+    */
+    virtual void SAL_CALL
+        frameAction (const css::frame::FrameActionEvent& rEvent) override;
+
+    virtual void disposing(std::unique_lock<std::mutex>&) override;
+
+private:
+    SlideSorter& mrSlideSorter;
+    SlideSorterController& mrController;
+    ViewShellBase* mpBase;
+
+    /// Remember whether we are listening to the document.
+    bool mbListeningToDocument;
+    /// Remember whether we are listening to the UNO document.
+    bool mbListeningToUNODocument;
+    /// Remember whether we are listening to the UNO controller.
+    bool mbListeningToController;
+    /// Remember whether we are listening to the frame.
+    bool mbListeningToFrame;
+    bool mbIsMainViewChangePending;
+
+    css::uno::WeakReference< css::frame::XController> mxControllerWeak;
+    css::uno::WeakReference< css::frame::XFrame> mxFrameWeak;
+
+    /** This object is used to lock the model between some
+        events.  It is references counted in order to cope with events that
+        are expected but never sent.
+    */
+    std::shared_ptr<SlideSorterController::ModelChangeLock> mpModelChangeLock;
+
+    void ReleaseListeners();
+
+    /** Called when the edit mode has changed.  Update model accordingly.
+    */
+    void UpdateEditMode();
+
+    /** Handle a change in the order of slides or when the set of slides has
+        changed, i.e. a slide has been created.
+    */
+    void HandleModelChange (const SdrPage* pPage);
+
+    /** Handle a modification to a shape on the given page.  When this is a
+        regular page then update its preview.  When it is a master page then
+        additionally update the previews of all pages linked to it.
+    */
+    void HandleShapeModification (const SdrPage* pPage);
+
+    DECL_LINK(EventMultiplexerCallback, tools::EventMultiplexerEvent&, void);
+};
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/controller/SlsPageSelector.cxx b/sd/source/ui/slidesorter/controller/SlsPageSelector.cxx
new file mode 100644
index 000000000..21affcf2f
--- /dev/null
+++ b/sd/source/ui/slidesorter/controller/SlsPageSelector.cxx
@@ -0,0 +1,386 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <controller/SlsPageSelector.hxx>
+
+#include <SlideSorter.hxx>
+#include <controller/SlideSorterController.hxx>
+#include <controller/SlsSelectionManager.hxx>
+#include <controller/SlsCurrentSlideManager.hxx>
+#include <controller/SlsVisibleAreaManager.hxx>
+#include <model/SlsPageDescriptor.hxx>
+#include <model/SlsPageEnumerationProvider.hxx>
+#include <model/SlideSorterModel.hxx>
+#include <view/SlideSorterView.hxx>
+#include <osl/diagnose.h>
+
+#include <sdpage.hxx>
+#include <tools/debug.hxx>
+#include <memory>
+
+using namespace ::com::sun::star;
+using namespace ::com::sun::star::uno;
+using namespace ::sd::slidesorter::model;
+using namespace ::sd::slidesorter::view;
+
+namespace sd::slidesorter::controller {
+
+PageSelector::PageSelector (SlideSorter& rSlideSorter)
+    : mrModel(rSlideSorter.GetModel()),
+      mrSlideSorter(rSlideSorter),
+      mrController(mrSlideSorter.GetController()),
+      mnSelectedPageCount(0),
+      mnBroadcastDisableLevel(0),
+      mbSelectionChangeBroadcastPending(false),
+      mnUpdateLockCount(0),
+      mbIsUpdateCurrentPagePending(true)
+{
+    CountSelectedPages ();
+}
+
+void PageSelector::SelectAllPages()
+{
+    VisibleAreaManager::TemporaryDisabler aDisabler (mrSlideSorter);
+    PageSelector::UpdateLock aLock (*this);
+
+    int nPageCount = mrModel.GetPageCount();
+    for (int nPageIndex=0; nPageIndex<nPageCount; nPageIndex++)
+        SelectPage(nPageIndex);
+}
+
+void PageSelector::DeselectAllPages()
+{
+    VisibleAreaManager::TemporaryDisabler aDisabler (mrSlideSorter);
+    PageSelector::UpdateLock aLock (*this);
+
+    int nPageCount = mrModel.GetPageCount();
+    for (int nPageIndex=0; nPageIndex<nPageCount; nPageIndex++)
+        DeselectPage(nPageIndex);
+
+    DBG_ASSERT (mnSelectedPageCount==0,
+        "PageSelector::DeselectAllPages: the selected pages counter is not 0");
+    mnSelectedPageCount = 0;
+    mpSelectionAnchor.reset();
+}
+
+void PageSelector::GetCoreSelection()
+{
+    PageSelector::UpdateLock aLock (*this);
+
+    bool bSelectionHasChanged (true);
+    mnSelectedPageCount = 0;
+    model::PageEnumeration aAllPages (
+        model::PageEnumerationProvider::CreateAllPagesEnumeration(mrModel));
+    while (aAllPages.HasMoreElements())
+    {
+        model::SharedPageDescriptor pDescriptor (aAllPages.GetNextElement());
+        if (pDescriptor->GetCoreSelection())
+        {
+            mrSlideSorter.GetController().GetVisibleAreaManager().RequestVisible(pDescriptor);
+            mrSlideSorter.GetView().RequestRepaint(pDescriptor);
+            bSelectionHasChanged = true;
+        }
+
+        if (pDescriptor->HasState(PageDescriptor::ST_Selected))
+            mnSelectedPageCount++;
+    }
+
+    if (bSelectionHasChanged)
+    {
+        if (mnBroadcastDisableLevel > 0)
+            mbSelectionChangeBroadcastPending = true;
+        else
+            mrController.GetSelectionManager()->SelectionHasChanged();
+    }
+}
+
+void PageSelector::SetCoreSelection()
+{
+    model::PageEnumeration aAllPages (
+        model::PageEnumerationProvider::CreateAllPagesEnumeration(mrModel));
+    while (aAllPages.HasMoreElements())
+    {
+        model::SharedPageDescriptor pDescriptor (aAllPages.GetNextElement());
+        pDescriptor->SetCoreSelection();
+    }
+}
+
+void PageSelector::SelectPage (int nPageIndex)
+{
+    SharedPageDescriptor pDescriptor (mrModel.GetPageDescriptor(nPageIndex));
+    if (pDescriptor)
+        SelectPage(pDescriptor);
+}
+
+void PageSelector::SelectPage (const SdPage* pPage)
+{
+    const sal_Int32 nPageIndex (mrModel.GetIndex(pPage));
+    SharedPageDescriptor pDescriptor (mrModel.GetPageDescriptor(nPageIndex));
+    if (pDescriptor && pDescriptor->GetPage()==pPage)
+        SelectPage(pDescriptor);
+}
+
+void PageSelector::SelectPage (const SharedPageDescriptor& rpDescriptor)
+{
+    if (!rpDescriptor
+        || !mrSlideSorter.GetView().SetState(rpDescriptor, PageDescriptor::ST_Selected, true))
+        return;
+
+    ++mnSelectedPageCount;
+    mrSlideSorter.GetController().GetVisibleAreaManager().RequestVisible(rpDescriptor,true);
+    mrSlideSorter.GetView().RequestRepaint(rpDescriptor);
+
+    mpMostRecentlySelectedPage = rpDescriptor;
+    if (mpSelectionAnchor == nullptr)
+        mpSelectionAnchor = rpDescriptor;
+
+    if (mnBroadcastDisableLevel > 0)
+        mbSelectionChangeBroadcastPending = true;
+    else
+        mrController.GetSelectionManager()->SelectionHasChanged();
+    UpdateCurrentPage();
+
+    CheckConsistency();
+}
+
+void PageSelector::DeselectPage (int nPageIndex)
+{
+    model::SharedPageDescriptor pDescriptor (mrModel.GetPageDescriptor(nPageIndex));
+    if (pDescriptor)
+        DeselectPage(pDescriptor);
+}
+
+void PageSelector::DeselectPage (
+    const SharedPageDescriptor& rpDescriptor,
+    const bool bUpdateCurrentPage)
+{
+    if (!rpDescriptor
+        || !mrSlideSorter.GetView().SetState(rpDescriptor, PageDescriptor::ST_Selected, false))
+        return;
+
+    --mnSelectedPageCount;
+    mrSlideSorter.GetController().GetVisibleAreaManager().RequestVisible(rpDescriptor);
+    mrSlideSorter.GetView().RequestRepaint(rpDescriptor);
+    if (mpMostRecentlySelectedPage == rpDescriptor)
+        mpMostRecentlySelectedPage.reset();
+    if (mnBroadcastDisableLevel > 0)
+        mbSelectionChangeBroadcastPending = true;
+    else
+        mrController.GetSelectionManager()->SelectionHasChanged();
+    if (bUpdateCurrentPage)
+        UpdateCurrentPage();
+
+    CheckConsistency();
+}
+
+void PageSelector::CheckConsistency() const
+{
+    int nSelectionCount (0);
+    for (int nPageIndex=0,nPageCount=mrModel.GetPageCount(); nPageIndex<nPageCount; nPageIndex++)
+    {
+        SharedPageDescriptor pDescriptor (mrModel.GetPageDescriptor(nPageIndex));
+        assert(pDescriptor);
+        if (pDescriptor->HasState(PageDescriptor::ST_Selected))
+            ++nSelectionCount;
+    }
+    if (nSelectionCount!=mnSelectedPageCount)
+    {
+        // #i120020# The former call to assert(..) internally calls
+        // SlideSorterModel::GetPageDescriptor which will crash in this situation
+        // (only in non-pro code). All what is wanted there is to assert it (the
+        // error is already detected), so do this directly.
+        OSL_ENSURE(false, "PageSelector: Consistency error (!)");
+    }
+}
+
+bool PageSelector::IsPageSelected(int nPageIndex)
+{
+    SharedPageDescriptor pDescriptor (mrModel.GetPageDescriptor(nPageIndex));
+    if (pDescriptor)
+        return pDescriptor->HasState(PageDescriptor::ST_Selected);
+    else
+        return false;
+}
+
+bool PageSelector::IsPageVisible(int nPageIndex)
+{
+    SharedPageDescriptor pDescriptor (mrModel.GetPageDescriptor(nPageIndex));
+    if (pDescriptor)
+        return pDescriptor->HasState(PageDescriptor::ST_Visible);
+    else
+        return false;
+}
+
+int PageSelector::GetPageCount() const
+{
+    return mrModel.GetPageCount();
+}
+
+void PageSelector::CountSelectedPages()
+{
+    mnSelectedPageCount = 0;
+    model::PageEnumeration aSelectedPages (
+        model::PageEnumerationProvider::CreateSelectedPagesEnumeration(mrModel));
+    while (aSelectedPages.HasMoreElements())
+    {
+        mnSelectedPageCount++;
+        aSelectedPages.GetNextElement();
+    }
+}
+
+void PageSelector::EnableBroadcasting()
+{
+    if (mnBroadcastDisableLevel > 0)
+        mnBroadcastDisableLevel --;
+    if (mnBroadcastDisableLevel==0 && mbSelectionChangeBroadcastPending)
+    {
+        mrController.GetSelectionManager()->SelectionHasChanged();
+        mbSelectionChangeBroadcastPending = false;
+    }
+}
+
+void PageSelector::DisableBroadcasting()
+{
+    mnBroadcastDisableLevel ++;
+}
+
+std::shared_ptr<PageSelector::PageSelection> PageSelector::GetPageSelection() const
+{
+    auto pSelection = std::make_shared<PageSelection>();
+    pSelection->reserve(GetSelectedPageCount());
+
+    int nPageCount = GetPageCount();
+    for (int nIndex=0; nIndex<nPageCount; nIndex++)
+    {
+        SharedPageDescriptor pDescriptor (mrModel.GetPageDescriptor(nIndex));
+        if (pDescriptor && pDescriptor->HasState(PageDescriptor::ST_Selected))
+            pSelection->push_back(pDescriptor->GetPage());
+    }
+
+    return pSelection;
+}
+
+void PageSelector::SetPageSelection (
+    const std::shared_ptr<PageSelection>& rpSelection,
+    const bool bUpdateCurrentPage)
+{
+    for (const auto& rpPage : *rpSelection)
+        SelectPage(rpPage);
+    if (bUpdateCurrentPage)
+        UpdateCurrentPage();
+}
+
+void PageSelector::UpdateCurrentPage (const bool bUpdateOnlyWhenPending)
+{
+    if (mnUpdateLockCount > 0)
+    {
+        mbIsUpdateCurrentPagePending = true;
+        return;
+    }
+
+    if ( ! mbIsUpdateCurrentPagePending && bUpdateOnlyWhenPending)
+        return;
+
+    mbIsUpdateCurrentPagePending = false;
+
+    // Make the first selected page the current page.
+    SharedPageDescriptor pCurrentPageDescriptor;
+    const sal_Int32 nPageCount (GetPageCount());
+    for (sal_Int32 nIndex=0; nIndex<nPageCount; ++nIndex)
+    {
+        SharedPageDescriptor pDescriptor (mrModel.GetPageDescriptor(nIndex));
+        if ( ! pDescriptor)
+            continue;
+        if (pDescriptor->HasState(PageDescriptor::ST_Selected))
+        {
+            pCurrentPageDescriptor = pDescriptor;
+            break;
+        }
+    }
+
+    if (!pCurrentPageDescriptor)
+        return;
+
+    // Switching the current slide normally sets also the
+    // selection to just the new current slide.  To prevent that,
+    // we store (and at the end of this scope restore) the current
+    // selection.
+    std::shared_ptr<PageSelection> pSelection (GetPageSelection());
+
+    mrController.GetCurrentSlideManager()->SwitchCurrentSlide(pCurrentPageDescriptor);
+
+    // Restore the selection and prevent a recursive call to
+    // UpdateCurrentPage().
+    SetPageSelection(pSelection, false);
+}
+
+//===== PageSelector::UpdateLock ==============================================
+
+PageSelector::UpdateLock::UpdateLock (SlideSorter const & rSlideSorter)
+    : mpSelector(&rSlideSorter.GetController().GetPageSelector())
+{
+    ++mpSelector->mnUpdateLockCount;
+}
+
+PageSelector::UpdateLock::UpdateLock (PageSelector& rSelector)
+    : mpSelector(&rSelector)
+{
+    ++mpSelector->mnUpdateLockCount;
+}
+
+PageSelector::UpdateLock::~UpdateLock()
+{
+    Release();
+}
+
+void PageSelector::UpdateLock::Release()
+{
+    if (mpSelector != nullptr)
+    {
+        --mpSelector->mnUpdateLockCount;
+        OSL_ASSERT(mpSelector->mnUpdateLockCount >= 0);
+        if (mpSelector->mnUpdateLockCount == 0)
+            mpSelector->UpdateCurrentPage(true);
+
+        mpSelector = nullptr;
+    }
+}
+
+//===== PageSelector::BroadcastLock ==============================================
+
+PageSelector::BroadcastLock::BroadcastLock (SlideSorter const & rSlideSorter)
+    : mrSelector(rSlideSorter.GetController().GetPageSelector())
+{
+    mrSelector.DisableBroadcasting();
+}
+
+PageSelector::BroadcastLock::BroadcastLock (PageSelector& rSelector)
+    : mrSelector(rSelector)
+{
+    mrSelector.DisableBroadcasting();
+}
+
+PageSelector::BroadcastLock::~BroadcastLock()
+{
+    mrSelector.EnableBroadcasting();
+}
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/controller/SlsProperties.cxx b/sd/source/ui/slidesorter/controller/SlsProperties.cxx
new file mode 100644
index 000000000..f1152a373
--- /dev/null
+++ b/sd/source/ui/slidesorter/controller/SlsProperties.cxx
@@ -0,0 +1,106 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <controller/SlsProperties.hxx>
+#include <vcl/svapp.hxx>
+#include <vcl/settings.hxx>
+
+namespace sd::slidesorter::controller {
+
+Properties::Properties()
+    : mbIsHighlightCurrentSlide(false),
+      mbIsShowSelection(true),
+      mbIsShowFocus(true),
+      mbIsCenterSelection(false),
+      mbIsSmoothSelectionScrolling(true),
+      mbIsSuspendPreviewUpdatesDuringFullScreenPresentation(true),
+      maBackgroundColor(Application::GetSettings().GetStyleSettings().GetWindowColor()),
+      maTextColor(Application::GetSettings().GetStyleSettings().GetActiveTextColor()),
+      maSelectionColor(Application::GetSettings().GetStyleSettings().GetHighlightColor()),
+      maHighlightColor(Application::GetSettings().GetStyleSettings().GetMenuHighlightColor()),
+      mbIsUIReadOnly(false)
+{
+}
+
+void Properties::HandleDataChangeEvent()
+{
+    maBackgroundColor = Application::GetSettings().GetStyleSettings().GetWindowColor();
+    maTextColor = Application::GetSettings().GetStyleSettings().GetActiveTextColor();
+    maSelectionColor = Application::GetSettings().GetStyleSettings().GetHighlightColor();
+    maHighlightColor = Application::GetSettings().GetStyleSettings().GetMenuHighlightColor();
+}
+
+void Properties::SetHighlightCurrentSlide (const bool bIsHighlightCurrentSlide)
+{
+    mbIsHighlightCurrentSlide = bIsHighlightCurrentSlide;
+}
+
+void Properties::SetShowSelection (const bool bIsShowSelection)
+{
+    mbIsShowSelection = bIsShowSelection;
+}
+
+void Properties::SetShowFocus (const bool bIsShowFocus)
+{
+    mbIsShowFocus = bIsShowFocus;
+}
+
+void Properties::SetCenterSelection (const bool bIsCenterSelection)
+{
+    mbIsCenterSelection = bIsCenterSelection;
+}
+
+void Properties::SetSmoothSelectionScrolling (const bool bIsSmoothSelectionScrolling)
+{
+    mbIsSmoothSelectionScrolling = bIsSmoothSelectionScrolling;
+}
+
+void Properties::SetSuspendPreviewUpdatesDuringFullScreenPresentation (const bool bFlag)
+{
+    mbIsSuspendPreviewUpdatesDuringFullScreenPresentation = bFlag;
+}
+
+void Properties::SetBackgroundColor (const Color& rColor)
+{
+    maBackgroundColor = rColor;
+}
+
+void Properties::SetTextColor (const Color& rColor)
+{
+    maTextColor = rColor;
+}
+
+void Properties::SetSelectionColor (const Color& rColor)
+{
+    maSelectionColor = rColor;
+}
+
+void Properties::SetHighlightColor (const Color& rColor)
+{
+    maHighlightColor = rColor;
+}
+
+void Properties::SetUIReadOnly (const bool bIsUIReadOnly)
+{
+    mbIsUIReadOnly = bIsUIReadOnly;
+}
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/controller/SlsScrollBarManager.cxx b/sd/source/ui/slidesorter/controller/SlsScrollBarManager.cxx
new file mode 100644
index 000000000..83192414f
--- /dev/null
+++ b/sd/source/ui/slidesorter/controller/SlsScrollBarManager.cxx
@@ -0,0 +1,608 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <controller/SlsScrollBarManager.hxx>
+
+#include <SlideSorter.hxx>
+#include <ViewShell.hxx>
+#include <controller/SlideSorterController.hxx>
+#include <controller/SlsVisibleAreaManager.hxx>
+#include <model/SlideSorterModel.hxx>
+#include <model/SlsPageDescriptor.hxx>
+#include <view/SlideSorterView.hxx>
+#include <view/SlsLayouter.hxx>
+#include <Window.hxx>
+#include <sdpage.hxx>
+#include <osl/diagnose.h>
+
+#include <vcl/scrbar.hxx>
+
+namespace sd::slidesorter::controller {
+
+constexpr double gnHorizontalScrollFactor(0.15);
+constexpr double gnVerticalScrollFactor(0.25);
+
+ScrollBarManager::ScrollBarManager (SlideSorter& rSlideSorter)
+    : mrSlideSorter(rSlideSorter),
+      mpHorizontalScrollBar(mrSlideSorter.GetHorizontalScrollBar()),
+      mpVerticalScrollBar(mrSlideSorter.GetVerticalScrollBar()),
+      mnHorizontalPosition (0),
+      mnVerticalPosition (0),
+      maScrollBorder (20,20),
+      mpScrollBarFiller(mrSlideSorter.GetScrollBarFiller()),
+      maAutoScrollTimer("sd ScrollBarManager maAutoScrollTimer"),
+      maAutoScrollOffset(0,0),
+      mbIsAutoScrollActive(false),
+      mpContentWindow(mrSlideSorter.GetContentWindow())
+{
+    // Hide the scroll bars by default to prevent display errors while
+    // switching between view shells:  In the short time between initiating
+    // such a switch and the final rearrangement of UI controls the scroll
+    // bars and the filler where displayed in the upper left corner of the
+    // ViewTabBar.
+    mpHorizontalScrollBar->Hide();
+    mpVerticalScrollBar->Hide();
+    mpScrollBarFiller->Hide();
+
+    maAutoScrollTimer.SetTimeout(25);
+    maAutoScrollTimer.SetInvokeHandler (
+        LINK(this, ScrollBarManager, AutoScrollTimeoutHandler));
+}
+
+ScrollBarManager::~ScrollBarManager()
+{
+}
+
+void ScrollBarManager::Connect()
+{
+    if (mpVerticalScrollBar != nullptr)
+    {
+        mpVerticalScrollBar->SetScrollHdl (
+            LINK(this, ScrollBarManager, VerticalScrollBarHandler));
+    }
+    if (mpHorizontalScrollBar != nullptr)
+    {
+        mpHorizontalScrollBar->SetScrollHdl(
+            LINK(this, ScrollBarManager, HorizontalScrollBarHandler));
+    }
+}
+
+void ScrollBarManager::Disconnect()
+{
+    if (mpVerticalScrollBar != nullptr)
+    {
+        mpVerticalScrollBar->SetScrollHdl( Link<ScrollBar*,void>() );
+    }
+    if (mpHorizontalScrollBar != nullptr)
+    {
+        mpHorizontalScrollBar->SetScrollHdl( Link<ScrollBar*,void>() );
+    }
+}
+
+/** Placing the scroll bars is an iterative process.  The visibility of one
+    scroll bar affects the remaining size and thus may lead to the other
+    scroll bar becoming visible.
+
+    First we determine the visibility of the horizontal scroll bar.  After
+    that we do the same for the vertical scroll bar.  To have an initial
+    value for the required size we call the layouter before that.  When one
+    of the two scroll bars is made visible then the size of the browser
+    window changes and a second call to the layouter becomes necessary.
+    That call is made anyway after this method returns.
+*/
+::tools::Rectangle ScrollBarManager::PlaceScrollBars (
+    const ::tools::Rectangle& rAvailableArea,
+    const bool bIsHorizontalScrollBarAllowed,
+    const bool bIsVerticalScrollBarAllowed)
+{
+    ::tools::Rectangle aRemainingSpace (DetermineScrollBarVisibilities(
+        rAvailableArea,
+        bIsHorizontalScrollBarAllowed,
+        bIsVerticalScrollBarAllowed));
+
+    if (mpHorizontalScrollBar!=nullptr && mpHorizontalScrollBar->IsVisible())
+        PlaceHorizontalScrollBar (rAvailableArea);
+
+    if (mpVerticalScrollBar!=nullptr && mpVerticalScrollBar->IsVisible())
+        PlaceVerticalScrollBar (rAvailableArea);
+
+    if (mpScrollBarFiller!=nullptr && mpScrollBarFiller->IsVisible())
+        PlaceFiller (rAvailableArea);
+
+    return aRemainingSpace;
+}
+
+void ScrollBarManager::PlaceHorizontalScrollBar (const ::tools::Rectangle& aAvailableArea)
+{
+    // Save the current relative position.
+    mnHorizontalPosition = double(mpHorizontalScrollBar->GetThumbPos())
+        / double(mpHorizontalScrollBar->GetRange().Len());
+
+    // Place the scroll bar.
+    Size aScrollBarSize (mpHorizontalScrollBar->GetSizePixel());
+    mpHorizontalScrollBar->SetPosSizePixel (
+        Point(aAvailableArea.Left(),
+            aAvailableArea.Bottom()-aScrollBarSize.Height()+1),
+        Size (aAvailableArea.GetWidth() - GetVerticalScrollBarWidth(),
+            aScrollBarSize.Height()));
+
+    // Restore the relative position.
+    mpHorizontalScrollBar->SetThumbPos(
+        static_cast<::tools::Long>(0.5 + mnHorizontalPosition * mpHorizontalScrollBar->GetRange().Len()));
+}
+
+void ScrollBarManager::PlaceVerticalScrollBar (const ::tools::Rectangle& aArea)
+{
+    const sal_Int32 nThumbPosition (mpVerticalScrollBar->GetThumbPos());
+
+    // Place the scroll bar.
+    Size aScrollBarSize (mpVerticalScrollBar->GetSizePixel());
+    Point aPosition (aArea.Right()-aScrollBarSize.Width()+1, aArea.Top());
+    Size aSize (aScrollBarSize.Width(), aArea.GetHeight() - GetHorizontalScrollBarHeight());
+    mpVerticalScrollBar->SetPosSizePixel(aPosition, aSize);
+
+    // Restore the position.
+    mpVerticalScrollBar->SetThumbPos(static_cast<::tools::Long>(nThumbPosition));
+    mnVerticalPosition = nThumbPosition / double(mpVerticalScrollBar->GetRange().Len());
+}
+
+void ScrollBarManager::PlaceFiller (const ::tools::Rectangle& aArea)
+{
+    mpScrollBarFiller->SetPosSizePixel(
+        Point(
+            aArea.Right()-mpVerticalScrollBar->GetSizePixel().Width()+1,
+            aArea.Bottom()-mpHorizontalScrollBar->GetSizePixel().Height()+1),
+        Size (
+            mpVerticalScrollBar->GetSizePixel().Width(),
+            mpHorizontalScrollBar->GetSizePixel().Height()));
+}
+
+void ScrollBarManager::UpdateScrollBars(bool bUseScrolling)
+{
+    ::tools::Rectangle aModelArea (mrSlideSorter.GetView().GetModelArea());
+    sd::Window *pWindow (mrSlideSorter.GetContentWindow().get());
+    Size aWindowModelSize (pWindow->PixelToLogic(pWindow->GetSizePixel()));
+
+    // The horizontal scroll bar is only shown when the window is
+    // horizontally smaller than the view.
+    if (mpHorizontalScrollBar != nullptr && mpHorizontalScrollBar->IsVisible())
+    {
+        mpHorizontalScrollBar->Show();
+        mpHorizontalScrollBar->SetRange (
+            Range(aModelArea.Left(), aModelArea.Right()));
+        mnHorizontalPosition =
+                double(mpHorizontalScrollBar->GetThumbPos())
+                / double(mpHorizontalScrollBar->GetRange().Len());
+
+        mpHorizontalScrollBar->SetVisibleSize (aWindowModelSize.Width());
+
+        const ::tools::Long nWidth (mpContentWindow->PixelToLogic(
+            mpContentWindow->GetSizePixel()).Width());
+        // Make the line size about 10% of the visible width.
+        mpHorizontalScrollBar->SetLineSize (nWidth / 10);
+        // Make the page size about 90% of the visible width.
+        mpHorizontalScrollBar->SetPageSize ((nWidth * 9) / 10);
+    }
+    else
+    {
+        mnHorizontalPosition = 0;
+    }
+
+    // The vertical scroll bar is always shown.
+    if (mpVerticalScrollBar != nullptr && mpVerticalScrollBar->IsVisible())
+    {
+        mpVerticalScrollBar->SetRange (
+            Range(aModelArea.Top(), aModelArea.Bottom()));
+        mnVerticalPosition =
+                double(mpVerticalScrollBar->GetThumbPos())
+                / double(mpVerticalScrollBar->GetRange().Len());
+
+        mpVerticalScrollBar->SetVisibleSize (aWindowModelSize.Height());
+
+        const ::tools::Long nHeight (mpContentWindow->PixelToLogic(
+            mpContentWindow->GetSizePixel()).Height());
+        // Make the line size about 10% of the visible height.
+        mpVerticalScrollBar->SetLineSize (nHeight / 10);
+        // Make the page size about 90% of the visible height.
+        mpVerticalScrollBar->SetPageSize ((nHeight * 9) / 10);
+    }
+    else
+    {
+        mnVerticalPosition = 0;
+    }
+
+    double nEps (::std::numeric_limits<double>::epsilon());
+    if (fabs(mnHorizontalPosition-pWindow->GetVisibleX()) > nEps
+        || fabs(mnVerticalPosition-pWindow->GetVisibleY()) > nEps)
+    {
+        mrSlideSorter.GetView().InvalidatePageObjectVisibilities();
+        if (bUseScrolling)
+            pWindow->SetVisibleXY(mnHorizontalPosition, mnVerticalPosition);
+        else
+            SetWindowOrigin(mnHorizontalPosition, mnVerticalPosition);
+    }
+}
+
+IMPL_LINK(ScrollBarManager, VerticalScrollBarHandler, ScrollBar*, pScrollBar, void)
+{
+    if (pScrollBar!=nullptr
+        && pScrollBar==mpVerticalScrollBar.get()
+        && pScrollBar->IsVisible()
+        && mrSlideSorter.GetContentWindow())
+    {
+        double nRelativePosition = double(pScrollBar->GetThumbPos())
+            / double(pScrollBar->GetRange().Len());
+        mrSlideSorter.GetView().InvalidatePageObjectVisibilities();
+        mrSlideSorter.GetContentWindow()->SetVisibleXY(-1, nRelativePosition);
+        mrSlideSorter.GetController().GetVisibleAreaManager().DeactivateCurrentSlideTracking();
+    }
+}
+
+IMPL_LINK(ScrollBarManager, HorizontalScrollBarHandler, ScrollBar*, pScrollBar, void)
+{
+    if (pScrollBar!=nullptr
+        && pScrollBar==mpHorizontalScrollBar.get()
+        && pScrollBar->IsVisible()
+        && mrSlideSorter.GetContentWindow())
+    {
+        double nRelativePosition = double(pScrollBar->GetThumbPos())
+            / double(pScrollBar->GetRange().Len());
+        mrSlideSorter.GetView().InvalidatePageObjectVisibilities();
+        mrSlideSorter.GetContentWindow()->SetVisibleXY(nRelativePosition, -1);
+        mrSlideSorter.GetController().GetVisibleAreaManager().DeactivateCurrentSlideTracking();
+    }
+}
+
+void ScrollBarManager::SetWindowOrigin (
+    double nHorizontalPosition,
+    double nVerticalPosition)
+{
+    mnHorizontalPosition = nHorizontalPosition;
+    mnVerticalPosition = nVerticalPosition;
+
+    sd::Window *pWindow (mrSlideSorter.GetContentWindow().get());
+    Size aViewSize (pWindow->GetViewSize());
+    Point aOrigin (
+        static_cast<::tools::Long>(mnHorizontalPosition * aViewSize.Width()),
+        static_cast<::tools::Long>(mnVerticalPosition * aViewSize.Height()));
+
+    pWindow->SetWinViewPos (aOrigin);
+    pWindow->UpdateMapMode ();
+    pWindow->Invalidate ();
+}
+
+/** Determining the visibility of the scroll bars is quite complicated.  The
+    visibility of one influences that of the other because showing a scroll
+    bar makes the available space smaller and may lead to the need of
+    displaying the other.
+    To solve this we test all four combinations of showing or hiding each
+    scroll bar and use the best one.  The best one is that combination that
+    a) shows the least number of scroll bars with preference of showing the
+    vertical over showing the horizontal and
+    b) when not showing a scroll bar the area used by the page objects fits
+    into the available area in the scroll bars orientation.
+*/
+::tools::Rectangle ScrollBarManager::DetermineScrollBarVisibilities (
+    const ::tools::Rectangle& rAvailableArea,
+    const bool bIsHorizontalScrollBarAllowed,
+    const bool bIsVerticalScrollBarAllowed)
+{
+    // Test which combination of scroll bars is the best.
+    bool bShowHorizontal = false;
+    bool bShowVertical = false;
+    if (mrSlideSorter.GetModel().GetPageCount() == 0)
+    {
+        // No pages => no scroll bars.
+    }
+    else if (TestScrollBarVisibilities(false, false, rAvailableArea))
+    {
+        // Nothing to be done.
+    }
+    else if (bIsHorizontalScrollBarAllowed
+        && TestScrollBarVisibilities(true, false, rAvailableArea))
+    {
+        bShowHorizontal = true;
+    }
+    else if (bIsVerticalScrollBarAllowed
+        && TestScrollBarVisibilities(false, true, rAvailableArea))
+    {
+        bShowVertical = true;
+    }
+    else
+    {
+        bShowHorizontal = true;
+        bShowVertical = true;
+    }
+
+    // Make the visibility of the scroll bars permanent.
+    mpVerticalScrollBar->Show(bShowVertical);
+    mpHorizontalScrollBar->Show(bShowHorizontal);
+    mpScrollBarFiller->Show(bShowVertical && bShowHorizontal);
+
+    // Adapt the remaining space accordingly.
+    ::tools::Rectangle aRemainingSpace (rAvailableArea);
+    if (bShowVertical)
+        aRemainingSpace.AdjustRight( -(mpVerticalScrollBar->GetSizePixel().Width()) );
+    if (bShowHorizontal)
+        aRemainingSpace.AdjustBottom( -(mpHorizontalScrollBar->GetSizePixel().Height()) );
+
+    return aRemainingSpace;
+}
+
+bool ScrollBarManager::TestScrollBarVisibilities (
+    bool bHorizontalScrollBarVisible,
+    bool bVerticalScrollBarVisible,
+    const ::tools::Rectangle& rAvailableArea)
+{
+    model::SlideSorterModel& rModel (mrSlideSorter.GetModel());
+
+    // Adapt the available size by subtracting the sizes of the scroll bars
+    // visible in this combination.
+    Size aBrowserSize (rAvailableArea.GetSize());
+    if (bHorizontalScrollBarVisible)
+        aBrowserSize.AdjustHeight( -(mpHorizontalScrollBar->GetSizePixel().Height()) );
+    if (bVerticalScrollBarVisible)
+        aBrowserSize.AdjustWidth( -(mpVerticalScrollBar->GetSizePixel().Width()) );
+
+    // Tell the view to rearrange its page objects and check whether the
+    // page objects can be shown without clipping.
+    bool bRearrangeSuccess (mrSlideSorter.GetView().GetLayouter().Rearrange (
+        mrSlideSorter.GetView().GetOrientation(),
+        aBrowserSize,
+        rModel.GetPageDescriptor(0)->GetPage()->GetSize(),
+        rModel.GetPageCount()));
+
+    if (bRearrangeSuccess)
+    {
+        Size aPageSize = mrSlideSorter.GetView().GetLayouter().GetTotalBoundingBox().GetSize();
+        Size aWindowModelSize = mpContentWindow->PixelToLogic(aBrowserSize);
+
+        // The content may be clipped, i.e. not fully visible, in one
+        // direction only when the scroll bar is visible in that direction.
+        if (aPageSize.Width() > aWindowModelSize.Width())
+            if ( ! bHorizontalScrollBarVisible)
+                return false;
+        if (aPageSize.Height() > aWindowModelSize.Height())
+            if ( ! bVerticalScrollBarVisible)
+                return false;
+
+        return true;
+    }
+    else
+        return false;
+}
+
+void ScrollBarManager::SetTopLeft(const Point& rNewTopLeft)
+{
+    if (( ! mpVerticalScrollBar
+            || mpVerticalScrollBar->GetThumbPos() == rNewTopLeft.Y())
+        && ( ! mpHorizontalScrollBar
+            || mpHorizontalScrollBar->GetThumbPos() == rNewTopLeft.X()))
+        return;
+
+    // Flush pending repaints before scrolling to avoid temporary artifacts.
+    mrSlideSorter.GetContentWindow()->PaintImmediately();
+
+    if (mpVerticalScrollBar)
+    {
+        mpVerticalScrollBar->SetThumbPos(rNewTopLeft.Y());
+        mnVerticalPosition = rNewTopLeft.Y() / double(mpVerticalScrollBar->GetRange().Len());
+    }
+    if (mpHorizontalScrollBar)
+    {
+        mpHorizontalScrollBar->SetThumbPos(rNewTopLeft.X());
+        mnHorizontalPosition = rNewTopLeft.X() / double(mpHorizontalScrollBar->GetRange().Len());
+    }
+
+    mrSlideSorter.GetContentWindow()->SetVisibleXY(mnHorizontalPosition, mnVerticalPosition);
+    mrSlideSorter.GetView().InvalidatePageObjectVisibilities();
+}
+
+int ScrollBarManager::GetVerticalScrollBarWidth() const
+{
+    if (mpVerticalScrollBar != nullptr && mpVerticalScrollBar->IsVisible())
+        return mpVerticalScrollBar->GetSizePixel().Width();
+    else
+        return 0;
+}
+
+int ScrollBarManager::GetHorizontalScrollBarHeight() const
+{
+    if (mpHorizontalScrollBar != nullptr && mpHorizontalScrollBar->IsVisible())
+        return mpHorizontalScrollBar->GetSizePixel().Height();
+    else
+        return 0;
+}
+
+void ScrollBarManager::CalcAutoScrollOffset (const Point& rMouseWindowPosition)
+{
+    sd::Window *pWindow (mrSlideSorter.GetContentWindow().get());
+
+    int nDx = 0;
+    int nDy = 0;
+
+    Size aWindowSize = pWindow->GetOutputSizePixel();
+    ::tools::Rectangle aWindowArea (pWindow->GetPosPixel(), aWindowSize);
+    ::tools::Rectangle aViewPixelArea (
+        pWindow->LogicToPixel(mrSlideSorter.GetView().GetModelArea()));
+
+    if (aWindowSize.Width() > maScrollBorder.Width() * 3
+        && mpHorizontalScrollBar != nullptr
+        && mpHorizontalScrollBar->IsVisible())
+    {
+        if (rMouseWindowPosition.X() < maScrollBorder.Width()
+            && aWindowArea.Left() > aViewPixelArea.Left())
+        {
+            nDx = -1 + static_cast<int>(gnHorizontalScrollFactor
+                * (rMouseWindowPosition.X() - maScrollBorder.Width()));
+        }
+
+        if (rMouseWindowPosition.X() >= (aWindowSize.Width() - maScrollBorder.Width())
+            && aWindowArea.Right() < aViewPixelArea.Right())
+        {
+            nDx = 1 + static_cast<int>(gnHorizontalScrollFactor
+                * (rMouseWindowPosition.X() - aWindowSize.Width()
+                    + maScrollBorder.Width()));
+        }
+    }
+
+    if (aWindowSize.Height() > maScrollBorder.Height() * 3
+        && aWindowSize.Height() < aViewPixelArea.GetHeight())
+    {
+        if (rMouseWindowPosition.Y() < maScrollBorder.Height()
+            && aWindowArea.Top() > aViewPixelArea.Top())
+        {
+            nDy = -1 + static_cast<int>(gnVerticalScrollFactor
+                * (rMouseWindowPosition.Y() - maScrollBorder.Height()));
+        }
+
+        if (rMouseWindowPosition.Y() >= (aWindowSize.Height() - maScrollBorder.Height())
+            && aWindowArea.Bottom() < aViewPixelArea.Bottom())
+        {
+            nDy = 1 + static_cast<int>(gnVerticalScrollFactor
+                * (rMouseWindowPosition.Y() - aWindowSize.Height()
+                    + maScrollBorder.Height()));
+        }
+    }
+
+    maAutoScrollOffset = Size(nDx,nDy);
+}
+
+bool ScrollBarManager::AutoScroll (
+    const Point& rMouseWindowPosition,
+    const ::std::function<void ()>& rAutoScrollFunctor)
+{
+    maAutoScrollFunctor = rAutoScrollFunctor;
+    CalcAutoScrollOffset(rMouseWindowPosition);
+    bool bResult (true);
+    if ( ! mbIsAutoScrollActive)
+        bResult = RepeatAutoScroll();
+
+    return bResult;
+}
+
+void ScrollBarManager::StopAutoScroll()
+{
+    maAutoScrollTimer.Stop();
+    mbIsAutoScrollActive = false;
+}
+
+bool ScrollBarManager::RepeatAutoScroll()
+{
+    if (maAutoScrollOffset != Size(0,0))
+    {
+        if (mrSlideSorter.GetViewShell() != nullptr)
+        {
+            mrSlideSorter.GetViewShell()->Scroll(
+                maAutoScrollOffset.Width(),
+                maAutoScrollOffset.Height());
+            mrSlideSorter.GetView().InvalidatePageObjectVisibilities();
+
+            if (maAutoScrollFunctor)
+                maAutoScrollFunctor();
+
+            mbIsAutoScrollActive = true;
+            maAutoScrollTimer.Start();
+
+            return true;
+        }
+    }
+
+    clearAutoScrollFunctor();
+    mbIsAutoScrollActive = false;
+    return false;
+}
+
+void ScrollBarManager::clearAutoScrollFunctor()
+{
+    maAutoScrollFunctor = ::std::function<void ()>();
+}
+
+IMPL_LINK_NOARG(ScrollBarManager, AutoScrollTimeoutHandler, Timer *, void)
+{
+    RepeatAutoScroll();
+}
+
+void ScrollBarManager::Scroll(
+    const Orientation eOrientation,
+    const sal_Int32 nDistance)
+{
+    bool bIsVertical (false);
+    switch (eOrientation)
+    {
+        case Orientation_Horizontal: bIsVertical = false; break;
+        case Orientation_Vertical: bIsVertical = true; break;
+        default:
+            OSL_ASSERT(eOrientation==Orientation_Horizontal || eOrientation==Orientation_Vertical);
+            return;
+    }
+
+    Point aNewTopLeft (
+        mpHorizontalScrollBar ? mpHorizontalScrollBar->GetThumbPos() : 0,
+        mpVerticalScrollBar ? mpVerticalScrollBar->GetThumbPos() : 0);
+
+    view::Layouter& rLayouter (mrSlideSorter.GetView().GetLayouter());
+
+    // Calculate estimate of new location.
+    if (bIsVertical)
+        aNewTopLeft.AdjustY(nDistance * rLayouter.GetPageObjectSize().Height() );
+    else
+        aNewTopLeft.AdjustX(nDistance * rLayouter.GetPageObjectSize().Width() );
+
+    // Adapt location to show whole slides.
+    if (bIsVertical)
+        if (nDistance > 0)
+        {
+            const sal_Int32 nIndex (rLayouter.GetIndexAtPoint(
+                Point(aNewTopLeft.X(), aNewTopLeft.Y()+mpVerticalScrollBar->GetVisibleSize()),
+                true));
+            aNewTopLeft.setY( rLayouter.GetPageObjectBox(nIndex,true).Bottom()
+                - mpVerticalScrollBar->GetVisibleSize() );
+        }
+        else
+        {
+            const sal_Int32 nIndex (rLayouter.GetIndexAtPoint(
+                Point(aNewTopLeft.X(), aNewTopLeft.Y()),
+                true));
+            aNewTopLeft.setY( rLayouter.GetPageObjectBox(nIndex,true).Top() );
+        }
+    else
+        if (nDistance > 0)
+        {
+            const sal_Int32 nIndex (rLayouter.GetIndexAtPoint(
+                Point(aNewTopLeft.X()+mpVerticalScrollBar->GetVisibleSize(), aNewTopLeft.Y()),
+                true));
+            aNewTopLeft.setX( rLayouter.GetPageObjectBox(nIndex,true).Right()
+                - mpVerticalScrollBar->GetVisibleSize() );
+        }
+        else
+        {
+            const sal_Int32 nIndex (rLayouter.GetIndexAtPoint(
+                Point(aNewTopLeft.X(), aNewTopLeft.Y()),
+                    true));
+            aNewTopLeft.setX( rLayouter.GetPageObjectBox(nIndex,true).Left() );
+        }
+
+    mrSlideSorter.GetController().GetVisibleAreaManager().DeactivateCurrentSlideTracking();
+    SetTopLeft(aNewTopLeft);
+}
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/controller/SlsSelectionFunction.cxx b/sd/source/ui/slidesorter/controller/SlsSelectionFunction.cxx
new file mode 100644
index 000000000..c710a4c1b
--- /dev/null
+++ b/sd/source/ui/slidesorter/controller/SlsSelectionFunction.cxx
@@ -0,0 +1,1485 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <memory>
+#include <sal/config.h>
+
+#include <controller/SlsSelectionFunction.hxx>
+
+#include <SlideSorter.hxx>
+#include <SlideSorterViewShell.hxx>
+#include "SlsDragAndDropContext.hxx"
+#include <controller/SlideSorterController.hxx>
+#include <controller/SlsPageSelector.hxx>
+#include <controller/SlsFocusManager.hxx>
+#include <controller/SlsScrollBarManager.hxx>
+#include <controller/SlsClipboard.hxx>
+#include <controller/SlsCurrentSlideManager.hxx>
+#include <controller/SlsInsertionIndicatorHandler.hxx>
+#include <controller/SlsSelectionManager.hxx>
+#include <controller/SlsProperties.hxx>
+#include <controller/SlsVisibleAreaManager.hxx>
+#include <model/SlideSorterModel.hxx>
+#include <model/SlsPageDescriptor.hxx>
+#include <model/SlsPageEnumerationProvider.hxx>
+#include <view/SlideSorterView.hxx>
+#include <view/SlsLayouter.hxx>
+#include <framework/FrameworkHelper.hxx>
+#include <osl/diagnose.h>
+#include <Window.hxx>
+#include <sdpage.hxx>
+#include <drawdoc.hxx>
+#include <sdxfer.hxx>
+#include <ViewShell.hxx>
+#include <FrameView.hxx>
+#include <app.hrc>
+#include <o3tl/deleter.hxx>
+#include <sfx2/dispatch.hxx>
+#include <vcl/ptrstyle.hxx>
+#include <optional>
+#include <sdmod.hxx>
+
+namespace {
+const sal_uInt32 SINGLE_CLICK             (0x00000001);
+const sal_uInt32 DOUBLE_CLICK             (0x00000002);
+const sal_uInt32 LEFT_BUTTON              (0x00000010);
+const sal_uInt32 RIGHT_BUTTON             (0x00000020);
+const sal_uInt32 MIDDLE_BUTTON            (0x00000040);
+const sal_uInt32 BUTTON_DOWN              (0x00000100);
+const sal_uInt32 BUTTON_UP                (0x00000200);
+const sal_uInt32 MOUSE_MOTION             (0x00000400);
+const sal_uInt32 MOUSE_DRAG               (0x00000800);
+// The rest leaves the lower 16 bit untouched so that it can be used with
+// key codes.
+const sal_uInt32 OVER_SELECTED_PAGE       (0x00010000);
+const sal_uInt32 OVER_UNSELECTED_PAGE     (0x00020000);
+const sal_uInt32 SHIFT_MODIFIER           (0x00200000);
+const sal_uInt32 CONTROL_MODIFIER         (0x00400000);
+
+// Some absent events are defined so they can be expressed explicitly.
+const sal_uInt32 NO_MODIFIER              (0x00000000);
+const sal_uInt32 NOT_OVER_PAGE            (0x00000000);
+
+// Masks
+const sal_uInt32 MODIFIER_MASK            (SHIFT_MODIFIER | CONTROL_MODIFIER);
+
+} // end of anonymous namespace
+
+// Define some macros to make the following switch statement more readable.
+#define ANY_MODIFIER(code)                  \
+         code|NO_MODIFIER:                  \
+    case code|SHIFT_MODIFIER:               \
+    case code|CONTROL_MODIFIER
+
+namespace sd::slidesorter::controller {
+
+//===== SelectionFunction::EventDescriptor ====================================
+
+class SelectionFunction::EventDescriptor
+{
+public:
+    Point maMousePosition;
+    Point maMouseModelPosition;
+    model::SharedPageDescriptor mpHitDescriptor;
+    SdrPage* mpHitPage;
+    sal_uInt32 mnEventCode;
+    InsertionIndicatorHandler::Mode meDragMode;
+    bool mbIsLeaving;
+
+    EventDescriptor (
+        sal_uInt32 nEventType,
+        const MouseEvent& rEvent,
+        SlideSorter const & rSlideSorter);
+    EventDescriptor (
+        sal_uInt32 nEventType,
+        const AcceptDropEvent& rEvent,
+        const sal_Int8 nDragAction,
+        SlideSorter const & rSlideSorter);
+
+private:
+    /** Compute a numerical code that describes a mouse event and that can
+        be used for fast look up of the appropriate reaction.
+    */
+    sal_uInt32 EncodeMouseEvent (const MouseEvent& rEvent) const;
+
+    /** Compute a numerical code that describes the current state like
+        whether the selection rectangle is visible or whether the page under
+        the mouse or the one that has the focus is selected.
+    */
+    sal_uInt32 EncodeState() const;
+};
+
+//===== SelectionFunction::ModeHandler ========================================
+
+class SelectionFunction::ModeHandler
+{
+public:
+    ModeHandler (
+        SlideSorter& rSlideSorter,
+        SelectionFunction& rSelectionFunction,
+        const bool bIsMouseOverIndicatorAllowed);
+    virtual ~ModeHandler() COVERITY_NOEXCEPT_FALSE;
+
+    virtual Mode GetMode() const = 0;
+    virtual void Abort() = 0;
+    virtual void ProcessEvent (EventDescriptor& rDescriptor);
+
+    /** Set the selection to exactly the specified page and also set it as
+        the current page.
+    */
+    void SetCurrentPage (const model::SharedPageDescriptor& rpDescriptor);
+
+    /// Deselect all pages.
+    void DeselectAllPages();
+    void SelectOnePage (const model::SharedPageDescriptor& rpDescriptor);
+
+        /** When the view on which this selection function is working is the
+        main view then the view is switched to the regular editing view.
+    */
+    void SwitchView (const model::SharedPageDescriptor& rpDescriptor);
+
+    void StartDrag (
+        const Point& rMousePosition);
+
+    bool IsMouseOverIndicatorAllowed() const { return mbIsMouseOverIndicatorAllowed;}
+
+protected:
+    SlideSorter& mrSlideSorter;
+    SelectionFunction& mrSelectionFunction;
+
+    virtual bool ProcessButtonDownEvent (EventDescriptor& rDescriptor);
+    virtual bool ProcessButtonUpEvent (EventDescriptor& rDescriptor);
+    virtual bool ProcessMotionEvent (EventDescriptor& rDescriptor);
+    virtual bool ProcessDragEvent (EventDescriptor& rDescriptor);
+    virtual bool HandleUnprocessedEvent (EventDescriptor& rDescriptor);
+
+    void ReprocessEvent (EventDescriptor& rDescriptor);
+
+private:
+    const bool mbIsMouseOverIndicatorAllowed;
+};
+
+namespace {
+
+/** This is the default handler for processing events.  It activates the
+    multi selection or drag-and-drop when the right conditions are met.
+*/
+class NormalModeHandler : public SelectionFunction::ModeHandler
+{
+public:
+    NormalModeHandler (
+        SlideSorter& rSlideSorter,
+        SelectionFunction& rSelectionFunction);
+
+    virtual SelectionFunction::Mode GetMode() const override;
+    virtual void Abort() override;
+
+    void ResetButtonDownLocation();
+
+protected:
+    virtual bool ProcessButtonDownEvent (SelectionFunction::EventDescriptor& rDescriptor) override;
+    virtual bool ProcessButtonUpEvent (SelectionFunction::EventDescriptor& rDescriptor) override;
+    virtual bool ProcessMotionEvent (SelectionFunction::EventDescriptor& rDescriptor) override;
+    virtual bool ProcessDragEvent (SelectionFunction::EventDescriptor& rDescriptor) override;
+
+private:
+    ::std::optional<Point> maButtonDownLocation;
+
+    /** Select all pages between and including the selection anchor and the
+        specified page.
+    */
+    void RangeSelect (const model::SharedPageDescriptor& rpDescriptor);
+};
+
+/** Handle events during a multi selection, which typically is started by
+    pressing the left mouse button when not over a page.
+*/
+class MultiSelectionModeHandler : public SelectionFunction::ModeHandler
+{
+public:
+    /** Start a rectangle selection at the given position.
+    */
+    MultiSelectionModeHandler (
+        SlideSorter& rSlideSorter,
+        SelectionFunction& rSelectionFunction,
+        const Point& rMouseModelPosition,
+        const sal_uInt32 nEventCode);
+
+    virtual ~MultiSelectionModeHandler() override;
+
+    virtual SelectionFunction::Mode GetMode() const override;
+    virtual void Abort() override;
+    virtual void ProcessEvent (SelectionFunction::EventDescriptor& rDescriptor) override;
+
+    enum SelectionMode { SM_Normal, SM_Add, SM_Toggle };
+
+    void SetSelectionMode (const SelectionMode eSelectionMode);
+    void SetSelectionModeFromModifier (const sal_uInt32 nEventCode);
+
+protected:
+    virtual bool ProcessButtonUpEvent (SelectionFunction::EventDescriptor& rDescriptor) override;
+    virtual bool ProcessMotionEvent (SelectionFunction::EventDescriptor& rDescriptor) override;
+    virtual bool HandleUnprocessedEvent (SelectionFunction::EventDescriptor& rDescriptor) override;
+
+private:
+    SelectionMode meSelectionMode;
+    Point maSecondCorner;
+    PointerStyle maSavedPointer;
+    bool mbAutoScrollInstalled;
+    sal_Int32 mnAnchorIndex;
+    sal_Int32 mnSecondIndex;
+
+    void UpdateModelPosition (const Point& rMouseModelPosition);
+    void UpdateSelection();
+
+    /** Update the rectangle selection so that the given position becomes
+        the new second point of the selection rectangle.
+    */
+    void UpdatePosition (
+        const Point& rMousePosition,
+        const bool bAllowAutoScroll);
+
+    void UpdateSelectionState (
+        const model::SharedPageDescriptor& rpDescriptor,
+        const bool bIsInSelection) const;
+};
+
+/** Handle events during drag-and-drop.
+*/
+class DragAndDropModeHandler : public SelectionFunction::ModeHandler
+{
+public:
+    DragAndDropModeHandler (
+        SlideSorter& rSlideSorter,
+        SelectionFunction& rSelectionFunction,
+        const Point& rMousePosition,
+        vcl::Window* pWindow);
+    virtual ~DragAndDropModeHandler() override;
+
+    virtual SelectionFunction::Mode GetMode() const override;
+    virtual void Abort() override;
+
+protected:
+    virtual bool ProcessButtonUpEvent (SelectionFunction::EventDescriptor& rDescriptor) override;
+    virtual bool ProcessDragEvent (SelectionFunction::EventDescriptor& rDescriptor) override;
+
+private:
+    std::unique_ptr<DragAndDropContext, o3tl::default_delete<DragAndDropContext>> mpDragAndDropContext;
+};
+
+}
+
+//===== SelectionFunction =====================================================
+
+
+SelectionFunction::SelectionFunction (
+    SlideSorter& rSlideSorter,
+    SfxRequest& rRequest)
+    : FuPoor (
+        rSlideSorter.GetViewShell(),
+        rSlideSorter.GetContentWindow(),
+        &rSlideSorter.GetView(),
+        rSlideSorter.GetModel().GetDocument(),
+        rRequest),
+      mrSlideSorter(rSlideSorter),
+      mrController(mrSlideSorter.GetController()),
+      mnShiftKeySelectionAnchor(-1),
+      mpModeHandler(std::make_shared<NormalModeHandler>(rSlideSorter, *this))
+{
+}
+
+SelectionFunction::~SelectionFunction()
+{
+    mpModeHandler.reset();
+}
+
+rtl::Reference<FuPoor> SelectionFunction::Create(
+    SlideSorter& rSlideSorter,
+    SfxRequest& rRequest)
+{
+    rtl::Reference<FuPoor> xFunc( new SelectionFunction( rSlideSorter, rRequest ) );
+    return xFunc;
+}
+
+bool SelectionFunction::MouseButtonDown (const MouseEvent& rEvent)
+{
+    // remember button state for creation of own MouseEvents
+    SetMouseButtonCode (rEvent.GetButtons());
+    aMDPos = rEvent.GetPosPixel();
+
+    //  mpWindow->CaptureMouse();
+
+    ProcessMouseEvent(BUTTON_DOWN, rEvent);
+
+    return true;
+}
+
+bool SelectionFunction::MouseMove (const MouseEvent& rEvent)
+{
+    ProcessMouseEvent(MOUSE_MOTION, rEvent);
+    return true;
+}
+
+bool SelectionFunction::MouseButtonUp (const MouseEvent& rEvent)
+{
+    mrController.GetScrollBarManager().StopAutoScroll ();
+
+    ProcessMouseEvent(BUTTON_UP, rEvent);
+
+    return true;
+}
+
+void SelectionFunction::NotifyDragFinished()
+{
+    SwitchToNormalMode();
+}
+
+bool SelectionFunction::KeyInput (const KeyEvent& rEvent)
+{
+    view::SlideSorterView::DrawLock aDrawLock (mrSlideSorter);
+    PageSelector::BroadcastLock aBroadcastLock (mrSlideSorter);
+    PageSelector::UpdateLock aLock (mrSlideSorter);
+    FocusManager& rFocusManager (mrController.GetFocusManager());
+    bool bResult = false;
+
+    const vcl::KeyCode& rCode (rEvent.GetKeyCode());
+    switch (rCode.GetCode())
+    {
+        case KEY_RETURN:
+        {
+            model::SharedPageDescriptor pDescriptor (rFocusManager.GetFocusedPageDescriptor());
+            ViewShell* pViewShell = mrSlideSorter.GetViewShell();
+            if (rFocusManager.HasFocus() && pDescriptor && pViewShell!=nullptr)
+            {
+                // The Return key triggers different functions depending on
+                // whether the slide sorter is the main view or displayed in
+                // the right pane.
+                if (pViewShell->IsMainViewShell())
+                {
+                    mpModeHandler->SetCurrentPage(pDescriptor);
+                    mpModeHandler->SwitchView(pDescriptor);
+                }
+                else if (pViewShell->GetDispatcher() != nullptr)
+                {
+                    pViewShell->GetDispatcher()->Execute(
+                        SID_INSERTPAGE,
+                        SfxCallMode::ASYNCHRON | SfxCallMode::RECORD);
+                }
+                bResult = true;
+            }
+            break;
+        }
+
+        case KEY_TAB:
+            if ( ! rFocusManager.IsFocusShowing())
+            {
+                rFocusManager.ShowFocus();
+                bResult = true;
+            }
+            break;
+
+        case KEY_ESCAPE:
+            // When there is an active multiselection or drag-and-drop
+            // operation then stop that.
+            mpModeHandler->Abort();
+            SwitchToNormalMode();
+            bResult = true;
+            break;
+
+        case KEY_SPACE:
+        {
+            // Toggle the selection state.
+            model::SharedPageDescriptor pDescriptor (rFocusManager.GetFocusedPageDescriptor());
+            if (pDescriptor && rCode.IsMod1())
+            {
+                if (pDescriptor->HasState(model::PageDescriptor::ST_Selected))
+                    mrController.GetPageSelector().DeselectPage(pDescriptor, false);
+                else
+                    mrController.GetPageSelector().SelectPage(pDescriptor);
+            }
+            bResult = true;
+        }
+        break;
+
+        // Move the focus indicator left.
+        case KEY_LEFT:
+            MoveFocus(FocusManager::FocusMoveDirection::Left, rCode.IsShift(), rCode.IsMod1());
+            bResult = true;
+            break;
+
+        // Move the focus indicator right.
+        case KEY_RIGHT:
+            MoveFocus(FocusManager::FocusMoveDirection::Right, rCode.IsShift(), rCode.IsMod1());
+            bResult = true;
+            break;
+
+        // Move the focus indicator up.
+        case KEY_UP:
+            MoveFocus(FocusManager::FocusMoveDirection::Up, rCode.IsShift(), rCode.IsMod1());
+            bResult = true;
+            break;
+
+        // Move the focus indicator down.
+        case KEY_DOWN:
+            MoveFocus(FocusManager::FocusMoveDirection::Down, rCode.IsShift(), rCode.IsMod1());
+            bResult = true;
+            break;
+
+        // Go to previous page.  No wrap around.
+        case KEY_PAGEUP:
+            GotoNextPage(-1);
+            bResult = true;
+            break;
+
+        // Go to next page.  No wrap around...
+        case KEY_PAGEDOWN:
+            GotoNextPage(+1);
+            bResult = true;
+            break;
+
+        case KEY_HOME:
+            GotoPage(0);
+            bResult = true;
+            break;
+
+        case KEY_END:
+            GotoPage(mrSlideSorter.GetModel().GetPageCount()-1);
+            bResult = true;
+            break;
+
+        case KEY_DELETE:
+        case KEY_BACKSPACE:
+        {
+            if (mrSlideSorter.GetProperties()->IsUIReadOnly())
+                break;
+
+            mrController.GetSelectionManager()->DeleteSelectedPages(rCode.GetCode()==KEY_DELETE);
+
+            mnShiftKeySelectionAnchor = -1;
+            bResult = true;
+        }
+        break;
+
+        case KEY_F10:
+            if (rCode.IsShift())
+            {
+                mpModeHandler->SelectOnePage(
+                    mrSlideSorter.GetController().GetFocusManager().GetFocusedPageDescriptor());
+            }
+            break;
+
+        default:
+            break;
+    }
+
+    if ( ! bResult)
+        bResult = FuPoor::KeyInput(rEvent);
+
+    return bResult;
+}
+
+void SelectionFunction::MoveFocus (
+    const FocusManager::FocusMoveDirection eDirection,
+    const bool bIsShiftDown,
+    const bool bIsControlDown)
+{
+    // Remember the anchor of shift key multi selection.
+    if (bIsShiftDown)
+    {
+        if (mnShiftKeySelectionAnchor<0)
+        {
+            model::SharedPageDescriptor pFocusedDescriptor (
+                mrController.GetFocusManager().GetFocusedPageDescriptor());
+            mnShiftKeySelectionAnchor = pFocusedDescriptor->GetPageIndex();
+        }
+    }
+    else if ( ! bIsControlDown)
+        ResetShiftKeySelectionAnchor();
+
+    mrController.GetFocusManager().MoveFocus(eDirection);
+
+    PageSelector& rSelector (mrController.GetPageSelector());
+    model::SharedPageDescriptor pFocusedDescriptor (
+        mrController.GetFocusManager().GetFocusedPageDescriptor());
+    if (bIsShiftDown)
+    {
+        // When shift is pressed then select all pages in the range between
+        // the currently and the previously focused pages, including them.
+        if (pFocusedDescriptor)
+        {
+            sal_Int32 nPageRangeEnd (pFocusedDescriptor->GetPageIndex());
+            model::PageEnumeration aPages (
+                model::PageEnumerationProvider::CreateAllPagesEnumeration(
+                    mrSlideSorter.GetModel()));
+            while (aPages.HasMoreElements())
+            {
+                model::SharedPageDescriptor pDescriptor (aPages.GetNextElement());
+                if (pDescriptor)
+                {
+                    const sal_Int32 nPageIndex(pDescriptor->GetPageIndex());
+                    if ((nPageIndex>=mnShiftKeySelectionAnchor && nPageIndex<=nPageRangeEnd)
+                        || (nPageIndex<=mnShiftKeySelectionAnchor && nPageIndex>=nPageRangeEnd))
+                    {
+                        rSelector.SelectPage(pDescriptor);
+                    }
+                    else
+                    {
+                        rSelector.DeselectPage(pDescriptor);
+                    }
+                }
+            }
+        }
+    }
+    else if (bIsControlDown)
+    {
+        // When control is pressed then do not alter the selection or the
+        // current page, just move the focus.
+    }
+    else
+    {
+        // Without shift just select the focused page.
+        mpModeHandler->SelectOnePage(pFocusedDescriptor);
+    }
+}
+
+void SelectionFunction::DoCut()
+{
+    if ( ! mrSlideSorter.GetProperties()->IsUIReadOnly())
+    {
+        mrController.GetClipboard().DoCut();
+    }
+}
+
+void SelectionFunction::DoCopy()
+{
+    mrController.GetClipboard().DoCopy();
+}
+
+void SelectionFunction::DoPaste()
+{
+    if ( ! mrSlideSorter.GetProperties()->IsUIReadOnly())
+    {
+        mrController.GetClipboard().DoPaste();
+    }
+}
+
+bool SelectionFunction::cancel()
+{
+    mrController.GetFocusManager().ToggleFocus();
+    return true;
+}
+
+void SelectionFunction::GotoNextPage (int nOffset)
+{
+    model::SharedPageDescriptor pDescriptor
+        = mrController.GetCurrentSlideManager()->GetCurrentSlide();
+    if (pDescriptor)
+    {
+        SdPage* pPage = pDescriptor->GetPage();
+        OSL_ASSERT(pPage!=nullptr);
+        sal_Int32 nIndex = (pPage->GetPageNum()-1) / 2;
+        GotoPage(nIndex + nOffset);
+    }
+    ResetShiftKeySelectionAnchor();
+}
+
+void SelectionFunction::GotoPage (int nIndex)
+{
+    sal_uInt16 nPageCount = static_cast<sal_uInt16>(mrSlideSorter.GetModel().GetPageCount());
+
+    if (nIndex >= nPageCount)
+        nIndex = nPageCount - 1;
+    if (nIndex < 0)
+        nIndex = 0;
+
+    mrController.GetFocusManager().SetFocusedPage(nIndex);
+    model::SharedPageDescriptor pNextPageDescriptor (
+        mrSlideSorter.GetModel().GetPageDescriptor (nIndex));
+    if (pNextPageDescriptor)
+        mpModeHandler->SetCurrentPage(pNextPageDescriptor);
+    else
+    {
+        OSL_ASSERT(pNextPageDescriptor);
+    }
+    ResetShiftKeySelectionAnchor();
+}
+
+void SelectionFunction::ProcessMouseEvent (sal_uInt32 nEventType, const MouseEvent& rEvent)
+{
+    // #95491# remember button state for creation of own MouseEvents
+    SetMouseButtonCode (rEvent.GetButtons());
+
+    EventDescriptor aEventDescriptor (nEventType, rEvent, mrSlideSorter);
+    ProcessEvent(aEventDescriptor);
+}
+
+void SelectionFunction::MouseDragged (
+    const AcceptDropEvent& rEvent,
+    const sal_Int8 nDragAction)
+{
+    EventDescriptor aEventDescriptor (MOUSE_DRAG, rEvent, nDragAction, mrSlideSorter);
+    ProcessEvent(aEventDescriptor);
+}
+
+void SelectionFunction::ProcessEvent (EventDescriptor& rDescriptor)
+{
+    // The call to ProcessEvent may switch to another mode handler.
+    // Prevent the untimely destruction of the called handler  by acquiring a
+    // temporary reference here.
+    std::shared_ptr<ModeHandler> pModeHandler (mpModeHandler);
+    pModeHandler->ProcessEvent(rDescriptor);
+}
+
+static bool Match (
+    const sal_uInt32 nEventCode,
+    const sal_uInt32 nPositivePattern)
+{
+    return (nEventCode & nPositivePattern)==nPositivePattern;
+}
+
+void SelectionFunction::SwitchToNormalMode()
+{
+    if (mpModeHandler->GetMode() != NormalMode)
+        SwitchMode(std::make_shared<NormalModeHandler>(mrSlideSorter, *this));
+}
+
+void SelectionFunction::SwitchToDragAndDropMode (const Point& rMousePosition)
+{
+    if (mpModeHandler->GetMode() == DragAndDropMode)
+        return;
+
+    SwitchMode(std::make_shared<DragAndDropModeHandler>(mrSlideSorter, *this, rMousePosition, mpWindow));
+}
+
+void SelectionFunction::SwitchToMultiSelectionMode (
+    const Point& rMousePosition,
+    const sal_uInt32 nEventCode)
+{
+    if (mpModeHandler->GetMode() != MultiSelectionMode)
+        SwitchMode(std::make_shared<MultiSelectionModeHandler>(mrSlideSorter, *this, rMousePosition, nEventCode));
+}
+
+void SelectionFunction::SwitchMode (const std::shared_ptr<ModeHandler>& rpHandler)
+{
+    // Not all modes allow mouse over indicator.
+    if (mpModeHandler->IsMouseOverIndicatorAllowed() != rpHandler->IsMouseOverIndicatorAllowed())
+    {
+        if ( ! rpHandler->IsMouseOverIndicatorAllowed())
+        {
+            mrSlideSorter.GetView().SetPageUnderMouse(model::SharedPageDescriptor());
+        }
+        else
+            mrSlideSorter.GetView().UpdatePageUnderMouse();
+    }
+
+    mpModeHandler = rpHandler;
+}
+
+void SelectionFunction::ResetShiftKeySelectionAnchor()
+{
+    mnShiftKeySelectionAnchor = -1;
+}
+
+void SelectionFunction::ResetMouseAnchor()
+{
+    if (mpModeHandler && mpModeHandler->GetMode() == NormalMode)
+    {
+        std::shared_ptr<NormalModeHandler> pHandler (
+            std::dynamic_pointer_cast<NormalModeHandler>(mpModeHandler));
+        if (pHandler)
+            pHandler->ResetButtonDownLocation();
+    }
+}
+
+//===== EventDescriptor =======================================================
+
+SelectionFunction::EventDescriptor::EventDescriptor (
+    const sal_uInt32 nEventType,
+    const MouseEvent& rEvent,
+    SlideSorter const & rSlideSorter)
+    : maMousePosition(rEvent.GetPosPixel()),
+      mpHitPage(),
+      mnEventCode(nEventType),
+      meDragMode(InsertionIndicatorHandler::MoveMode),
+      mbIsLeaving(false)
+{
+    maMouseModelPosition = rSlideSorter.GetContentWindow()->PixelToLogic(maMousePosition);
+    mpHitDescriptor = rSlideSorter.GetController().GetPageAt(maMousePosition);
+    if (mpHitDescriptor)
+    {
+        mpHitPage = mpHitDescriptor->GetPage();
+    }
+
+    mnEventCode |= EncodeMouseEvent(rEvent);
+    mnEventCode |= EncodeState();
+
+    // Detect the mouse leaving the window.  When not button is pressed then
+    // we can call IsLeaveWindow at the event.  Otherwise we have to make an
+    // explicit test.
+    mbIsLeaving = rEvent.IsLeaveWindow()
+        || ! ::tools::Rectangle(Point(0,0),
+             rSlideSorter.GetContentWindow()->GetOutputSizePixel()).Contains(maMousePosition);
+}
+
+SelectionFunction::EventDescriptor::EventDescriptor (
+    const sal_uInt32 nEventType,
+    const AcceptDropEvent& rEvent,
+    const sal_Int8 nDragAction,
+    SlideSorter const & rSlideSorter)
+    : maMousePosition(rEvent.maPosPixel),
+      mpHitPage(),
+      mnEventCode(nEventType),
+      meDragMode(InsertionIndicatorHandler::GetModeFromDndAction(nDragAction)),
+      mbIsLeaving(false)
+{
+    maMouseModelPosition = rSlideSorter.GetContentWindow()->PixelToLogic(maMousePosition);
+    mpHitDescriptor = rSlideSorter.GetController().GetPageAt(maMousePosition);
+    if (mpHitDescriptor)
+    {
+        mpHitPage = mpHitDescriptor->GetPage();
+    }
+
+    mnEventCode |= EncodeState();
+
+    // Detect the mouse leaving the window.  When not button is pressed then
+    // we can call IsLeaveWindow at the event.  Otherwise we have to make an
+    // explicit test.
+    mbIsLeaving = rEvent.mbLeaving
+        || ! ::tools::Rectangle(Point(0,0),
+             rSlideSorter.GetContentWindow()->GetOutputSizePixel()).Contains(maMousePosition);
+}
+
+sal_uInt32 SelectionFunction::EventDescriptor::EncodeMouseEvent (
+    const MouseEvent& rEvent) const
+{
+    // Initialize with the type of mouse event.
+    sal_uInt32 nEventCode (mnEventCode & (BUTTON_DOWN | BUTTON_UP | MOUSE_MOTION));
+
+    // Detect the affected button.
+    switch (rEvent.GetButtons())
+    {
+        case MOUSE_LEFT:   nEventCode |= LEFT_BUTTON; break;
+        case MOUSE_RIGHT:  nEventCode |= RIGHT_BUTTON; break;
+        case MOUSE_MIDDLE: nEventCode |= MIDDLE_BUTTON; break;
+    }
+
+    // Detect the number of clicks.
+    switch (rEvent.GetClicks())
+    {
+        case 1: nEventCode |= SINGLE_CLICK; break;
+        case 2: nEventCode |= DOUBLE_CLICK; break;
+    }
+
+    // Detect pressed modifier keys.
+    if (rEvent.IsShift())
+        nEventCode |= SHIFT_MODIFIER;
+    if (rEvent.IsMod1())
+        nEventCode |= CONTROL_MODIFIER;
+
+    return nEventCode;
+}
+
+sal_uInt32 SelectionFunction::EventDescriptor::EncodeState() const
+{
+    sal_uInt32 nEventCode (0);
+
+    // Detect whether the event has happened over a page object.
+    if (mpHitPage!=nullptr && mpHitDescriptor)
+    {
+        if (mpHitDescriptor->HasState(model::PageDescriptor::ST_Selected))
+            nEventCode |= OVER_SELECTED_PAGE;
+        else
+            nEventCode |= OVER_UNSELECTED_PAGE;
+    }
+
+    return nEventCode;
+}
+
+//===== SelectionFunction::ModeHandler ========================================
+
+SelectionFunction::ModeHandler::ModeHandler (
+    SlideSorter& rSlideSorter,
+    SelectionFunction& rSelectionFunction,
+    const bool bIsMouseOverIndicatorAllowed)
+    : mrSlideSorter(rSlideSorter),
+      mrSelectionFunction(rSelectionFunction),
+      mbIsMouseOverIndicatorAllowed(bIsMouseOverIndicatorAllowed)
+{
+}
+
+SelectionFunction::ModeHandler::~ModeHandler() COVERITY_NOEXCEPT_FALSE
+{
+}
+
+void SelectionFunction::ModeHandler::ReprocessEvent (EventDescriptor& rDescriptor)
+{
+    mrSelectionFunction.ProcessEvent(rDescriptor);
+}
+
+void SelectionFunction::ModeHandler::ProcessEvent (
+    SelectionFunction::EventDescriptor& rDescriptor)
+{
+    PageSelector::BroadcastLock aBroadcastLock (mrSlideSorter);
+    PageSelector::UpdateLock aUpdateLock (mrSlideSorter);
+
+    bool bIsProcessed (false);
+    switch (rDescriptor.mnEventCode & (BUTTON_DOWN | BUTTON_UP | MOUSE_MOTION | MOUSE_DRAG))
+    {
+        case BUTTON_DOWN:
+            bIsProcessed = ProcessButtonDownEvent(rDescriptor);
+            break;
+
+        case BUTTON_UP:
+            bIsProcessed = ProcessButtonUpEvent(rDescriptor);
+            break;
+
+        case MOUSE_MOTION:
+            bIsProcessed = ProcessMotionEvent(rDescriptor);
+            break;
+
+        case MOUSE_DRAG:
+            bIsProcessed = ProcessDragEvent(rDescriptor);
+            break;
+    }
+
+    if ( ! bIsProcessed)
+        HandleUnprocessedEvent(rDescriptor);
+}
+
+bool SelectionFunction::ModeHandler::ProcessButtonDownEvent (EventDescriptor&)
+{
+    return false;
+}
+
+bool SelectionFunction::ModeHandler::ProcessButtonUpEvent (EventDescriptor&)
+{
+    mrSelectionFunction.SwitchToNormalMode();
+    return false;
+}
+
+bool SelectionFunction::ModeHandler::ProcessMotionEvent (EventDescriptor& rDescriptor)
+{
+    if (mbIsMouseOverIndicatorAllowed)
+        mrSlideSorter.GetView().UpdatePageUnderMouse(rDescriptor.maMousePosition);
+
+    if (rDescriptor.mbIsLeaving)
+    {
+        mrSelectionFunction.SwitchToNormalMode();
+        mrSlideSorter.GetView().SetPageUnderMouse(model::SharedPageDescriptor());
+
+        return true;
+    }
+    else
+        return false;
+}
+
+bool SelectionFunction::ModeHandler::ProcessDragEvent (EventDescriptor&)
+{
+    return false;
+}
+
+bool SelectionFunction::ModeHandler::HandleUnprocessedEvent (EventDescriptor&)
+{
+    return false;
+}
+
+void SelectionFunction::ModeHandler::SetCurrentPage (
+    const model::SharedPageDescriptor& rpDescriptor)
+{
+    SelectOnePage(rpDescriptor);
+    mrSlideSorter.GetController().GetCurrentSlideManager()->SwitchCurrentSlide(rpDescriptor);
+}
+
+void SelectionFunction::ModeHandler::DeselectAllPages()
+{
+    mrSlideSorter.GetController().GetPageSelector().DeselectAllPages();
+    mrSelectionFunction.ResetShiftKeySelectionAnchor();
+}
+
+void SelectionFunction::ModeHandler::SelectOnePage (
+    const model::SharedPageDescriptor& rpDescriptor)
+{
+    DeselectAllPages();
+    mrSlideSorter.GetController().GetPageSelector().SelectPage(rpDescriptor);
+}
+
+void SelectionFunction::ModeHandler::SwitchView (const model::SharedPageDescriptor& rpDescriptor)
+{
+    // Switch to the draw view.  This is done only when the current
+    // view is the main view.
+    ViewShell* pViewShell = mrSlideSorter.GetViewShell();
+    if (pViewShell==nullptr || !pViewShell->IsMainViewShell())
+        return;
+
+    if (rpDescriptor && rpDescriptor->GetPage()!=nullptr)
+    {
+        mrSlideSorter.GetModel().GetDocument()->SetSelected(rpDescriptor->GetPage(), true);
+        pViewShell->GetFrameView()->SetSelectedPage(
+            (rpDescriptor->GetPage()->GetPageNum()-1)/2);
+    }
+    if (mrSlideSorter.GetViewShellBase() != nullptr)
+        framework::FrameworkHelper::Instance(*mrSlideSorter.GetViewShellBase())->RequestView(
+            framework::FrameworkHelper::msImpressViewURL,
+            framework::FrameworkHelper::msCenterPaneURL);
+}
+
+void SelectionFunction::ModeHandler::StartDrag (
+    const Point& rMousePosition)
+{
+    // Do not start a drag-and-drop operation when one is already active.
+    // (when dragging pages from one document into another, pressing a
+    // modifier key can trigger a MouseMotion event in the originating
+    // window (focus still in there).  Together with the mouse button pressed
+    // (drag-and-drop is active) this triggers the start of drag-and-drop.)
+    if (SD_MOD()->pTransferDrag != nullptr)
+        return;
+
+    if ( ! mrSlideSorter.GetProperties()->IsUIReadOnly())
+    {
+        mrSelectionFunction.SwitchToDragAndDropMode(rMousePosition);
+    }
+}
+
+//===== NormalModeHandler =====================================================
+
+NormalModeHandler::NormalModeHandler (
+    SlideSorter& rSlideSorter,
+    SelectionFunction& rSelectionFunction)
+    : ModeHandler(rSlideSorter, rSelectionFunction, true)
+{
+}
+
+SelectionFunction::Mode NormalModeHandler::GetMode() const
+{
+    return SelectionFunction::NormalMode;
+}
+
+void NormalModeHandler::Abort()
+{
+}
+
+bool NormalModeHandler::ProcessButtonDownEvent (
+    SelectionFunction::EventDescriptor& rDescriptor)
+{
+    // Remember the location where the left button is pressed.  With
+    // that we can filter away motion events that are caused by key
+    // presses.  We also can tune the minimal motion distance that
+    // triggers a drag-and-drop operation.
+    if ((rDescriptor.mnEventCode & BUTTON_DOWN) != 0)
+        maButtonDownLocation = rDescriptor.maMousePosition;
+
+    switch (rDescriptor.mnEventCode)
+    {
+        case BUTTON_DOWN | LEFT_BUTTON | SINGLE_CLICK | OVER_UNSELECTED_PAGE:
+            SetCurrentPage(rDescriptor.mpHitDescriptor);
+            break;
+
+        case BUTTON_DOWN | LEFT_BUTTON | SINGLE_CLICK | OVER_SELECTED_PAGE:
+            break;
+
+        case BUTTON_DOWN | LEFT_BUTTON | DOUBLE_CLICK | OVER_SELECTED_PAGE:
+        case BUTTON_DOWN | LEFT_BUTTON | DOUBLE_CLICK | OVER_UNSELECTED_PAGE:
+            // A double click always shows the selected slide in the center
+            // pane in an edit view.
+            SetCurrentPage(rDescriptor.mpHitDescriptor);
+            SwitchView(rDescriptor.mpHitDescriptor);
+            break;
+
+        case BUTTON_DOWN | LEFT_BUTTON | SINGLE_CLICK | OVER_SELECTED_PAGE | SHIFT_MODIFIER:
+        case BUTTON_DOWN | LEFT_BUTTON | SINGLE_CLICK | OVER_UNSELECTED_PAGE | SHIFT_MODIFIER:
+            // Range selection with the shift modifier.
+            RangeSelect(rDescriptor.mpHitDescriptor);
+            break;
+
+            // Right button for context menu.
+        case BUTTON_DOWN | RIGHT_BUTTON | SINGLE_CLICK | OVER_UNSELECTED_PAGE:
+            // Single right click and shift+F10 select as preparation to
+            // show the context menu.  Change the selection only when the
+            // page under the mouse is not selected.  In this case the
+            // selection is set to this single page.  Otherwise the
+            // selection is not modified.
+            SetCurrentPage(rDescriptor.mpHitDescriptor);
+            break;
+
+        case BUTTON_DOWN | RIGHT_BUTTON | SINGLE_CLICK | OVER_SELECTED_PAGE:
+            // Do not change the selection.  Just adjust the insertion indicator.
+            break;
+
+        case BUTTON_DOWN | RIGHT_BUTTON | SINGLE_CLICK | NOT_OVER_PAGE:
+            // Remember the current selection so that when a multi selection
+            // is started, we can restore the previous selection.
+            mrSlideSorter.GetModel().SaveCurrentSelection();
+            DeselectAllPages();
+            break;
+
+        case ANY_MODIFIER(BUTTON_DOWN | LEFT_BUTTON | SINGLE_CLICK | NOT_OVER_PAGE):
+            // Remember the current selection so that when a multi selection
+            // is started, we can restore the previous selection.
+            mrSlideSorter.GetModel().SaveCurrentSelection();
+            DeselectAllPages();
+            break;
+
+        case BUTTON_DOWN | LEFT_BUTTON | DOUBLE_CLICK | NOT_OVER_PAGE:
+        {
+            // Insert a new slide:
+            // First of all we need to set the insertion indicator which sets the
+            // position where the new slide will be inserted.
+            std::shared_ptr<InsertionIndicatorHandler> pInsertionIndicatorHandler
+                = mrSlideSorter.GetController().GetInsertionIndicatorHandler();
+
+            pInsertionIndicatorHandler->Start(false);
+            pInsertionIndicatorHandler->UpdatePosition(
+                    rDescriptor.maMousePosition,
+                    InsertionIndicatorHandler::MoveMode);
+
+            mrSlideSorter.GetController().GetSelectionManager()->SetInsertionPosition(
+                pInsertionIndicatorHandler->GetInsertionPageIndex());
+
+            mrSlideSorter.GetViewShell()->GetDispatcher()->Execute(
+                SID_INSERTPAGE,
+                SfxCallMode::ASYNCHRON | SfxCallMode::RECORD);
+
+            pInsertionIndicatorHandler->End(Animator::AM_Immediate);
+
+            break;
+        }
+
+        default:
+            return false;
+    }
+    return true;
+}
+
+bool NormalModeHandler::ProcessButtonUpEvent (
+    SelectionFunction::EventDescriptor& rDescriptor)
+{
+    bool bIsProcessed (true);
+    switch (rDescriptor.mnEventCode)
+    {
+        case BUTTON_UP | LEFT_BUTTON | SINGLE_CLICK | OVER_SELECTED_PAGE:
+            SetCurrentPage(rDescriptor.mpHitDescriptor);
+            break;
+
+            // Multi selection with the control modifier.
+        case BUTTON_UP | LEFT_BUTTON | SINGLE_CLICK | OVER_SELECTED_PAGE | CONTROL_MODIFIER:
+            mrSlideSorter.GetController().GetPageSelector().DeselectPage(
+                rDescriptor.mpHitDescriptor);
+            break;
+
+        case BUTTON_UP | LEFT_BUTTON | SINGLE_CLICK | OVER_UNSELECTED_PAGE | CONTROL_MODIFIER:
+            mrSlideSorter.GetController().GetPageSelector().SelectPage(
+                rDescriptor.mpHitDescriptor);
+            mrSlideSorter.GetView().SetPageUnderMouse(rDescriptor.mpHitDescriptor);
+            break;
+        case BUTTON_UP | LEFT_BUTTON | SINGLE_CLICK | NOT_OVER_PAGE:
+            break;
+
+        default:
+            bIsProcessed = false;
+            break;
+    }
+    mrSelectionFunction.SwitchToNormalMode();
+    return bIsProcessed;
+}
+
+bool NormalModeHandler::ProcessMotionEvent (
+    SelectionFunction::EventDescriptor& rDescriptor)
+{
+    if (ModeHandler::ProcessMotionEvent(rDescriptor))
+        return true;
+
+    bool bIsProcessed (true);
+    switch (rDescriptor.mnEventCode)
+    {
+        // A mouse motion without visible substitution starts that.
+        case ANY_MODIFIER(MOUSE_MOTION | LEFT_BUTTON | SINGLE_CLICK | OVER_UNSELECTED_PAGE):
+        case ANY_MODIFIER(MOUSE_MOTION | LEFT_BUTTON | SINGLE_CLICK | OVER_SELECTED_PAGE):
+        {
+            if (maButtonDownLocation)
+            {
+                const sal_Int32 nDistance(std::max(
+                    std::abs(maButtonDownLocation->X() - rDescriptor.maMousePosition.X()),
+                    std::abs(maButtonDownLocation->Y() - rDescriptor.maMousePosition.Y())));
+                if (nDistance > 3)
+                    StartDrag(rDescriptor.maMousePosition);
+            }
+            break;
+        }
+
+        // A mouse motion not over a page starts a rectangle selection.
+        case ANY_MODIFIER(MOUSE_MOTION | LEFT_BUTTON | SINGLE_CLICK | NOT_OVER_PAGE):
+            mrSelectionFunction.SwitchToMultiSelectionMode(
+                rDescriptor.maMouseModelPosition,
+                rDescriptor.mnEventCode);
+            break;
+
+        default:
+            bIsProcessed = false;
+            break;
+    }
+    return bIsProcessed;
+}
+
+bool NormalModeHandler::ProcessDragEvent (SelectionFunction::EventDescriptor& rDescriptor)
+{
+    mrSelectionFunction.SwitchToDragAndDropMode(rDescriptor.maMousePosition);
+    ReprocessEvent(rDescriptor);
+    return true;
+}
+
+void NormalModeHandler::RangeSelect (const model::SharedPageDescriptor& rpDescriptor)
+{
+    PageSelector::UpdateLock aLock (mrSlideSorter);
+    PageSelector& rSelector (mrSlideSorter.GetController().GetPageSelector());
+
+    model::SharedPageDescriptor pAnchor (rSelector.GetSelectionAnchor());
+    DeselectAllPages();
+
+    if (!pAnchor)
+        return;
+
+    // Select all pages between the anchor and the given one, including
+    // the two.
+    const sal_uInt16 nAnchorIndex ((pAnchor->GetPage()->GetPageNum()-1) / 2);
+    const sal_uInt16 nOtherIndex ((rpDescriptor->GetPage()->GetPageNum()-1) / 2);
+
+    // Iterate over all pages in the range.  Start with the anchor
+    // page.  This way the PageSelector will recognize it again as
+    // anchor (the first selected page after a DeselectAllPages()
+    // becomes the anchor.)
+    const sal_uInt16 nStep ((nAnchorIndex < nOtherIndex) ? +1 : -1);
+    sal_uInt16 nIndex (nAnchorIndex);
+    while (true)
+    {
+        rSelector.SelectPage(nIndex);
+        if (nIndex == nOtherIndex)
+            break;
+        nIndex = nIndex + nStep;
+    }
+}
+
+void NormalModeHandler::ResetButtonDownLocation()
+{
+    maButtonDownLocation = ::std::optional<Point>();
+}
+
+//===== MultiSelectionModeHandler =============================================
+
+MultiSelectionModeHandler::MultiSelectionModeHandler (
+    SlideSorter& rSlideSorter,
+    SelectionFunction& rSelectionFunction,
+    const Point& rMouseModelPosition,
+    const sal_uInt32 nEventCode)
+    : ModeHandler(rSlideSorter, rSelectionFunction, false),
+      meSelectionMode(SM_Normal),
+      maSecondCorner(rMouseModelPosition),
+      maSavedPointer(mrSlideSorter.GetContentWindow()->GetPointer()),
+      mbAutoScrollInstalled(false),
+      mnAnchorIndex(-1),
+      mnSecondIndex(-1)
+{
+
+    mrSlideSorter.GetContentWindow()->SetPointer(PointerStyle::Text);
+    SetSelectionModeFromModifier(nEventCode);
+}
+
+MultiSelectionModeHandler::~MultiSelectionModeHandler()
+{
+    if (mbAutoScrollInstalled)
+    {
+        //a call to this handler's MultiSelectionModeHandler::UpdatePosition
+        //may be still waiting to be called back
+        mrSlideSorter.GetController().GetScrollBarManager().clearAutoScrollFunctor();
+    }
+    mrSlideSorter.GetContentWindow()->SetPointer(maSavedPointer);
+}
+
+SelectionFunction::Mode MultiSelectionModeHandler::GetMode() const
+{
+    return SelectionFunction::MultiSelectionMode;
+}
+
+void MultiSelectionModeHandler::Abort()
+{
+    mrSlideSorter.GetView().RequestRepaint(mrSlideSorter.GetModel().RestoreSelection());
+}
+
+void MultiSelectionModeHandler::ProcessEvent (
+    SelectionFunction::EventDescriptor& rDescriptor)
+{
+    // During a multi selection we do not want sudden jumps of the
+    // visible area caused by moving newly selected pages into view.
+    // Therefore disable that temporarily.  The disabled object is
+    // released at the end of the event processing, after the focus and
+    // current slide have been updated.
+    VisibleAreaManager::TemporaryDisabler aDisabler (mrSlideSorter);
+
+    ModeHandler::ProcessEvent(rDescriptor);
+}
+
+bool MultiSelectionModeHandler::ProcessButtonUpEvent (
+    SelectionFunction::EventDescriptor& rDescriptor)
+{
+    if (mbAutoScrollInstalled)
+    {
+        //a call to this handler's MultiSelectionModeHandler::UpdatePosition
+        //may be still waiting to be called back
+        mrSlideSorter.GetController().GetScrollBarManager().clearAutoScrollFunctor();
+        mbAutoScrollInstalled = false;
+    }
+
+    if (Match(rDescriptor.mnEventCode, BUTTON_UP | LEFT_BUTTON | SINGLE_CLICK))
+    {
+        mrSelectionFunction.SwitchToNormalMode();
+        return true;
+    }
+    else
+        return false;
+}
+
+bool MultiSelectionModeHandler::ProcessMotionEvent (
+    SelectionFunction::EventDescriptor& rDescriptor)
+{
+    // The selection rectangle is visible.  Handle events accordingly.
+    if (Match(rDescriptor.mnEventCode, MOUSE_MOTION | LEFT_BUTTON | SINGLE_CLICK))
+    {
+        SetSelectionModeFromModifier(rDescriptor.mnEventCode);
+        UpdatePosition(rDescriptor.maMousePosition, true);
+        return true;
+    }
+    else
+        return false;
+}
+
+bool MultiSelectionModeHandler::HandleUnprocessedEvent (
+    SelectionFunction::EventDescriptor& rDescriptor)
+{
+    if ( ! ModeHandler::HandleUnprocessedEvent(rDescriptor))
+    {
+        // If the event has not been processed then stop multi selection.
+        mrSelectionFunction.SwitchToNormalMode();
+        ReprocessEvent(rDescriptor);
+    }
+    return true;
+}
+
+void MultiSelectionModeHandler::UpdatePosition (
+    const Point& rMousePosition,
+    const bool bAllowAutoScroll)
+{
+    VisibleAreaManager::TemporaryDisabler aDisabler (mrSlideSorter);
+
+    // Convert window coordinates into model coordinates (we need the
+    // window coordinates for auto-scrolling because that remains
+    // constant while scrolling.)
+    sd::Window *pWindow (mrSlideSorter.GetContentWindow().get());
+    const Point aMouseModelPosition (pWindow->PixelToLogic(rMousePosition));
+
+    bool bDoAutoScroll = bAllowAutoScroll && mrSlideSorter.GetController().GetScrollBarManager().AutoScroll(
+        rMousePosition,
+        [this, &rMousePosition] () { return this->UpdatePosition(rMousePosition, false); });
+
+    if (!bDoAutoScroll)
+        UpdateModelPosition(aMouseModelPosition);
+
+    mbAutoScrollInstalled |= bDoAutoScroll;
+}
+
+void MultiSelectionModeHandler::SetSelectionModeFromModifier (
+    const sal_uInt32 nEventCode)
+{
+    switch (nEventCode & MODIFIER_MASK)
+    {
+        case NO_MODIFIER:
+            SetSelectionMode(SM_Normal);
+            break;
+
+        case SHIFT_MODIFIER:
+            SetSelectionMode(SM_Add);
+            break;
+
+        case CONTROL_MODIFIER:
+            SetSelectionMode(SM_Toggle);
+            break;
+    }
+}
+
+void MultiSelectionModeHandler::SetSelectionMode (const SelectionMode eSelectionMode)
+{
+    if (meSelectionMode != eSelectionMode)
+    {
+        meSelectionMode = eSelectionMode;
+        UpdateSelection();
+    }
+}
+
+void MultiSelectionModeHandler::UpdateSelectionState (
+    const model::SharedPageDescriptor& rpDescriptor,
+    const bool bIsInSelection) const
+{
+    // Determine whether the page was selected before the rectangle
+    // selection was started.
+    const bool bWasSelected (rpDescriptor->HasState(model::PageDescriptor::ST_WasSelected));
+
+    // Combine the two selection states depending on the selection mode.
+    bool bSelect (false);
+    switch(meSelectionMode)
+    {
+        case SM_Normal:
+            bSelect = bIsInSelection;
+            break;
+
+        case SM_Add:
+            bSelect = bIsInSelection || bWasSelected;
+            break;
+
+        case SM_Toggle:
+            if (bIsInSelection)
+                bSelect = !bWasSelected;
+            else
+                bSelect = bWasSelected;
+            break;
+    }
+
+    // Set the new selection state.
+    if (bSelect)
+        mrSlideSorter.GetController().GetPageSelector().SelectPage(rpDescriptor);
+    else
+        mrSlideSorter.GetController().GetPageSelector().DeselectPage(rpDescriptor);
+}
+
+void MultiSelectionModeHandler::UpdateModelPosition (const Point& rMouseModelPosition)
+{
+    maSecondCorner = rMouseModelPosition;
+    UpdateSelection();
+}
+
+void MultiSelectionModeHandler::UpdateSelection()
+{
+    view::SlideSorterView::DrawLock aLock (mrSlideSorter);
+
+    model::SlideSorterModel& rModel (mrSlideSorter.GetModel());
+    const sal_Int32 nPageCount (rModel.GetPageCount());
+
+    const sal_Int32 nIndexUnderMouse (
+        mrSlideSorter.GetView().GetLayouter().GetIndexAtPoint (
+            maSecondCorner,
+            false,
+            false));
+    if (nIndexUnderMouse < 0 || nIndexUnderMouse >= nPageCount)
+        return;
+
+    if (mnAnchorIndex < 0)
+        mnAnchorIndex = nIndexUnderMouse;
+    mnSecondIndex = nIndexUnderMouse;
+
+    Range aRange (mnAnchorIndex, mnSecondIndex);
+    aRange.Justify();
+
+    for (sal_Int32 nIndex=0; nIndex<nPageCount; ++nIndex)
+    {
+        UpdateSelectionState(rModel.GetPageDescriptor(nIndex), aRange.Contains(nIndex));
+    }
+}
+
+//===== DragAndDropModeHandler ================================================
+
+DragAndDropModeHandler::DragAndDropModeHandler (
+    SlideSorter& rSlideSorter,
+    SelectionFunction& rSelectionFunction,
+    const Point& rMousePosition,
+    vcl::Window* pWindow)
+    : ModeHandler(rSlideSorter, rSelectionFunction, false)
+{
+    SdTransferable* pDragTransferable = SD_MOD()->pTransferDrag;
+    if (pDragTransferable==nullptr && mrSlideSorter.GetViewShell() != nullptr)
+    {
+        SlideSorterViewShell* pSlideSorterViewShell
+            = dynamic_cast<SlideSorterViewShell*>(mrSlideSorter.GetViewShell());
+        if (pSlideSorterViewShell != nullptr)
+            pSlideSorterViewShell->StartDrag(rMousePosition, pWindow);
+        pDragTransferable = SD_MOD()->pTransferDrag;
+    }
+
+    mpDragAndDropContext.reset(new DragAndDropContext(mrSlideSorter));
+    mrSlideSorter.GetController().GetInsertionIndicatorHandler()->Start(
+        pDragTransferable != nullptr
+            && pDragTransferable->GetView()==&mrSlideSorter.GetView());
+}
+
+DragAndDropModeHandler::~DragAndDropModeHandler()
+{
+    if (mpDragAndDropContext)
+    {
+        // Disconnect the substitution handler from this selection function.
+        mpDragAndDropContext->SetTargetSlideSorter();
+        mpDragAndDropContext.reset();
+    }
+    mrSlideSorter.GetController().GetInsertionIndicatorHandler()->End(Animator::AM_Animated);
+}
+
+SelectionFunction::Mode DragAndDropModeHandler::GetMode() const
+{
+    return SelectionFunction::DragAndDropMode;
+}
+
+void DragAndDropModeHandler::Abort()
+{
+    mrSlideSorter.GetController().GetClipboard().Abort();
+    if (mpDragAndDropContext)
+        mpDragAndDropContext->Dispose();
+    //    mrSlideSorter.GetView().RequestRepaint(mrSlideSorter.GetModel().RestoreSelection());
+}
+
+bool DragAndDropModeHandler::ProcessButtonUpEvent (
+    SelectionFunction::EventDescriptor& rDescriptor)
+{
+    if (Match(rDescriptor.mnEventCode, BUTTON_UP | LEFT_BUTTON))
+    {
+        // The following Process() call may lead to the destruction
+        // of rDescriptor.mpHitDescriptor so release our reference to it.
+        rDescriptor.mpHitDescriptor.reset();
+        mrSelectionFunction.SwitchToNormalMode();
+        return true;
+    }
+    else
+        return false;
+}
+
+bool DragAndDropModeHandler::ProcessDragEvent (SelectionFunction::EventDescriptor& rDescriptor)
+{
+    OSL_ASSERT(mpDragAndDropContext);
+
+    if (rDescriptor.mbIsLeaving)
+    {
+        mrSelectionFunction.SwitchToNormalMode();
+    }
+    else if (mpDragAndDropContext)
+    {
+        mpDragAndDropContext->UpdatePosition(
+            rDescriptor.maMousePosition,
+            rDescriptor.meDragMode, true);
+    }
+
+    return true;
+}
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/controller/SlsSelectionManager.cxx b/sd/source/ui/slidesorter/controller/SlsSelectionManager.cxx
new file mode 100644
index 000000000..e1f75b21c
--- /dev/null
+++ b/sd/source/ui/slidesorter/controller/SlsSelectionManager.cxx
@@ -0,0 +1,309 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <controller/SlsSelectionManager.hxx>
+
+#include <SlideSorter.hxx>
+#include <controller/SlideSorterController.hxx>
+#include <controller/SlsCurrentSlideManager.hxx>
+#include <controller/SlsFocusManager.hxx>
+#include <controller/SlsPageSelector.hxx>
+#include <controller/SlsSelectionObserver.hxx>
+#include <model/SlideSorterModel.hxx>
+#include <model/SlsPageEnumerationProvider.hxx>
+#include <model/SlsPageDescriptor.hxx>
+#include <view/SlideSorterView.hxx>
+#include <tools/diagnose_ex.h>
+#include <drawdoc.hxx>
+#include <sdpage.hxx>
+#include <drawview.hxx>
+#include <DrawViewShell.hxx>
+#include <ViewShellBase.hxx>
+#include <svx/svxids.hrc>
+#include <com/sun/star/drawing/XMasterPagesSupplier.hpp>
+#include <com/sun/star/drawing/XDrawPagesSupplier.hpp>
+
+
+#include <sdresid.hxx>
+#include <strings.hrc>
+#include <app.hrc>
+
+using namespace ::com::sun::star;
+using namespace ::com::sun::star::drawing;
+using namespace ::com::sun::star::uno;
+using namespace ::sd::slidesorter::model;
+using namespace ::sd::slidesorter::view;
+using namespace ::sd::slidesorter::controller;
+
+namespace sd::slidesorter::controller {
+
+SelectionManager::SelectionManager (SlideSorter& rSlideSorter)
+    : mrSlideSorter(rSlideSorter),
+      mrController(rSlideSorter.GetController()),
+      mnInsertionPosition(-1),
+      mpSelectionObserver(std::make_shared<SelectionObserver>(rSlideSorter))
+{
+}
+
+SelectionManager::~SelectionManager()
+{
+}
+
+void SelectionManager::DeleteSelectedPages (const bool bSelectFollowingPage)
+{
+    // Create some locks to prevent updates of the model, view, selection
+    // state while modifying any of them.
+    SlideSorterController::ModelChangeLock aLock (mrController);
+    SlideSorterView::DrawLock aDrawLock (mrSlideSorter);
+    PageSelector::UpdateLock aSelectionLock (mrSlideSorter);
+
+    // Hide focus.
+    bool bIsFocusShowing = mrController.GetFocusManager().IsFocusShowing();
+    if (bIsFocusShowing)
+        mrController.GetFocusManager().ToggleFocus();
+
+    // Store pointers to all selected page descriptors.  This is necessary
+    // because the pages get deselected when the first one is deleted.
+    model::PageEnumeration aPageEnumeration (
+        PageEnumerationProvider::CreateSelectedPagesEnumeration(mrSlideSorter.GetModel()));
+    ::std::vector<SdPage*> aSelectedPages;
+    sal_Int32 nNewCurrentSlide (-1);
+    while (aPageEnumeration.HasMoreElements())
+    {
+        SharedPageDescriptor pDescriptor (aPageEnumeration.GetNextElement());
+        aSelectedPages.push_back(pDescriptor->GetPage());
+        if (bSelectFollowingPage || nNewCurrentSlide<0)
+            nNewCurrentSlide = pDescriptor->GetPageIndex();
+    }
+    if (aSelectedPages.empty())
+        return;
+
+    // Determine the slide to select (and thereby make the current slide)
+    // after the deletion.
+    if (bSelectFollowingPage)
+        nNewCurrentSlide -= aSelectedPages.size() - 1;
+    else
+        --nNewCurrentSlide;
+
+    const auto pViewShell = mrSlideSorter.GetViewShell();
+    const auto pDrawViewShell = pViewShell ? std::dynamic_pointer_cast<sd::DrawViewShell>(pViewShell->GetViewShellBase().GetMainViewShell()) : nullptr;
+    const auto pDrawView = pDrawViewShell ? pDrawViewShell->GetDrawView() : nullptr;
+
+    if (pDrawView)
+        pDrawView->BlockPageOrderChangedHint(true);
+
+    // Proper naming for the undo action
+    OUString sUndoComment(SdResId(STR_UNDO_DELETEPAGES));
+    if (mrSlideSorter.GetView().GetDoc().GetDocumentType() == DocumentType::Draw)
+        sUndoComment = SdResId(STR_UNDO_DELETEPAGES_DRAW);
+
+    // The actual deletion of the selected pages is done in one of two
+    // helper functions.  They are specialized for normal respectively for
+    // master pages.
+    mrSlideSorter.GetView().BegUndo (sUndoComment);
+    if (mrSlideSorter.GetModel().GetEditMode() == EditMode::Page)
+        DeleteSelectedNormalPages(aSelectedPages);
+    else
+        DeleteSelectedMasterPages(aSelectedPages);
+    mrSlideSorter.GetView().EndUndo ();
+
+    mrController.HandleModelChange();
+    aLock.Release();
+    if (pDrawView)
+    {
+        assert(pDrawViewShell);
+        pDrawView->BlockPageOrderChangedHint(false);
+        pDrawViewShell->ResetActualPage();
+    }
+
+    // Show focus and move it to next valid location.
+    if (bIsFocusShowing)
+        mrController.GetFocusManager().ToggleFocus();
+
+    // Set the new current slide.
+    if (nNewCurrentSlide < 0)
+        nNewCurrentSlide = 0;
+    else if (nNewCurrentSlide >= mrSlideSorter.GetModel().GetPageCount())
+        nNewCurrentSlide = mrSlideSorter.GetModel().GetPageCount()-1;
+    mrController.GetPageSelector().CountSelectedPages();
+    mrController.GetPageSelector().SelectPage(nNewCurrentSlide);
+    mrController.GetFocusManager().SetFocusedPage(nNewCurrentSlide);
+}
+
+void SelectionManager::DeleteSelectedNormalPages (const ::std::vector<SdPage*>& rSelectedPages)
+{
+    // Prepare the deletion via the UNO API.
+    OSL_ASSERT(mrSlideSorter.GetModel().GetEditMode() == EditMode::Page);
+
+    try
+    {
+        Reference<drawing::XDrawPagesSupplier> xDrawPagesSupplier( mrSlideSorter.GetModel().GetDocument()->getUnoModel(), UNO_QUERY_THROW );
+        Reference<drawing::XDrawPages> xPages( xDrawPagesSupplier->getDrawPages(), UNO_SET_THROW );
+
+        // Iterate over all pages that were selected when this method was called
+        // and delete the draw page the notes page. The iteration is done in
+        // reverse order so that when one slide is not deleted (to avoid an
+        // empty document) the remaining slide is the first one.
+        ::std::vector<SdPage*>::const_reverse_iterator aI;
+        for (aI=rSelectedPages.rbegin(); aI!=rSelectedPages.rend(); ++aI)
+        {
+            // Do not delete the last slide in the document.
+            if (xPages->getCount() <= 1)
+                break;
+
+            const sal_uInt16 nPage (model::FromCoreIndex((*aI)->GetPageNum()));
+
+            Reference< XDrawPage > xPage( xPages->getByIndex( nPage ), UNO_QUERY_THROW );
+            xPages->remove(xPage);
+        }
+    }
+    catch( Exception& )
+    {
+        TOOLS_WARN_EXCEPTION( "sd", "SelectionManager::DeleteSelectedNormalPages()");
+    }
+}
+
+void SelectionManager::DeleteSelectedMasterPages (const ::std::vector<SdPage*>& rSelectedPages)
+{
+    // Prepare the deletion via the UNO API.
+    OSL_ASSERT(mrSlideSorter.GetModel().GetEditMode() == EditMode::MasterPage);
+
+    try
+    {
+        Reference<drawing::XMasterPagesSupplier> xDrawPagesSupplier( mrSlideSorter.GetModel().GetDocument()->getUnoModel(), UNO_QUERY_THROW );
+        Reference<drawing::XDrawPages> xPages( xDrawPagesSupplier->getMasterPages(), UNO_SET_THROW );
+
+        // Iterate over all pages that were selected when this method was called
+        // and delete the draw page the notes page. The iteration is done in
+        // reverse order so that when one slide is not deleted (to avoid an
+        // empty document) the remaining slide is the first one.
+        ::std::vector<SdPage*>::const_reverse_iterator aI;
+        for (aI=rSelectedPages.rbegin(); aI!=rSelectedPages.rend(); ++aI)
+        {
+            // Do not delete the last slide in the document.
+            if (xPages->getCount() <= 1)
+                break;
+
+            const sal_uInt16 nPage (model::FromCoreIndex((*aI)->GetPageNum()));
+
+            Reference< XDrawPage > xPage( xPages->getByIndex( nPage ), UNO_QUERY_THROW );
+            xPages->remove(xPage);
+        }
+    }
+    catch( Exception& )
+    {
+        TOOLS_WARN_EXCEPTION( "sd", "SelectionManager::DeleteSelectedMasterPages()");
+    }
+}
+
+void SelectionManager::SelectionHasChanged ()
+{
+    ViewShell* pViewShell = mrSlideSorter.GetViewShell();
+    if (pViewShell == nullptr)
+        return;
+
+    pViewShell->Invalidate (SID_EXPAND_PAGE);
+    pViewShell->Invalidate (SID_SUMMARY_PAGE);
+    pViewShell->Invalidate(SID_SHOW_SLIDE);
+    pViewShell->Invalidate(SID_HIDE_SLIDE);
+    pViewShell->Invalidate(SID_DELETE_PAGE);
+    pViewShell->Invalidate(SID_DELETE_MASTER_PAGE);
+    pViewShell->Invalidate(SID_ASSIGN_LAYOUT);
+
+    // StatusBar
+    pViewShell->Invalidate (SID_STATUS_PAGE);
+    pViewShell->Invalidate (SID_STATUS_LAYOUT);
+    pViewShell->Invalidate (SID_SCALE);
+
+    OSL_ASSERT(mrController.GetCurrentSlideManager());
+    SharedPageDescriptor pDescriptor(mrController.GetCurrentSlideManager()->GetCurrentSlide());
+    if (pDescriptor)
+        pViewShell->UpdatePreview(pDescriptor->GetPage());
+
+    // Tell the selection change listeners that the selection has changed.
+    for (const auto& rLink : maSelectionChangeListeners)
+    {
+        rLink.Call(nullptr);
+    }
+
+    // Reset the insertion position: until set again it is calculated from
+    // the current selection.
+    mnInsertionPosition = -1;
+}
+
+void SelectionManager::AddSelectionChangeListener (const Link<LinkParamNone*,void>& rListener)
+{
+    if (::std::find (
+        maSelectionChangeListeners.begin(),
+        maSelectionChangeListeners.end(),
+        rListener) == maSelectionChangeListeners.end())
+    {
+        maSelectionChangeListeners.push_back (rListener);
+    }
+}
+
+void SelectionManager::RemoveSelectionChangeListener(const Link<LinkParamNone*,void>& rListener)
+{
+    maSelectionChangeListeners.erase (
+        ::std::find (
+            maSelectionChangeListeners.begin(),
+            maSelectionChangeListeners.end(),
+            rListener));
+}
+
+sal_Int32 SelectionManager::GetInsertionPosition() const
+{
+    sal_Int32 nInsertionPosition (mnInsertionPosition);
+    if (nInsertionPosition < 0)
+    {
+        model::PageEnumeration aSelectedPages
+            (model::PageEnumerationProvider::CreateSelectedPagesEnumeration(
+                mrSlideSorter.GetModel()));
+        // Initialize (for the case of an empty selection) with the position
+        // at the end of the document.
+        nInsertionPosition = mrSlideSorter.GetModel().GetPageCount();
+        while (aSelectedPages.HasMoreElements())
+        {
+            const sal_Int32 nPosition (aSelectedPages.GetNextElement()->GetPage()->GetPageNum());
+            // Convert *2+1 index to straight index (n-1)/2 after the page
+            // (+1).
+            nInsertionPosition = model::FromCoreIndex(nPosition) + 1;
+        }
+
+    }
+    return nInsertionPosition;
+}
+
+void SelectionManager::SetInsertionPosition (const sal_Int32 nInsertionPosition)
+{
+    if (nInsertionPosition < 0)
+        mnInsertionPosition = -1;
+    else if (nInsertionPosition > mrSlideSorter.GetModel().GetPageCount())
+    {
+        // Assert but then ignore invalid values.
+        OSL_ASSERT(nInsertionPosition<=mrSlideSorter.GetModel().GetPageCount());
+        return;
+    }
+    else
+        mnInsertionPosition = nInsertionPosition;
+}
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/controller/SlsSelectionObserver.cxx b/sd/source/ui/slidesorter/controller/SlsSelectionObserver.cxx
new file mode 100644
index 000000000..8fb0493a0
--- /dev/null
+++ b/sd/source/ui/slidesorter/controller/SlsSelectionObserver.cxx
@@ -0,0 +1,139 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <SlideSorter.hxx>
+#include <controller/SlideSorterController.hxx>
+#include <controller/SlsSelectionManager.hxx>
+#include <controller/SlsSelectionObserver.hxx>
+#include <controller/SlsPageSelector.hxx>
+#include <controller/SlsFocusManager.hxx>
+#include <sdpage.hxx>
+#include <osl/diagnose.h>
+
+namespace sd::slidesorter::controller
+{
+SelectionObserver::Context::Context(SlideSorter const& rSlideSorter)
+    : mpSelectionObserver(
+          rSlideSorter.GetController().GetSelectionManager()->GetSelectionObserver())
+{
+    if (mpSelectionObserver)
+        mpSelectionObserver->StartObservation();
+}
+
+SelectionObserver::Context::~Context() COVERITY_NOEXCEPT_FALSE
+{
+    if (mpSelectionObserver)
+        mpSelectionObserver->EndObservation();
+}
+
+void SelectionObserver::Context::Abort()
+{
+    if (mpSelectionObserver)
+    {
+        mpSelectionObserver->AbortObservation();
+        mpSelectionObserver.reset();
+    }
+}
+
+//===== SelectionObserver =====================================================
+
+SelectionObserver::SelectionObserver(SlideSorter& rSlideSorter)
+    : mrSlideSorter(rSlideSorter)
+    , mbIsObservationActive(false)
+    , mbPageEventOccurred(false)
+{
+}
+
+SelectionObserver::~SelectionObserver() {}
+
+void SelectionObserver::NotifyPageEvent(const SdrPage* pSdrPage)
+{
+    if (!mbIsObservationActive)
+        return;
+
+    mbPageEventOccurred = true;
+
+    const SdPage* pPage = dynamic_cast<const SdPage*>(pSdrPage);
+    if (pPage == nullptr)
+        return;
+
+    //NotifyPageEvent is called for add, remove, *and* change position so for
+    //the change position case we must ensure we don't end up with the slide
+    //duplicated in our list
+    std::vector<const SdPage*>::iterator iPage(
+        std::find(maInsertedPages.begin(), maInsertedPages.end(), pPage));
+    if (iPage != maInsertedPages.end())
+        maInsertedPages.erase(iPage);
+
+    if (pPage->IsInserted())
+        maInsertedPages.push_back(pPage);
+}
+
+void SelectionObserver::StartObservation()
+{
+    OSL_ASSERT(!mbIsObservationActive);
+    maInsertedPages.clear();
+    mbIsObservationActive = true;
+}
+
+void SelectionObserver::AbortObservation()
+{
+    OSL_ASSERT(mbIsObservationActive);
+    mbIsObservationActive = false;
+    maInsertedPages.clear();
+}
+
+void SelectionObserver::EndObservation()
+{
+    OSL_ASSERT(mbIsObservationActive);
+    mbIsObservationActive = false;
+
+    if (!mbPageEventOccurred)
+        return;
+
+    PageSelector& rSelector(mrSlideSorter.GetController().GetPageSelector());
+    PageSelector::UpdateLock aUpdateLock(mrSlideSorter);
+    rSelector.DeselectAllPages();
+    if (!maInsertedPages.empty())
+    {
+        // Select the inserted pages.
+        for (const auto& rpPage : maInsertedPages)
+        {
+            rSelector.SelectPage(rpPage);
+        }
+        maInsertedPages.clear();
+    }
+
+    aUpdateLock.Release();
+    FocusManager& rFocusManager = mrSlideSorter.GetController().GetFocusManager();
+    bool bSuccess = rFocusManager.SetFocusedPageToCurrentPage();
+    // tdf#129346 nothing currently selected, select something, if possible
+    // but (tdf#129346) only if setting focus to current page failed
+    if (rSelector.GetPageCount() && rSelector.GetSelectedPageCount() == 0)
+    {
+        if (bSuccess)
+            rSelector.SelectPage(rFocusManager.GetFocusedPageDescriptor());
+        else
+            rSelector.SelectPage(0);
+    }
+}
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/controller/SlsSlotManager.cxx b/sd/source/ui/slidesorter/controller/SlsSlotManager.cxx
new file mode 100644
index 000000000..52e05557e
--- /dev/null
+++ b/sd/source/ui/slidesorter/controller/SlsSlotManager.cxx
@@ -0,0 +1,1284 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <controller/SlsSlotManager.hxx>
+#include <SlideSorter.hxx>
+#include <SlideSorterViewShell.hxx>
+#include <controller/SlideSorterController.hxx>
+#include <controller/SlsClipboard.hxx>
+#include <controller/SlsCurrentSlideManager.hxx>
+#include <controller/SlsInsertionIndicatorHandler.hxx>
+#include <controller/SlsPageSelector.hxx>
+#include <controller/SlsSelectionFunction.hxx>
+#include <controller/SlsSelectionManager.hxx>
+#include <model/SlideSorterModel.hxx>
+#include <model/SlsPageEnumerationProvider.hxx>
+#include <model/SlsPageDescriptor.hxx>
+#include <view/SlideSorterView.hxx>
+#include <view/SlsLayouter.hxx>
+#include <framework/FrameworkHelper.hxx>
+#include <Window.hxx>
+#include <fupoor.hxx>
+#include <fucushow.hxx>
+#include <fusldlg.hxx>
+#include <fuexpand.hxx>
+#include <fusumry.hxx>
+#include <slideshow.hxx>
+#include <app.hrc>
+#include <strings.hrc>
+#include <sdresid.hxx>
+#include <unokywds.hxx>
+#include <drawdoc.hxx>
+#include <DrawDocShell.hxx>
+#include <ViewShellBase.hxx>
+#include <ViewShellImplementation.hxx>
+#include <sdpage.hxx>
+#include <sdxfer.hxx>
+#include <helpids.h>
+#include <unmodpg.hxx>
+#include <DrawViewShell.hxx>
+#include <sdabstdlg.hxx>
+#include <sdmod.hxx>
+
+#include <vcl/uitest/logger.hxx>
+#include <vcl/uitest/eventdescription.hxx>
+
+#include <sfx2/request.hxx>
+#include <sfx2/viewfrm.hxx>
+#include <sfx2/bindings.hxx>
+#include <sfx2/sidebar/Sidebar.hxx>
+#include <svx/svxids.hrc>
+#include <svx/svxdlg.hxx>
+#include <svl/intitem.hxx>
+#include <svl/stritem.hxx>
+#include <svl/whiter.hxx>
+#include <svl/itempool.hxx>
+#include <com/sun/star/drawing/XMasterPagesSupplier.hpp>
+#include <com/sun/star/drawing/XDrawPages.hpp>
+#include <osl/diagnose.h>
+
+#include <memory>
+
+using namespace ::com::sun::star;
+using namespace ::com::sun::star::uno;
+using namespace ::com::sun::star::beans;
+
+namespace sd::slidesorter::controller {
+
+namespace {
+
+/** The state of a set of slides with respect to being excluded from the
+    slide show.
+*/
+enum SlideExclusionState {UNDEFINED, EXCLUDED, INCLUDED, MIXED};
+
+/** Return for the given set of slides whether they included are
+    excluded from the slide show.
+*/
+SlideExclusionState GetSlideExclusionState (model::PageEnumeration& rPageSet);
+
+} // end of anonymous namespace
+
+
+namespace {
+
+void collectUIInformation(std::map<OUString, OUString>&& aParameters, const OUString& rAction)
+{
+    EventDescription aDescription;
+    aDescription.aID = "impress_win_or_draw_win";
+    aDescription.aParameters = std::move(aParameters);
+    aDescription.aAction = rAction;
+    aDescription.aKeyWord = "ImpressWindowUIObject";
+    aDescription.aParent = "MainWindow";
+
+    UITestLogger::getInstance().logEvent(aDescription);
+}
+
+}
+
+SlotManager::SlotManager (SlideSorter& rSlideSorter)
+    : mrSlideSorter(rSlideSorter)
+{
+}
+
+void SlotManager::FuTemporary (SfxRequest& rRequest)
+{
+    SdDrawDocument* pDocument = mrSlideSorter.GetModel().GetDocument();
+
+    SlideSorterViewShell* pShell
+        = dynamic_cast<SlideSorterViewShell*>(mrSlideSorter.GetViewShell());
+    if (pShell == nullptr)
+        return;
+
+    switch (rRequest.GetSlot())
+    {
+        case SID_PRESENTATION:
+        case SID_PRESENTATION_CURRENT_SLIDE:
+        case SID_REHEARSE_TIMINGS:
+            slideshowhelp::ShowSlideShow(rRequest, *mrSlideSorter.GetModel().GetDocument());
+            pShell->Cancel();
+            rRequest.Done();
+            break;
+
+        case SID_HIDE_SLIDE:
+            ChangeSlideExclusionState(model::SharedPageDescriptor(), true);
+            break;
+
+        case SID_SHOW_SLIDE:
+            ChangeSlideExclusionState(model::SharedPageDescriptor(), false);
+            break;
+
+        case SID_PAGES_PER_ROW:
+            if (rRequest.GetArgs() != nullptr)
+            {
+                const SfxUInt16Item* pPagesPerRow = rRequest.GetArg<SfxUInt16Item>(SID_PAGES_PER_ROW);
+                if (pPagesPerRow != nullptr)
+                {
+                    sal_Int32 nColumnCount = pPagesPerRow->GetValue();
+                    // Force the given number of columns by setting
+                    // the minimal and maximal number of columns to
+                    // the same value.
+                    mrSlideSorter.GetView().GetLayouter().SetColumnCount (
+                        nColumnCount, nColumnCount);
+                    // Force a repaint and re-layout.
+                    pShell->ArrangeGUIElements ();
+                    // Rearrange the UI-elements controlled by the
+                    // controller and force a rearrangement of the
+                    // view.
+                    mrSlideSorter.GetController().Rearrange(true);
+                }
+            }
+            rRequest.Done();
+            break;
+
+        case SID_SELECTALL:
+            mrSlideSorter.GetController().GetPageSelector().SelectAllPages();
+            rRequest.Done();
+            break;
+
+        case SID_SLIDE_TRANSITIONS_PANEL:
+        {
+            // First make sure that the sidebar is visible
+            pShell->GetViewFrame()->ShowChildWindow(SID_SIDEBAR);
+            ::sfx2::sidebar::Sidebar::ShowPanel(
+                u"SdSlideTransitionPanel",
+                pShell->GetViewFrame()->GetFrame().GetFrameInterface());
+            rRequest.Ignore ();
+            break;
+        }
+
+        case SID_MASTER_SLIDES_PANEL:
+        {
+            // First make sure that the sidebar is visible
+            pShell->GetViewFrame()->ShowChildWindow(SID_SIDEBAR);
+            ::sfx2::sidebar::Sidebar::ShowPanel(
+                u"SdAllMasterPagesPanel",
+                pShell->GetViewFrame()->GetFrame().GetFrameInterface());
+            rRequest.Ignore ();
+            break;
+        }
+
+        case SID_PRESENTATION_DLG:
+            FuSlideShowDlg::Create (
+                pShell,
+                mrSlideSorter.GetContentWindow(),
+                &mrSlideSorter.GetView(),
+                pDocument,
+                rRequest);
+            break;
+
+        case SID_CUSTOMSHOW_DLG:
+            FuCustomShowDlg::Create (
+                pShell,
+                mrSlideSorter.GetContentWindow(),
+                &mrSlideSorter.GetView(),
+                pDocument,
+                rRequest);
+                break;
+
+        case SID_EXPAND_PAGE:
+            FuExpandPage::Create (
+                pShell,
+                mrSlideSorter.GetContentWindow(),
+                &mrSlideSorter.GetView(),
+                pDocument,
+                rRequest);
+            break;
+
+        case SID_SUMMARY_PAGE:
+            FuSummaryPage::Create (
+                pShell,
+                mrSlideSorter.GetContentWindow(),
+                &mrSlideSorter.GetView(),
+                pDocument,
+                rRequest);
+            break;
+
+        case SID_INSERTPAGE:
+        case SID_INSERT_MASTER_PAGE:
+            InsertSlide(rRequest);
+            rRequest.Done();
+            break;
+
+        case SID_DUPLICATE_PAGE:
+            DuplicateSelectedSlides(rRequest);
+            rRequest.Done();
+            break;
+
+        case SID_DELETE_PAGE:
+        case SID_DELETE_MASTER_PAGE:
+        case SID_DELETE: // we need SID_CUT to handle the delete key
+            // (DEL -> accelerator -> SID_CUT).
+            if (mrSlideSorter.GetModel().GetPageCount() > 1)
+            {
+                mrSlideSorter.GetView().EndTextEditAllViews();
+                mrSlideSorter.GetController().GetSelectionManager()->DeleteSelectedPages();
+            }
+
+            rRequest.Done();
+            break;
+
+        case SID_RENAMEPAGE:
+        case SID_RENAME_MASTER_PAGE:
+            RenameSlide (rRequest);
+            rRequest.Done ();
+            break;
+
+        case SID_ASSIGN_LAYOUT:
+        {
+            pShell->mpImpl->AssignLayout( rRequest, PageKind::Standard );
+            rRequest.Done ();
+        }
+        break;
+
+        case SID_PHOTOALBUM:
+        {
+            SdAbstractDialogFactory* pFact = SdAbstractDialogFactory::Create();
+            vcl::Window* pWin = mrSlideSorter.GetContentWindow();
+            ScopedVclPtr<VclAbstractDialog> pDlg(pFact->CreateSdPhotoAlbumDialog(
+                pWin ? pWin->GetFrameWeld() : nullptr,
+                pDocument));
+            pDlg->Execute();
+            rRequest.Done ();
+        }
+        break;
+
+        case SID_REMOTE_DLG:
+        {
+#ifdef ENABLE_SDREMOTE
+            SdAbstractDialogFactory* pFact = SdAbstractDialogFactory::Create();
+            vcl::Window* pWin = mrSlideSorter.GetContentWindow();
+            ScopedVclPtr<VclAbstractDialog> pDlg(pFact->CreateRemoteDialog(pWin ? pWin->GetFrameWeld() : nullptr));
+            pDlg->Execute();
+#endif
+        }
+        break;
+
+        default:
+            break;
+    }
+}
+
+void SlotManager::FuPermanent (SfxRequest& rRequest)
+{
+    ViewShell* pShell = mrSlideSorter.GetViewShell();
+    if (pShell == nullptr)
+        return;
+
+    if(pShell->GetCurrentFunction().is())
+    {
+        rtl::Reference<FuPoor> xEmpty;
+        if (pShell->GetOldFunction() == pShell->GetCurrentFunction())
+            pShell->SetOldFunction(xEmpty);
+
+        pShell->GetCurrentFunction()->Deactivate();
+        pShell->SetCurrentFunction(xEmpty);
+    }
+
+    switch(rRequest.GetSlot())
+    {
+        case SID_OBJECT_SELECT:
+            pShell->SetCurrentFunction( SelectionFunction::Create(mrSlideSorter, rRequest) );
+            rRequest.Done();
+            break;
+
+        default:
+                break;
+    }
+
+    if(pShell->GetOldFunction().is())
+    {
+        pShell->GetOldFunction()->Deactivate();
+        rtl::Reference<FuPoor> xEmpty;
+        pShell->SetOldFunction(xEmpty);
+    }
+
+    if(pShell->GetCurrentFunction().is())
+    {
+        pShell->GetCurrentFunction()->Activate();
+        pShell->SetOldFunction(pShell->GetCurrentFunction());
+    }
+
+    //! that's only until ENUM-Slots ?are
+    //  Invalidate( SID_OBJECT_SELECT );
+}
+
+void SlotManager::FuSupport (SfxRequest& rRequest)
+{
+    switch (rRequest.GetSlot())
+    {
+        case SID_STYLE_FAMILY:
+            if (rRequest.GetArgs() != nullptr)
+            {
+                SdDrawDocument* pDocument
+                    = mrSlideSorter.GetModel().GetDocument();
+                if (pDocument != nullptr)
+                {
+                    const SfxPoolItem& rItem (
+                        rRequest.GetArgs()->Get(SID_STYLE_FAMILY));
+                    pDocument->GetDocSh()->SetStyleFamily(
+                        static_cast<SfxStyleFamily>(static_cast<const SfxUInt16Item&>(rItem).GetValue()));
+                }
+            }
+            break;
+
+        case SID_PASTE:
+        {
+            SdTransferable* pTransferClip = SD_MOD()->pTransferClip;
+            if( pTransferClip )
+            {
+                SfxObjectShell* pTransferDocShell = pTransferClip->GetDocShell().get();
+
+                DrawDocShell* pDocShell = dynamic_cast<DrawDocShell*>(pTransferDocShell);
+                if (pDocShell && pDocShell->GetDoc()->GetPageCount() > 1)
+                {
+                    mrSlideSorter.GetController().GetClipboard().HandleSlotCall(rRequest);
+                    break;
+                }
+            }
+            ViewShellBase* pBase = mrSlideSorter.GetViewShellBase();
+            if (pBase != nullptr)
+            {
+                std::shared_ptr<DrawViewShell> pDrawViewShell (
+                    std::dynamic_pointer_cast<DrawViewShell>(pBase->GetMainViewShell()));
+                if (pDrawViewShell != nullptr)
+                    pDrawViewShell->FuSupport(rRequest);
+            }
+        }
+        break;
+
+        case SID_CUT:
+        case SID_COPY:
+        case SID_DELETE:
+            mrSlideSorter.GetView().EndTextEditAllViews();
+            mrSlideSorter.GetController().GetClipboard().HandleSlotCall(rRequest);
+            break;
+
+        case SID_DRAWINGMODE:
+        case SID_NOTES_MODE:
+        case SID_HANDOUT_MASTER_MODE:
+        case SID_SLIDE_SORTER_MODE:
+        case SID_OUTLINE_MODE:
+        {
+            ViewShellBase* pBase = mrSlideSorter.GetViewShellBase();
+            if (pBase != nullptr)
+            {
+                framework::FrameworkHelper::Instance(*pBase)->HandleModeChangeSlot(
+                    rRequest.GetSlot(), rRequest);
+                rRequest.Done();
+            }
+            break;
+        }
+
+        case SID_UNDO:
+        {
+            SlideSorterViewShell* pViewShell
+                = dynamic_cast<SlideSorterViewShell*>(mrSlideSorter.GetViewShell());
+            if (pViewShell != nullptr)
+            {
+                pViewShell->ImpSidUndo (rRequest);
+            }
+            break;
+        }
+
+        case SID_REDO:
+        {
+            SlideSorterViewShell* pViewShell
+                = dynamic_cast<SlideSorterViewShell*>(mrSlideSorter.GetViewShell());
+            if (pViewShell != nullptr)
+            {
+                pViewShell->ImpSidRedo (rRequest);
+            }
+            break;
+        }
+
+        default:
+            break;
+    }
+}
+
+void SlotManager::ExecCtrl (SfxRequest& rRequest)
+{
+    ViewShell* pViewShell = mrSlideSorter.GetViewShell();
+    sal_uInt16 nSlot = rRequest.GetSlot();
+    switch (nSlot)
+    {
+        case SID_RELOAD:
+        {
+            // empty Undo-Manager
+            mrSlideSorter.GetModel().GetDocument()->GetDocSh()->ClearUndoBuffer();
+
+            // normal forwarding to ViewFrame for execution
+            if (pViewShell != nullptr)
+                pViewShell->GetViewFrame()->ExecuteSlot(rRequest);
+
+            // has to be finished right away
+            return;
+        }
+
+        case SID_OUTPUT_QUALITY_COLOR:
+        case SID_OUTPUT_QUALITY_GRAYSCALE:
+        case SID_OUTPUT_QUALITY_BLACKWHITE:
+        case SID_OUTPUT_QUALITY_CONTRAST:
+        {
+            // flush page cache
+            if (pViewShell != nullptr)
+                pViewShell->ExecReq (rRequest);
+            break;
+        }
+
+        case SID_MAIL_SCROLLBODY_PAGEDOWN:
+        {
+            if (pViewShell != nullptr)
+                pViewShell->ExecReq (rRequest);
+            break;
+        }
+
+        case SID_OPT_LOCALE_CHANGED:
+        {
+            mrSlideSorter.GetController().UpdateAllPages();
+            if (pViewShell != nullptr)
+                pViewShell->UpdatePreview (pViewShell->GetActualPage());
+            rRequest.Done();
+            break;
+        }
+
+        case SID_SEARCH_DLG:
+            // We have to handle the SID_SEARCH_DLG slot explicitly because
+            // in some cases (when the slide sorter is displayed in the
+            // center pane) we want to disable the search dialog.  Therefore
+            // we have to handle the execution of that slot as well.
+            // We try to do that by forwarding the request to the view frame
+            // of the view shell.
+            if (pViewShell != nullptr)
+                pViewShell->GetViewFrame()->ExecuteSlot(rRequest);
+            break;
+
+        default:
+            break;
+    }
+}
+
+void SlotManager::GetAttrState (SfxItemSet& rSet)
+{
+    // Iterate over all items.
+    SfxWhichIter aIter (rSet);
+    sal_uInt16 nWhich = aIter.FirstWhich();
+    while (nWhich)
+    {
+        sal_uInt16 nSlotId (nWhich);
+        if (SfxItemPool::IsWhich(nWhich) && mrSlideSorter.GetViewShell()!=nullptr)
+            nSlotId = mrSlideSorter.GetViewShell()->GetPool().GetSlotId(nWhich);
+        switch (nSlotId)
+        {
+            case SID_PAGES_PER_ROW:
+                rSet.Put (
+                    SfxUInt16Item (
+                        nSlotId,
+                        static_cast<sal_uInt16>(mrSlideSorter.GetView().GetLayouter().GetColumnCount())
+                        )
+                    );
+            break;
+        }
+        nWhich = aIter.NextWhich();
+    }
+}
+
+void SlotManager::GetMenuState (SfxItemSet& rSet)
+{
+    EditMode eEditMode = mrSlideSorter.GetModel().GetEditMode();
+    ViewShell* pShell = mrSlideSorter.GetViewShell();
+    DrawDocShell* pDocShell = mrSlideSorter.GetModel().GetDocument()->GetDocSh();
+
+    if (pShell!=nullptr && pShell->GetCurrentFunction().is())
+    {
+        sal_uInt16 nSId = pShell->GetCurrentFunction()->GetSlotID();
+
+        rSet.Put( SfxBoolItem( nSId, true ) );
+    }
+    rSet.Put( SfxBoolItem( SID_DRAWINGMODE, false ) );
+    rSet.Put( SfxBoolItem( SID_SLIDE_SORTER_MODE, true ) );
+    rSet.Put( SfxBoolItem( SID_OUTLINE_MODE, false ) );
+    rSet.Put( SfxBoolItem( SID_NOTES_MODE, false ) );
+    rSet.Put( SfxBoolItem( SID_HANDOUT_MASTER_MODE, false ) );
+
+    if (pShell!=nullptr && pShell->IsMainViewShell())
+    {
+        rSet.DisableItem(SID_SPELL_DIALOG);
+        rSet.DisableItem(SID_SEARCH_DLG);
+    }
+
+    if (SfxItemState::DEFAULT == rSet.GetItemState(SID_EXPAND_PAGE))
+    {
+        bool bDisable = true;
+        if (eEditMode == EditMode::Page)
+        {
+            // At least one of the selected pages has to contain an outline
+            // presentation objects in order to enable the expand page menu
+            // entry.
+            model::PageEnumeration aSelectedPages (
+                model::PageEnumerationProvider::CreateSelectedPagesEnumeration(
+                    mrSlideSorter.GetModel()));
+            while (aSelectedPages.HasMoreElements())
+            {
+                SdPage* pPage = aSelectedPages.GetNextElement()->GetPage();
+                SdrObject* pObj = pPage->GetPresObj(PresObjKind::Outline);
+                if (pObj!=nullptr )
+                {
+                    if( !pObj->IsEmptyPresObj() )
+                    {
+                        bDisable = false;
+                    }
+                    else
+                    {
+                        // check if the object is in edit, then if it's temporarily not empty
+                        SdrTextObj* pTextObj = dynamic_cast< SdrTextObj* >( pObj );
+                        if( pTextObj )
+                        {
+                            if( pTextObj->CanCreateEditOutlinerParaObject() )
+                            {
+                                bDisable = false;
+                            }
+                        }
+                    }
+                }
+            }
+        }
+
+        if (bDisable)
+            rSet.DisableItem (SID_EXPAND_PAGE);
+    }
+
+    if (SfxItemState::DEFAULT == rSet.GetItemState(SID_SUMMARY_PAGE))
+    {
+        bool bDisable = true;
+        if (eEditMode == EditMode::Page)
+        {
+            // At least one of the selected pages has to contain a title
+            // presentation objects in order to enable the summary page menu
+            // entry.
+            model::PageEnumeration aSelectedPages (
+                model::PageEnumerationProvider::CreateSelectedPagesEnumeration(
+                    mrSlideSorter.GetModel()));
+            while (aSelectedPages.HasMoreElements())
+            {
+                SdPage* pPage = aSelectedPages.GetNextElement()->GetPage();
+                SdrObject* pObj = pPage->GetPresObj(PresObjKind::Title);
+
+                if (pObj!=nullptr && !pObj->IsEmptyPresObj())
+                    bDisable = false;
+            }
+        }
+        if (bDisable)
+            rSet.DisableItem (SID_SUMMARY_PAGE);
+    }
+
+    // starting of presentation possible?
+    if( SfxItemState::DEFAULT == rSet.GetItemState( SID_PRESENTATION ) ||
+        SfxItemState::DEFAULT == rSet.GetItemState( SID_REHEARSE_TIMINGS ) )
+    {
+        bool bDisable = true;
+        model::PageEnumeration aAllPages (
+            model::PageEnumerationProvider::CreateAllPagesEnumeration(mrSlideSorter.GetModel()));
+        while (aAllPages.HasMoreElements())
+        {
+            SdPage* pPage = aAllPages.GetNextElement()->GetPage();
+
+            if( !pPage->IsExcluded() )
+                bDisable = false;
+        }
+        if( bDisable || pDocShell->IsPreview())
+        {
+            rSet.DisableItem( SID_PRESENTATION );
+            rSet.DisableItem( SID_REHEARSE_TIMINGS );
+        }
+    }
+
+    // Disable the rename slots when there are no or more than one slides/master
+    // pages selected; disable the duplicate slot when there are no slides
+    // selected:
+    if (rSet.GetItemState(SID_RENAMEPAGE) == SfxItemState::DEFAULT
+        || rSet.GetItemState(SID_RENAME_MASTER_PAGE) == SfxItemState::DEFAULT
+        || rSet.GetItemState(SID_DUPLICATE_PAGE) == SfxItemState::DEFAULT)
+    {
+        int n = mrSlideSorter.GetController().GetPageSelector()
+            .GetSelectedPageCount();
+        if (n != 1)
+        {
+            rSet.DisableItem(SID_RENAMEPAGE);
+            rSet.DisableItem(SID_RENAME_MASTER_PAGE);
+        }
+        if (n == 0)
+        {
+            rSet.DisableItem(SID_DUPLICATE_PAGE);
+        }
+    }
+
+    if (rSet.GetItemState(SID_HIDE_SLIDE) == SfxItemState::DEFAULT
+        || rSet.GetItemState(SID_SHOW_SLIDE)  == SfxItemState::DEFAULT)
+    {
+        model::PageEnumeration aSelectedPages (
+            model::PageEnumerationProvider::CreateSelectedPagesEnumeration(
+                mrSlideSorter.GetModel()));
+        const SlideExclusionState eState (GetSlideExclusionState(aSelectedPages));
+        switch (eState)
+        {
+            case MIXED:
+                // Show both entries.
+                break;
+
+            case EXCLUDED:
+                rSet.DisableItem(SID_HIDE_SLIDE);
+                break;
+
+            case INCLUDED:
+                rSet.DisableItem(SID_SHOW_SLIDE);
+                break;
+
+            case UNDEFINED:
+                rSet.DisableItem(SID_HIDE_SLIDE);
+                rSet.DisableItem(SID_SHOW_SLIDE);
+                break;
+        }
+    }
+
+    if (eEditMode == EditMode::MasterPage)
+    {
+        // Disable some slots when in master page mode.
+        rSet.DisableItem(SID_ASSIGN_LAYOUT);
+        rSet.DisableItem(SID_INSERTPAGE);
+
+        if (rSet.GetItemState(SID_DUPLICATE_PAGE) == SfxItemState::DEFAULT)
+            rSet.DisableItem(SID_DUPLICATE_PAGE);
+    }
+}
+
+void SlotManager::GetClipboardState ( SfxItemSet& rSet)
+{
+    SdTransferable* pTransferClip = SD_MOD()->pTransferClip;
+
+    if (rSet.GetItemState(SID_PASTE)  == SfxItemState::DEFAULT
+        || rSet.GetItemState(SID_PASTE_SPECIAL)  == SfxItemState::DEFAULT)
+    {
+        // no own clipboard data?
+        if ( !pTransferClip || !pTransferClip->GetDocShell().is() )
+        {
+            rSet.DisableItem(SID_PASTE);
+            rSet.DisableItem(SID_PASTE_SPECIAL);
+        }
+        else
+        {
+            SfxObjectShell* pTransferDocShell = pTransferClip->GetDocShell().get();
+
+            if( !pTransferDocShell || static_cast<DrawDocShell*>(pTransferDocShell)->GetDoc()->GetPageCount() <= 1 )
+            {
+                bool bIsPastingSupported (false);
+
+                // No or just one page.  Check if there is anything that can be
+                // pasted via a DrawViewShell.
+                ViewShellBase* pBase = mrSlideSorter.GetViewShellBase();
+                if (pBase != nullptr)
+                {
+                    std::shared_ptr<DrawViewShell> pDrawViewShell (
+                        std::dynamic_pointer_cast<DrawViewShell>(pBase->GetMainViewShell()));
+                    if (pDrawViewShell != nullptr)
+                    {
+                        TransferableDataHelper aDataHelper (
+                            TransferableDataHelper::CreateFromSystemClipboard(
+                                pDrawViewShell->GetActiveWindow()));
+                        if (aDataHelper.GetFormatCount() > 0)
+                            bIsPastingSupported = true;
+                    }
+                }
+
+                if ( ! bIsPastingSupported)
+                {
+                    rSet.DisableItem(SID_PASTE);
+                    rSet.DisableItem(SID_PASTE_SPECIAL);
+                }
+            }
+        }
+    }
+
+    // Cut, copy and paste of master pages is not yet implemented properly
+    if (rSet.GetItemState(SID_COPY) == SfxItemState::DEFAULT
+        || rSet.GetItemState(SID_PASTE)  == SfxItemState::DEFAULT
+        || rSet.GetItemState(SID_PASTE_SPECIAL)  == SfxItemState::DEFAULT
+        || rSet.GetItemState(SID_CUT)  == SfxItemState::DEFAULT)
+    {
+        if (mrSlideSorter.GetModel().GetEditMode() == EditMode::MasterPage)
+        {
+            if (rSet.GetItemState(SID_CUT) == SfxItemState::DEFAULT)
+                rSet.DisableItem(SID_CUT);
+            if (rSet.GetItemState(SID_COPY) == SfxItemState::DEFAULT)
+                rSet.DisableItem(SID_COPY);
+            if (rSet.GetItemState(SID_PASTE) == SfxItemState::DEFAULT)
+                rSet.DisableItem(SID_PASTE);
+            if (rSet.GetItemState(SID_PASTE_SPECIAL) == SfxItemState::DEFAULT)
+                rSet.DisableItem(SID_PASTE_SPECIAL);
+        }
+    }
+
+    ViewShellBase* pBase = mrSlideSorter.GetViewShellBase();
+    if (pBase && pBase->GetObjectShell()->isContentExtractionLocked())
+    {
+        rSet.DisableItem(SID_COPY);
+        rSet.DisableItem(SID_CUT);
+    }
+
+    // Cut, copy, and delete page are disabled when there is no selection.
+    if (!(rSet.GetItemState(SID_CUT) == SfxItemState::DEFAULT
+        || rSet.GetItemState(SID_COPY)  == SfxItemState::DEFAULT
+        || rSet.GetItemState(SID_DELETE) == SfxItemState::DEFAULT
+        || rSet.GetItemState(SID_DELETE_PAGE) == SfxItemState::DEFAULT
+        || rSet.GetItemState(SID_DELETE_MASTER_PAGE) == SfxItemState::DEFAULT))
+        return;
+
+    model::PageEnumeration aSelectedPages (
+        model::PageEnumerationProvider::CreateSelectedPagesEnumeration(
+            mrSlideSorter.GetModel()));
+
+    // For copy to work we have to have at least one selected page.
+    if ( ! aSelectedPages.HasMoreElements())
+        rSet.DisableItem(SID_COPY);
+
+    bool bDisable = false;
+    // The operations that lead to the deletion of a page are valid if
+    // a) there is at least one selected page
+    // b) deleting the selected pages leaves at least one page in the
+    // document
+    // c) selected master pages must not be used by slides.
+
+    // Test a).
+    if ( ! aSelectedPages.HasMoreElements())
+        bDisable = true;
+    // Test b): Count the number of selected pages.  It has to be less
+    // than the number of all pages.
+    else if (mrSlideSorter.GetController().GetPageSelector().GetSelectedPageCount()
+        >= mrSlideSorter.GetController().GetPageSelector().GetPageCount())
+        bDisable = true;
+    // Test c): Iterate over the selected pages and look for a master
+    // page that is used by at least one page.
+    else while (aSelectedPages.HasMoreElements())
+    {
+        SdPage* pPage = aSelectedPages.GetNextElement()->GetPage();
+        int nUseCount (mrSlideSorter.GetModel().GetDocument()
+            ->GetMasterPageUserCount(pPage));
+        if (nUseCount > 0)
+        {
+            bDisable = true;
+            break;
+        }
+    }
+
+    if (bDisable)
+    {
+        rSet.DisableItem(SID_CUT);
+        rSet.DisableItem(SID_DELETE_PAGE);
+        rSet.DisableItem(SID_DELETE_MASTER_PAGE);
+    }
+}
+
+void SlotManager::GetStatusBarState (SfxItemSet& rSet)
+{
+    // page view and layout
+    SdPage* pPage      = nullptr;
+    sal_uInt16 nSelectedPages = mrSlideSorter.GetController().GetPageSelector().GetSelectedPageCount();
+
+    //Set number of slides
+    if (nSelectedPages > 0)
+    {
+        model::PageEnumeration aSelectedPages (
+            model::PageEnumerationProvider::CreateSelectedPagesEnumeration(
+                mrSlideSorter.GetModel()));
+        model::SharedPageDescriptor pDescriptor (aSelectedPages.GetNextElement());
+        OUString aPageStr;
+        if (pDescriptor)
+        {
+            pPage = pDescriptor->GetPage();
+            sal_uInt16 nFirstPage = (pPage->GetPageNum()/2) + 1;
+            sal_Int32 nPageCount = mrSlideSorter.GetModel().GetPageCount();
+            sal_Int32 nActivePageCount = static_cast<sal_Int32>(mrSlideSorter.GetModel().GetDocument()->GetActiveSdPageCount());
+
+            aPageStr = (nPageCount == nActivePageCount) ? SdResId(STR_SD_PAGE_COUNT) : SdResId(STR_SD_PAGE_COUNT_CUSTOM);
+
+            aPageStr = aPageStr.replaceFirst("%1", OUString::number(nFirstPage));
+            aPageStr = aPageStr.replaceFirst("%2", OUString::number(nPageCount));
+            if(nPageCount != nActivePageCount)
+                aPageStr = aPageStr.replaceFirst("%3", OUString::number(nActivePageCount));
+        }
+        rSet.Put( SfxStringItem( SID_STATUS_PAGE, aPageStr ) );
+    }
+    //Set layout
+    if (nSelectedPages == 1 && pPage != nullptr)
+    {
+        SdPage* pFirstPage = pPage;
+        OUString aLayoutStr = pFirstPage->GetLayoutName();
+        sal_Int32 nIndex = aLayoutStr.indexOf( SD_LT_SEPARATOR );
+        if( nIndex != -1 )
+            aLayoutStr = aLayoutStr.copy(0, nIndex);
+        rSet.Put( SfxStringItem( SID_STATUS_LAYOUT, aLayoutStr ) );
+    }
+    //Scale value
+    const Fraction& aUIScale = mrSlideSorter.GetModel().GetDocument()->GetUIScale();
+    OUString aString = OUString::number(aUIScale.GetNumerator()) +
+        ":" + OUString::number(aUIScale.GetDenominator());
+    rSet.Put( SfxStringItem( SID_SCALE, aString ) );
+}
+
+void SlotManager::RenameSlide(const SfxRequest& rRequest)
+{
+    View* pDrView = &mrSlideSorter.GetView();
+
+    if ( pDrView->IsTextEdit() )
+    {
+        pDrView->SdrEndTextEdit();
+    }
+
+    SdPage* pSelectedPage = nullptr;
+    model::PageEnumeration aSelectedPages (
+            model::PageEnumerationProvider::CreateSelectedPagesEnumeration(
+                mrSlideSorter.GetModel()));
+    if (aSelectedPages.HasMoreElements())
+        pSelectedPage = aSelectedPages.GetNextElement()->GetPage();
+    if (pSelectedPage == nullptr)
+        return;
+
+    // tdf#107183 Set different dialog titles when renaming
+    // master slides or normal ones
+    OUString aTitle;
+    if( rRequest.GetSlot() == SID_RENAME_MASTER_PAGE )
+        aTitle = SdResId( STR_TITLE_RENAMEMASTER );
+    else if (pDrView->GetDoc().GetDocumentType() == DocumentType::Draw)
+        aTitle = SdResId( STR_TITLE_RENAMEPAGE );
+    else
+        aTitle = SdResId( STR_TITLE_RENAMESLIDE );
+
+    OUString aDescr( SdResId( STR_DESC_RENAMESLIDE ) );
+    OUString aPageName = pSelectedPage->GetName();
+
+    if(rRequest.GetArgs())
+    {
+       OUString aName = rRequest.GetArgs()->GetItem<const SfxStringItem>(SID_RENAMEPAGE)->GetValue();
+
+       bool bResult =  RenameSlideFromDrawViewShell(pSelectedPage->GetPageNum()/2, aName );
+       DBG_ASSERT( bResult, "Couldn't rename slide or page" );
+    }
+    else
+    {
+        SvxAbstractDialogFactory* pFact = SvxAbstractDialogFactory::Create();
+        vcl::Window* pWin = mrSlideSorter.GetContentWindow();
+        ScopedVclPtr<AbstractSvxNameDialog> aNameDlg(pFact->CreateSvxNameDialog(
+                pWin ? pWin->GetFrameWeld() : nullptr,
+                aPageName, aDescr));
+        OUString aOldName;
+        aNameDlg->GetName( aOldName );
+        aNameDlg->SetText( aTitle );
+        aNameDlg->SetCheckNameHdl( LINK( this, SlotManager, RenameSlideHdl ), true );
+        aNameDlg->SetCheckNameTooltipHdl( LINK( this, SlotManager, RenameSlideTooltipHdl ) );
+        aNameDlg->SetEditHelpId( HID_SD_NAMEDIALOG_PAGE );
+
+        if( aNameDlg->Execute() == RET_OK )
+        {
+            OUString aNewName;
+            aNameDlg->GetName( aNewName );
+            if (aNewName != aPageName)
+            {
+                bool bResult =
+                        RenameSlideFromDrawViewShell(
+                          pSelectedPage->GetPageNum()/2, aNewName );
+                DBG_ASSERT( bResult, "Couldn't rename slide or page" );
+            }
+        }
+        OUString aNewName;
+        aNameDlg->GetName( aNewName );
+        collectUIInformation({{"OldName", aOldName}, {"NewName", aNewName}}, "RENAME");
+        aNameDlg.disposeAndClear();
+    }
+    // Tell the slide sorter about the name change (necessary for
+    // accessibility.)
+    mrSlideSorter.GetController().PageNameHasChanged(
+            (pSelectedPage->GetPageNum()-1)/2, aPageName);
+}
+
+IMPL_LINK(SlotManager, RenameSlideHdl, AbstractSvxNameDialog&, rDialog, bool)
+{
+    OUString aNewName;
+    rDialog.GetName( aNewName );
+
+    model::SharedPageDescriptor pDescriptor (
+        mrSlideSorter.GetController().GetCurrentSlideManager()->GetCurrentSlide());
+    SdPage* pCurrentPage = nullptr;
+    if (pDescriptor)
+        pCurrentPage = pDescriptor->GetPage();
+
+    return (pCurrentPage!=nullptr && aNewName == pCurrentPage->GetName())
+        || (mrSlideSorter.GetViewShell()
+            && mrSlideSorter.GetViewShell()->GetDocSh()->IsNewPageNameValid( aNewName ) );
+}
+
+IMPL_STATIC_LINK_NOARG(SlotManager, RenameSlideTooltipHdl, AbstractSvxNameDialog&, OUString)
+{
+    return SdResId(STR_TOOLTIP_RENAME);
+}
+
+bool SlotManager::RenameSlideFromDrawViewShell( sal_uInt16 nPageId, const OUString & rName  )
+{
+    bool   bOutDummy;
+    SdDrawDocument* pDocument = mrSlideSorter.GetModel().GetDocument();
+    if( pDocument->GetPageByName( rName, bOutDummy ) != SDRPAGE_NOTFOUND )
+        return false;
+
+    SdPage* pPageToRename = nullptr;
+
+    SfxUndoManager* pManager = pDocument->GetDocSh()->GetUndoManager();
+
+    if( mrSlideSorter.GetModel().GetEditMode() == EditMode::Page )
+    {
+        model::SharedPageDescriptor pDescriptor (
+            mrSlideSorter.GetController().GetCurrentSlideManager()->GetCurrentSlide());
+        if (pDescriptor)
+            pPageToRename = pDescriptor->GetPage();
+
+        if (pPageToRename != nullptr)
+        {
+            // Undo
+            SdPage* pUndoPage = pPageToRename;
+            SdrLayerAdmin &  rLayerAdmin = pDocument->GetLayerAdmin();
+            SdrLayerID nBackground = rLayerAdmin.GetLayerID(sUNO_LayerName_background);
+            SdrLayerID nBgObj = rLayerAdmin.GetLayerID(sUNO_LayerName_background_objects);
+            SdrLayerIDSet aVisibleLayers = pPageToRename->TRG_GetMasterPageVisibleLayers();
+
+            // (#67720#)
+            pManager->AddUndoAction(
+                std::make_unique<ModifyPageUndoAction>(
+                    pDocument, pUndoPage, rName, pUndoPage->GetAutoLayout(),
+                    aVisibleLayers.IsSet( nBackground ),
+                    aVisibleLayers.IsSet( nBgObj )));
+
+            // rename
+            pPageToRename->SetName( rName );
+
+            // also rename notes-page
+            SdPage* pNotesPage = pDocument->GetSdPage( nPageId, PageKind::Notes );
+            if (pNotesPage != nullptr)
+                pNotesPage->SetName (rName);
+        }
+    }
+    else
+    {
+        // rename MasterPage -> rename LayoutTemplate
+        pPageToRename = pDocument->GetMasterSdPage( nPageId, PageKind::Standard );
+        if (pPageToRename != nullptr)
+        {
+            const OUString aOldLayoutName( pPageToRename->GetLayoutName() );
+            pManager->AddUndoAction( std::make_unique<RenameLayoutTemplateUndoAction>( pDocument, aOldLayoutName, rName ) );
+            pDocument->RenameLayoutTemplate( aOldLayoutName, rName );
+        }
+    }
+
+    bool bSuccess = pPageToRename!=nullptr && ( rName == pPageToRename->GetName() );
+
+    if( bSuccess )
+    {
+        // user edited page names may be changed by the page so update control
+        //        aTabControl.SetPageText( nPageId, rName );
+
+        // set document to modified state
+        pDocument->SetChanged();
+
+        // inform navigator about change
+        if (mrSlideSorter.GetViewShell() && mrSlideSorter.GetViewShell()->GetViewFrame())
+            mrSlideSorter.GetViewShell()->GetViewFrame()->GetBindings().Invalidate(
+                        SID_NAVIGATOR_STATE, true);
+    }
+
+    return bSuccess;
+}
+
+/** Insert a slide.  The insertion position depends on a) the selection and
+    b) the mouse position when there is no selection.
+
+    When there is a selection then insertion takes place after the last
+    slide of the selection.  For this to work all but the last selected
+    slide are deselected first.
+
+    Otherwise, when there is no selection but the insertion marker is visible
+    the slide is inserted at that position.  The slide before that marker is
+    selected first.
+
+    When both the selection and the insertion marker are not visible--can
+    that happen?--the new slide is inserted after the last slide.
+*/
+void SlotManager::InsertSlide (SfxRequest& rRequest)
+{
+    const sal_Int32 nInsertionIndex (GetInsertionPosition());
+
+    PageSelector::BroadcastLock aBroadcastLock (mrSlideSorter);
+
+    SdPage* pNewPage = nullptr;
+    if (mrSlideSorter.GetModel().GetEditMode() == EditMode::Page)
+    {
+        SlideSorterViewShell* pShell = dynamic_cast<SlideSorterViewShell*>(
+            mrSlideSorter.GetViewShell());
+        if (pShell != nullptr)
+        {
+            pNewPage = pShell->CreateOrDuplicatePage (
+                rRequest,
+                PageKind::Standard,
+                nInsertionIndex>=0
+                    ? mrSlideSorter.GetModel().GetPageDescriptor(nInsertionIndex)->GetPage()
+                        : nullptr);
+        }
+    }
+    else
+    {
+        // Use the API to create a new page.
+        SdDrawDocument* pDocument = mrSlideSorter.GetModel().GetDocument();
+        Reference<drawing::XMasterPagesSupplier> xMasterPagesSupplier (
+            pDocument->getUnoModel(), UNO_QUERY);
+        if (xMasterPagesSupplier.is())
+        {
+            Reference<drawing::XDrawPages> xMasterPages (
+                xMasterPagesSupplier->getMasterPages());
+            if (xMasterPages.is())
+            {
+                xMasterPages->insertNewByIndex (nInsertionIndex+1);
+
+                // Create shapes for the default layout.
+                pNewPage = pDocument->GetMasterSdPage(
+                    static_cast<sal_uInt16>(nInsertionIndex+1), PageKind::Standard);
+                pNewPage->CreateTitleAndLayout (true,true);
+            }
+        }
+    }
+    if (pNewPage == nullptr)
+        return;
+
+    // When a new page has been inserted then select it, make it the
+    // current page, and focus it.
+    view::SlideSorterView::DrawLock aDrawLock (mrSlideSorter);
+    PageSelector::UpdateLock aUpdateLock (mrSlideSorter);
+    mrSlideSorter.GetController().GetPageSelector().DeselectAllPages();
+    mrSlideSorter.GetController().GetPageSelector().SelectPage(pNewPage);
+    collectUIInformation({{"POS", OUString::number(nInsertionIndex + 2)}}, "Insert_New_Page_or_Slide");
+}
+
+void SlotManager::DuplicateSelectedSlides (SfxRequest& rRequest)
+{
+    // Create a list of the pages that are to be duplicated.  The process of
+    // duplication alters the selection.
+    sal_Int32 nInsertPosition (0);
+    ::std::vector<SdPage*> aPagesToDuplicate;
+    model::PageEnumeration aSelectedPages (
+        model::PageEnumerationProvider::CreateSelectedPagesEnumeration(mrSlideSorter.GetModel()));
+    while (aSelectedPages.HasMoreElements())
+    {
+        model::SharedPageDescriptor pDescriptor (aSelectedPages.GetNextElement());
+        if (pDescriptor && pDescriptor->GetPage())
+        {
+            aPagesToDuplicate.push_back(pDescriptor->GetPage());
+            nInsertPosition = pDescriptor->GetPage()->GetPageNum()+2;
+        }
+    }
+
+    // Duplicate the pages in aPagesToDuplicate and collect the newly
+    // created pages in aPagesToSelect.
+    const bool bUndo (aPagesToDuplicate.size()>1 && mrSlideSorter.GetView().IsUndoEnabled());
+    if (bUndo)
+        mrSlideSorter.GetView().BegUndo(SdResId(STR_INSERTPAGE));
+
+    ::std::vector<SdPage*> aPagesToSelect;
+    for(const auto& rpPage : aPagesToDuplicate)
+    {
+        aPagesToSelect.push_back(
+            mrSlideSorter.GetViewShell()->CreateOrDuplicatePage(
+                rRequest, PageKind::Standard, rpPage, nInsertPosition));
+        nInsertPosition += 2;
+    }
+    aPagesToDuplicate.clear();
+
+    if (bUndo)
+        mrSlideSorter.GetView().EndUndo();
+
+    // Set the selection to the pages in aPagesToSelect.
+    PageSelector& rSelector (mrSlideSorter.GetController().GetPageSelector());
+    rSelector.DeselectAllPages();
+    for (auto const& it: aPagesToSelect)
+    {
+        rSelector.SelectPage(it);
+    }
+
+    collectUIInformation({{"POS", OUString::number(nInsertPosition + 2)}}, "Duplicate");
+}
+
+void SlotManager::ChangeSlideExclusionState (
+    const model::SharedPageDescriptor& rpDescriptor,
+    const bool bExcludeSlide)
+{
+    if (rpDescriptor)
+    {
+        mrSlideSorter.GetView().SetState(
+            rpDescriptor,
+            model::PageDescriptor::ST_Excluded,
+            bExcludeSlide);
+    }
+    else
+    {
+        model::PageEnumeration aSelectedPages (
+            model::PageEnumerationProvider::CreateSelectedPagesEnumeration(
+                mrSlideSorter.GetModel()));
+        while (aSelectedPages.HasMoreElements())
+        {
+            model::SharedPageDescriptor pDescriptor (aSelectedPages.GetNextElement());
+            mrSlideSorter.GetView().SetState(
+                pDescriptor,
+                model::PageDescriptor::ST_Excluded,
+                bExcludeSlide);
+        }
+    }
+
+    SfxBindings& rBindings (mrSlideSorter.GetViewShell()->GetViewFrame()->GetBindings());
+    rBindings.Invalidate(SID_PRESENTATION);
+    rBindings.Invalidate(SID_REHEARSE_TIMINGS);
+    rBindings.Invalidate(SID_HIDE_SLIDE);
+    rBindings.Invalidate(SID_SHOW_SLIDE);
+    mrSlideSorter.GetModel().GetDocument()->SetChanged();
+}
+
+sal_Int32 SlotManager::GetInsertionPosition() const
+{
+    PageSelector& rSelector (mrSlideSorter.GetController().GetPageSelector());
+
+    // The insertion indicator is preferred.  After all the user explicitly
+    // used it to define the insertion position.
+    if (mrSlideSorter.GetController().GetInsertionIndicatorHandler()->IsActive())
+    {
+        // Select the page before the insertion indicator.
+        return mrSlideSorter.GetController().GetInsertionIndicatorHandler()->GetInsertionPageIndex()
+            - 1;
+    }
+
+    // Is there a stored insertion position?
+    else if (mrSlideSorter.GetController().GetSelectionManager()->GetInsertionPosition() >= 0)
+    {
+        return mrSlideSorter.GetController().GetSelectionManager()->GetInsertionPosition() - 1;
+    }
+
+    // Use the index of the last selected slide.
+    else if (rSelector.GetSelectedPageCount() > 0)
+    {
+        for (int nIndex=rSelector.GetPageCount()-1; nIndex>=0; --nIndex)
+            if (rSelector.IsPageSelected(nIndex))
+                return nIndex;
+
+        // We should never get here.
+        OSL_ASSERT(false);
+        return rSelector.GetPageCount() - 1;
+    }
+
+    // Select the last page when there is at least one page.
+    else if (rSelector.GetPageCount() > 0)
+    {
+        return rSelector.GetPageCount() - 1;
+    }
+
+    // Hope for the best that CreateOrDuplicatePage() can cope with an empty
+    // selection.
+    else
+    {
+        // We should never get here because there has to be at least one page.
+        OSL_ASSERT(false);
+        return -1;
+    }
+}
+
+void SlotManager::NotifyEditModeChange()
+{
+    SfxBindings& rBindings (mrSlideSorter.GetViewShell()->GetViewFrame()->GetBindings());
+    rBindings.Invalidate(SID_PRESENTATION);
+    rBindings.Invalidate(SID_INSERTPAGE);
+    rBindings.Invalidate(SID_DUPLICATE_PAGE);
+}
+
+namespace {
+
+SlideExclusionState GetSlideExclusionState (model::PageEnumeration& rPageSet)
+{
+    SlideExclusionState eState (UNDEFINED);
+
+    // Get toggle state of the selected pages.
+    while (rPageSet.HasMoreElements() && eState!=MIXED)
+    {
+        const bool bState = rPageSet.GetNextElement()->GetPage()->IsExcluded();
+        switch (eState)
+        {
+            case UNDEFINED:
+                // Use the first selected page to set the initial value.
+                eState = bState ? EXCLUDED : INCLUDED;
+                break;
+
+            case EXCLUDED:
+                // The pages before where all not part of the show,
+                // this one is.
+                if ( ! bState)
+                    eState = MIXED;
+                break;
+
+            case INCLUDED:
+                // The pages before where all part of the show,
+                // this one is not.
+                if (bState)
+                    eState = MIXED;
+                break;
+
+            default:
+                // No need to change anything.
+                break;
+        }
+    }
+
+    return eState;
+}
+
+} // end of anonymous namespace
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/controller/SlsTransferableData.cxx b/sd/source/ui/slidesorter/controller/SlsTransferableData.cxx
new file mode 100644
index 000000000..f4b89a5ab
--- /dev/null
+++ b/sd/source/ui/slidesorter/controller/SlsTransferableData.cxx
@@ -0,0 +1,86 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <controller/SlsTransferableData.hxx>
+
+#include <SlideSorterViewShell.hxx>
+
+namespace sd::slidesorter::controller {
+
+rtl::Reference<SdTransferable> TransferableData::CreateTransferable (
+    SdDrawDocument* pSrcDoc,
+    SlideSorterViewShell* pViewShell,
+    ::std::vector<Representative>&& rRepresentatives)
+{
+    rtl::Reference<SdTransferable> pTransferable = new SdTransferable (pSrcDoc, nullptr, false/*bInitOnGetData*/);
+    auto pData = std::make_shared<TransferableData>(pViewShell, std::move(rRepresentatives));
+    pTransferable->AddUserData(pData);
+    return pTransferable;
+}
+
+std::shared_ptr<TransferableData> TransferableData::GetFromTransferable (const SdTransferable* pTransferable)
+{
+    if (pTransferable)
+    {
+        for (sal_Int32 nIndex=0,nCount=pTransferable->GetUserDataCount(); nIndex<nCount; ++nIndex)
+        {
+            std::shared_ptr<TransferableData> xData =
+                std::dynamic_pointer_cast<TransferableData>(pTransferable->GetUserData(nIndex));
+            if (xData)
+                return xData;
+        }
+    }
+    return std::shared_ptr<TransferableData>();
+}
+
+TransferableData::TransferableData (
+    SlideSorterViewShell* pViewShell,
+    ::std::vector<Representative>&& rRepresentatives)
+    : mpViewShell(pViewShell),
+      maRepresentatives(std::move(rRepresentatives))
+{
+    if (mpViewShell != nullptr)
+        StartListening(*mpViewShell);
+}
+
+TransferableData::~TransferableData()
+{
+    if (mpViewShell != nullptr)
+        EndListening(*mpViewShell);
+}
+
+void TransferableData::Notify (SfxBroadcaster&, const SfxHint& rHint)
+{
+    if (mpViewShell)
+    {
+        if (rHint.GetId() == SfxHintId::Dying)
+        {
+            // This hint may come either from the ViewShell or from the
+            // document (registered by SdTransferable).  We do not know
+            // which but both are sufficient to disconnect from the
+            // ViewShell.
+            EndListening(*mpViewShell);
+            mpViewShell = nullptr;
+        }
+    }
+}
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/controller/SlsVisibleAreaManager.cxx b/sd/source/ui/slidesorter/controller/SlsVisibleAreaManager.cxx
new file mode 100644
index 000000000..6f85f362d
--- /dev/null
+++ b/sd/source/ui/slidesorter/controller/SlsVisibleAreaManager.cxx
@@ -0,0 +1,234 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <sal/config.h>
+
+#include <controller/SlsVisibleAreaManager.hxx>
+#include <controller/SlideSorterController.hxx>
+#include <controller/SlsAnimationFunction.hxx>
+#include <controller/SlsScrollBarManager.hxx>
+#include <controller/SlsCurrentSlideManager.hxx>
+#include <Window.hxx>
+#include <SlideSorter.hxx>
+#include <view/SlideSorterView.hxx>
+
+namespace sd::slidesorter::controller {
+
+namespace {
+    class VisibleAreaScroller
+    {
+    public:
+        VisibleAreaScroller (
+            SlideSorter& rSlideSorter,
+            const Point& rStart,
+            const Point& rEnd);
+        void operator() (const double nValue);
+    private:
+        SlideSorter& mrSlideSorter;
+        Point maStart;
+        const Point maEnd;
+        const ::std::function<double (double)> maAccelerationFunction;
+    };
+
+} // end of anonymous namespace
+
+VisibleAreaManager::VisibleAreaManager (SlideSorter& rSlideSorter)
+    : mrSlideSorter(rSlideSorter),
+      mbIsCurrentSlideTrackingActive(true),
+      mnDisableCount(0)
+{
+}
+
+VisibleAreaManager::~VisibleAreaManager()
+{
+}
+
+void VisibleAreaManager::ActivateCurrentSlideTracking()
+{
+    mbIsCurrentSlideTrackingActive = true;
+}
+
+void VisibleAreaManager::DeactivateCurrentSlideTracking()
+{
+    mbIsCurrentSlideTrackingActive = false;
+}
+
+void VisibleAreaManager::RequestVisible (
+    const model::SharedPageDescriptor& rpDescriptor,
+    const bool bForce)
+{
+    if (!rpDescriptor)
+        return;
+
+    if (mnDisableCount == 0)
+    {
+        maVisibleRequests.push_back(
+            mrSlideSorter.GetView().GetLayouter().GetPageObjectBox(
+                rpDescriptor->GetPageIndex(),
+                true));
+    }
+    if (bForce && ! mbIsCurrentSlideTrackingActive)
+        ActivateCurrentSlideTracking();
+    MakeVisible();
+}
+
+void VisibleAreaManager::RequestCurrentSlideVisible()
+{
+    if (mbIsCurrentSlideTrackingActive && mnDisableCount==0)
+        RequestVisible(
+            mrSlideSorter.GetController().GetCurrentSlideManager()->GetCurrentSlide());
+}
+
+void VisibleAreaManager::MakeVisible()
+{
+    if (maVisibleRequests.empty())
+        return;
+
+    sd::Window *pWindow (mrSlideSorter.GetContentWindow().get());
+    if ( ! pWindow)
+        return;
+    const Point aCurrentTopLeft (pWindow->PixelToLogic(Point(0,0)));
+
+    const ::std::optional<Point> aNewVisibleTopLeft (GetRequestedTopLeft());
+    maVisibleRequests.clear();
+    if ( ! aNewVisibleTopLeft)
+        return;
+
+    maRequestedVisibleTopLeft = *aNewVisibleTopLeft;
+    VisibleAreaScroller aAnimation(
+        mrSlideSorter,
+        aCurrentTopLeft,
+        maRequestedVisibleTopLeft);
+    // Execute the animation at its final value.
+    aAnimation(1.0);
+}
+
+::std::optional<Point> VisibleAreaManager::GetRequestedTopLeft() const
+{
+    sd::Window *pWindow (mrSlideSorter.GetContentWindow().get());
+    if ( ! pWindow)
+        return ::std::optional<Point>();
+
+    // Get the currently visible area and the model area.
+    const ::tools::Rectangle aVisibleArea (pWindow->PixelToLogic(
+        ::tools::Rectangle(
+            Point(0,0),
+            pWindow->GetOutputSizePixel())));
+    const ::tools::Rectangle aModelArea (mrSlideSorter.GetView().GetModelArea());
+
+    sal_Int32 nVisibleTop (aVisibleArea.Top());
+    const sal_Int32 nVisibleWidth (aVisibleArea.GetWidth());
+    sal_Int32 nVisibleLeft (aVisibleArea.Left());
+    const sal_Int32 nVisibleHeight (aVisibleArea.GetHeight());
+
+    // Find the longest run of boxes whose union fits into the visible area.
+    for (const auto& rBox : maVisibleRequests)
+    {
+        if (nVisibleTop+nVisibleHeight <= rBox.Bottom())
+            nVisibleTop = rBox.Bottom()-nVisibleHeight;
+        if (nVisibleTop > rBox.Top())
+            nVisibleTop = rBox.Top();
+
+        if (nVisibleLeft+nVisibleWidth <= rBox.Right())
+            nVisibleLeft = rBox.Right()-nVisibleWidth;
+        if (nVisibleLeft > rBox.Left())
+            nVisibleLeft = rBox.Left();
+
+        // Make sure the visible area does not move outside the model area.
+        if (nVisibleTop + nVisibleHeight > aModelArea.Bottom())
+            nVisibleTop = aModelArea.Bottom() - nVisibleHeight;
+        if (nVisibleTop < aModelArea.Top())
+            nVisibleTop = aModelArea.Top();
+
+        if (nVisibleLeft + nVisibleWidth > aModelArea.Right())
+            nVisibleLeft = aModelArea.Right() - nVisibleWidth;
+        if (nVisibleLeft < aModelArea.Left())
+            nVisibleLeft = aModelArea.Left();
+    }
+
+    const Point aRequestedTopLeft (nVisibleLeft, nVisibleTop);
+    if (aRequestedTopLeft == aVisibleArea.TopLeft())
+        return ::std::optional<Point>();
+    else
+        return ::std::optional<Point>(aRequestedTopLeft);
+}
+
+//===== VisibleAreaManager::TemporaryDisabler =================================
+
+VisibleAreaManager::TemporaryDisabler::TemporaryDisabler (SlideSorter const & rSlideSorter)
+    : mrVisibleAreaManager(rSlideSorter.GetController().GetVisibleAreaManager())
+{
+    ++mrVisibleAreaManager.mnDisableCount;
+}
+
+VisibleAreaManager::TemporaryDisabler::~TemporaryDisabler()
+{
+    --mrVisibleAreaManager.mnDisableCount;
+}
+
+//===== VerticalVisibleAreaScroller ===========================================
+
+namespace {
+
+const sal_Int32 gnMaxScrollDistance = 300;
+
+VisibleAreaScroller::VisibleAreaScroller (
+    SlideSorter& rSlideSorter,
+    const Point& rStart,
+    const Point& rEnd)
+    : mrSlideSorter(rSlideSorter),
+      maStart(rStart),
+      maEnd(rEnd),
+      maAccelerationFunction(
+          controller::AnimationParametricFunction(
+              controller::AnimationBezierFunction (0.1,0.6)))
+{
+    // When the distance to scroll is larger than a threshold then first
+    // jump to within this distance of the final value and start the
+    // animation from there.
+    if (std::abs(rStart.X()-rEnd.X()) > gnMaxScrollDistance)
+    {
+        if (rStart.X() < rEnd.X())
+            maStart.setX( rEnd.X()-gnMaxScrollDistance );
+        else
+            maStart.setX( rEnd.X()+gnMaxScrollDistance );
+    }
+    if (std::abs(rStart.Y()-rEnd.Y()) > gnMaxScrollDistance)
+    {
+        if (rStart.Y() < rEnd.Y())
+            maStart.setY( rEnd.Y()-gnMaxScrollDistance );
+        else
+            maStart.setY( rEnd.Y()+gnMaxScrollDistance );
+    }
+}
+
+void VisibleAreaScroller::operator() (const double nTime)
+{
+    const double nLocalTime (maAccelerationFunction(nTime));
+    mrSlideSorter.GetController().GetScrollBarManager().SetTopLeft(
+        Point(
+            sal_Int32(0.5 + maStart.X() * (1.0 - nLocalTime) + maEnd.X() * nLocalTime),
+            sal_Int32 (0.5 + maStart.Y() * (1.0 - nLocalTime) + maEnd.Y() * nLocalTime)));
+}
+
+} // end of anonymous namespace
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/cache/SlsCacheContext.hxx b/sd/source/ui/slidesorter/inc/cache/SlsCacheContext.hxx
new file mode 100644
index 000000000..12993fdbb
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/cache/SlsCacheContext.hxx
@@ -0,0 +1,98 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <sal/types.h>
+#include <com/sun/star/uno/Reference.hxx>
+#include <memory>
+#include <vector>
+
+namespace com::sun::star::uno
+{
+class XInterface;
+}
+
+class SdrPage;
+
+namespace sd::slidesorter::cache
+{
+typedef const SdrPage* CacheKey;
+
+/** This interface allows the individualisation of different instances of
+    the PreviewCache.
+*/
+class CacheContext
+{
+public:
+    virtual ~CacheContext() {}
+
+    /** This method is called when the asynchronous creation of a preview
+        has been finished.
+        @param aKey
+            The key of the page for which the preview has been created.
+    */
+    virtual void NotifyPreviewCreation(CacheKey aKey) = 0;
+
+    /** Called to determine whether the system is idle and a preview can be
+        created without annoying the user.
+    */
+    virtual bool IsIdle() = 0;
+
+    /** This method is used to determine whether a page is currently visible
+        or not.  It is called when the cache becomes too large and some
+        previews have to be released or scaled down.
+    */
+    virtual bool IsVisible(CacheKey aKey) = 0;
+
+    /** Return the page associated with the given key.  Note that different
+        keys may map to a single page (this may be the case with custom
+        slide shows.)
+    */
+    virtual const SdrPage* GetPage(CacheKey aKey) = 0;
+
+    /** This method is used when the request queue is filled.  It asks for
+        the list of visible entries and maybe for the list of not visible
+        entries and creates preview creation requests for them.
+        @param bVisible
+            When this is <FALSE/> then the implementation can decide whether
+            to allow rendering of previews that are not visible (ahead of
+            time). When not then return an empty pointer or an empty vector.
+    */
+    virtual std::shared_ptr<std::vector<CacheKey>> GetEntryList(bool bVisible) = 0;
+
+    /** Return the priority that defines the order in which previews are
+        created for different keys/pages.  Typically the visible pages come
+        first, then top-down, left-to-right.
+    */
+    virtual sal_Int32 GetPriority(CacheKey aKey) = 0;
+
+    /** Return the model to which the pages belong for which the called
+        cache manages the previews.  Different caches that belong to the
+        same model but have different preview sizes may access previews of
+        each other in order to create fast previews of the previews.
+    */
+    virtual css::uno::Reference<css::uno::XInterface> GetModel() = 0;
+};
+
+typedef std::shared_ptr<CacheContext> SharedCacheContext;
+
+} // end of namespace ::sd::slidesorter::cache
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/cache/SlsPageCache.hxx b/sd/source/ui/slidesorter/inc/cache/SlsPageCache.hxx
new file mode 100644
index 000000000..4fb596195
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/cache/SlsPageCache.hxx
@@ -0,0 +1,141 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <cache/SlsCacheContext.hxx>
+#include <vcl/bitmapex.hxx>
+#include <memory>
+
+class Size;
+
+namespace sd::slidesorter::cache
+{
+class GenericPageCache;
+
+/** The page cache is responsible for the creation and storage of preview
+    bitmaps of pages that are shown by the slide sorter.
+
+    <p>Bitmaps for previews and a cache are used to speed up the display
+    (painting) of the slide sorter.  But, of course, we have to limit this
+    time-space-tradeoff by limiting the amount of space that can be use to
+    store bitmaps.</p>
+
+    <p>There are several strategies employed by this class to shorten the
+    perceived time that is used to paint the slide sorter:
+    <ul>
+    <li>Rendering pages ahead of time.  Additionally to rendering the
+    visible slides we try to render part or all of the slides that are not
+    (yet) visible.  This, of course, makes sense only when the computer is
+    otherwise idle while doing that.</li>
+    <li>When the size of the slides on the screen changes we mark the
+    bitmaps as needing an update but use them while the new bitmap in the
+    correct size is not available.</li>
+    <li>Give the UI the chance to handle user events between the rendering
+    of differe slides.</li>
+    <li>Limit the amount of space that may be used for storing preview
+    bitmaps and throw.</li>
+    </p>
+
+    <p>There is another somewhat similar methods for requesting new previews:
+    GetPreviewBitmap() schedules a re-rendering (when necessary) and
+    returns the preview what is currently available, either as a preview of
+    the preview or, when nothing has changed since the last call, as the
+    final thing.
+    </p>
+*/
+class PageCache
+{
+public:
+    /** The page cache is created with a reference to the slide sorter so
+        that it has access to both the view and the model and so can fill
+        itself with requests for all or just the visible pages.
+
+        It is the task of the PageCacheManager to create new objects of this
+        class.
+    */
+    PageCache(const Size& rPreviewSize, const bool bDoSuperSampling,
+              const SharedCacheContext& rpCacheContext);
+
+    ~PageCache();
+
+    void ChangeSize(const Size& rPreviewSize, const bool bDoSuperSampling);
+
+    /** Request a preview bitmap for the specified page object in the
+        specified size.  The returned bitmap may be a preview of the
+        preview, i.e. either a scaled (up or down) version of a previous
+        preview (of the wrong size) or an empty bitmap.  In this case a
+        request for the generation of a new preview is created and inserted
+        into the request queue.  When the preview is available in the right
+        size the page shape will be told to paint itself again.  When it
+        then calls this method again if receives the correctly sized preview
+        bitmap.
+        @param rRequestData
+            This data is used to determine the preview.
+        @param bResize
+            When <TRUE/> then when the available bitmap has not the
+            requested size, it is scaled before it is returned.  When
+            <FALSE/> then the bitmap is returned in the wrong size and it is
+            the task of the caller to scale it.
+        @return
+            Returns a bitmap that is either empty, contains a scaled (up or
+            down) version or is the requested bitmap.
+    */
+    BitmapEx GetPreviewBitmap(const CacheKey aKey, const bool bResize);
+
+    BitmapEx GetMarkedPreviewBitmap(const CacheKey aKey);
+    void SetMarkedPreviewBitmap(const CacheKey aKey, const BitmapEx& rBitmap);
+
+    /** When the requested preview bitmap does not yet exist or is not
+        up-to-date then the rendering of one is scheduled.  Otherwise this
+        method does nothing.
+    */
+    void RequestPreviewBitmap(const CacheKey aKey);
+
+    /** Tell the cache that the bitmap associated with the given request
+        data is not up-to-date anymore.  This will invalidate all previews
+        in other caches that represent the same page as well.
+        A new preview is requested and will lead
+        eventually to a repaint of the associated page object.
+    */
+    void InvalidatePreviewBitmap(const CacheKey aKey);
+
+    /** Call this method when all preview bitmaps have to be generated anew.
+        This is the case when the size of the page objects on the screen has
+        changed or when the model has changed.
+    */
+    void InvalidateCache();
+
+    /** With the precious flag you can control whether a bitmap can be
+        removed or reduced in size to make room for other bitmaps or is so
+        precious that it will not touched.  A typical use is to set the
+        precious flag for exactly the visible pages.
+    */
+    void SetPreciousFlag(const CacheKey aKey, const bool bIsPrecious);
+
+    void Pause();
+    void Resume();
+
+private:
+    std::unique_ptr<GenericPageCache> mpImplementation;
+};
+
+} // end of namespace ::sd::slidesorter::cache
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/cache/SlsPageCacheManager.hxx b/sd/source/ui/slidesorter/inc/cache/SlsPageCacheManager.hxx
new file mode 100644
index 000000000..eaddea5b2
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/cache/SlsPageCacheManager.hxx
@@ -0,0 +1,155 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <sal/types.h>
+#include <com/sun/star/uno/XInterface.hpp>
+#include <memory>
+#include <vector>
+
+class Size;
+class SdrPage;
+
+namespace sd::slidesorter::cache {
+
+class BitmapCache;
+
+/** Provide and manage the preview bitmap caches for all slide sorter
+    instances.  There is one cache per active slide sorter plus a small
+    number of caches that are no longer in use.  The later are kept to speed
+    up the switching between views.
+*/
+class PageCacheManager
+{
+public:
+    typedef std::vector< std::pair<Size, std::shared_ptr<BitmapCache> > > BestFittingPageCaches;
+    typedef css::uno::Reference<css::uno::XInterface> DocumentKey;
+
+    /** Return the one instance of the PageCacheManager class.
+    */
+    static std::shared_ptr<PageCacheManager> Instance();
+
+    /** Look up the cache for the given model in which the previews have the
+        specified size.  If no such cache exists, then one is created.  When
+        a new BitmapCache is created its Recycle() method is called with a
+        sorted list of existing caches from which the new one initialize its
+        previews.
+        @return
+            The returned cache lives as long as somebody keeps a shared
+            pointer and the ReleaseCache() method has not been called.
+    */
+    std::shared_ptr<BitmapCache> GetCache (
+        const  DocumentKey& pDocument,
+        const Size& rPreviewSize);
+
+    /** Tell the cache manager to release its own reference to the specified
+        cache.  After that the cache will live as long as the caller (and
+        maybe others) holds its reference.
+    */
+    void ReleaseCache (const std::shared_ptr<BitmapCache>& rpCache);
+
+    /** This is an information to the cache manager that the size of preview
+        bitmaps in the specified cache has changed.
+
+    */
+    std::shared_ptr<BitmapCache> ChangeSize (
+        const std::shared_ptr<BitmapCache>& rpCache,
+        const Size& rOldPreviewSize,
+        const Size& rNewPreviewSize);
+
+    /** Invalidate the preview bitmap for one slide that belongs to the
+        specified document.  The bitmaps for this slide in all caches are
+        marked as out-of-date and will be re-created when they are requested
+        the next time.
+    */
+    bool InvalidatePreviewBitmap (
+        const DocumentKey& pDocument,
+        const SdrPage* pPage);
+
+    /** Invalidate the preview bitmaps for all slides that belong to the
+        specified document.  This is necessary after model changes that
+        affect e.g. page number fields.
+    */
+    void InvalidateAllPreviewBitmaps (const DocumentKey& pDocument);
+
+    /** Invalidate all the caches that are currently in use and destroy
+        those that are not.  This is used for example when the high contrast
+        mode is turned on or off.
+    */
+    void InvalidateAllCaches();
+
+    /** Call this method when a page has been deleted and its preview
+        is not needed anymore.
+    */
+    void ReleasePreviewBitmap (const SdrPage* pPage);
+
+private:
+    /** Singleton instance of the cache manager.  Note that this is a weak
+        pointer.  The (implementation class of) ViewShellBase holds a
+        shared_ptr so that the cache manager has the same life time as the
+        ViewShellBase.
+    */
+    static std::weak_ptr<PageCacheManager> mpInstance;
+
+    /// List of active caches.
+    class PageCacheContainer;
+    std::unique_ptr<PageCacheContainer> mpPageCaches;
+
+    /// List of inactive, recently used caches.
+    class RecentlyUsedPageCaches;
+    std::unique_ptr<RecentlyUsedPageCaches> mpRecentlyUsedPageCaches;
+
+    /** The maximal number of recently used caches that are kept alive after
+        they have become inactive, i.e. after they are not used anymore by a
+        slide sorter.
+    */
+    static const sal_uInt32 mnMaximalRecentlyCacheCount = 2;
+
+    PageCacheManager();
+    ~PageCacheManager();
+
+    class Deleter;
+    friend class Deleter;
+
+    std::shared_ptr<BitmapCache> GetRecentlyUsedCache(
+        const DocumentKey& pDocument,
+        const Size& rSize);
+
+    /** Add the given cache to the list of recently used caches for the
+        document.  There is one such list per document.  Each least has at
+        most mnMaximalRecentlyCacheCount members.
+    */
+    void PutRecentlyUsedCache(
+        DocumentKey const & pDocument,
+        const Size& rPreviewSize,
+        const std::shared_ptr<BitmapCache>& rpCache);
+
+    /** This method is used internally to initialize a newly created
+        BitmapCache with already existing previews.
+    */
+    void Recycle (
+        const std::shared_ptr<BitmapCache>& rpCache,
+        const DocumentKey& pDocument,
+        const Size& rPreviewSize);
+};
+
+} // end of namespace ::sd::slidesorter::cache
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/controller/SlideSorterController.hxx b/sd/source/ui/slidesorter/inc/controller/SlideSorterController.hxx
new file mode 100644
index 000000000..10c2aa13e
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/controller/SlideSorterController.hxx
@@ -0,0 +1,327 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <model/SlsSharedPageDescriptor.hxx>
+#include <pres.hxx>
+
+#include <tools/link.hxx>
+#include <tools/gen.hxx>
+#include <rtl/ref.hxx>
+#include <rtl/ustring.hxx>
+
+#include <sddllapi.h>
+
+#include <memory>
+#include <vector>
+
+namespace com::sun::star::container
+{
+class XIndexAccess;
+}
+namespace com::sun::star::uno
+{
+template <typename> class Reference;
+}
+namespace sd
+{
+class FuPoor;
+}
+namespace sd
+{
+class Window;
+}
+namespace vcl
+{
+class Window;
+}
+
+namespace sd::slidesorter
+{
+class SlideSorter;
+}
+namespace sd::slidesorter::view
+{
+class SlideSorterView;
+}
+namespace sd::slidesorter::model
+{
+class SlideSorterModel;
+}
+
+class CommandEvent;
+class SdPage;
+class SfxItemSet;
+class SfxRequest;
+class VclSimpleEvent;
+class VclWindowEvent;
+
+namespace sd::slidesorter::controller
+{
+class Animator;
+class Clipboard;
+class CurrentSlideManager;
+class FocusManager;
+class InsertionIndicatorHandler;
+class Listener;
+class PageSelector;
+class ScrollBarManager;
+class SelectionFunction;
+class SelectionManager;
+class SlotManager;
+class VisibleAreaManager;
+
+class SlideSorterController final
+{
+public:
+    /** Create a new controller for the slide sorter.
+        @param pParentWindow
+            The window that contains the controls of the new
+            controller.
+    */
+    SlideSorterController(SlideSorter& rSlideSorter);
+
+    /** Late initialization. Call this method once a new object has been
+        created.
+    */
+    void Init();
+
+    ~SlideSorterController();
+
+    void Dispose();
+
+    /** Place and size the scroll bars and the browser window so that the
+        given rectangle is filled.
+    */
+    void Resize(const ::tools::Rectangle& rAvailableSpace);
+
+    /** Determine which of the UI elements--the scroll bars, the scroll bar
+        filler, the actual slide sorter view--are visible and place them in
+        the area last passed to Resize().
+        @param bForce
+            When <TRUE/> is given (<FALSE/> is the default) then the content
+            window and with it the SlideSorterView is resized event when its
+            size does not change (the size does change when the visibility
+            of scroll bars changes.)
+    */
+    void Rearrange(bool bForce);
+
+    /** Return the descriptor of the page that is rendered under the
+        given position.  This takes the IsOnlyPreviewTriggersMouseOver
+        property into account.
+        @return
+            Returns a pointer to a page descriptor instead of a
+            reference because when no page is found at the position
+            then NULL is returned to indicate this.
+    */
+    model::SharedPageDescriptor GetPageAt(const Point& rPixelPosition);
+
+    // Exported for unit test
+    SD_DLLPUBLIC PageSelector& GetPageSelector();
+    FocusManager& GetFocusManager();
+    // Exported for unit test
+    SD_DLLPUBLIC controller::Clipboard& GetClipboard();
+
+    /** Return the object that manages the scroll bars.
+    */
+    ScrollBarManager& GetScrollBarManager();
+
+    std::shared_ptr<CurrentSlideManager> const& GetCurrentSlideManager() const;
+    std::shared_ptr<SlotManager> const& GetSlotManager() const;
+    std::shared_ptr<SelectionManager> const& GetSelectionManager() const;
+    std::shared_ptr<InsertionIndicatorHandler> const& GetInsertionIndicatorHandler() const;
+
+    /** This method forwards the call to the SlideSorterView and executes
+        pending operations like moving selected pages into the visible area.
+    */
+    void Paint(const ::tools::Rectangle& rRect, vcl::Window* pWin);
+
+    void FuTemporary(SfxRequest& rRequest);
+    void FuPermanent(SfxRequest& rRequest);
+    void FuSupport(SfxRequest& rRequest);
+    bool Command(const CommandEvent& rEvent, ::sd::Window* pWindow);
+
+    void GetCtrlState(SfxItemSet& rSet);
+    void GetStatusBarState(SfxItemSet& rSet);
+
+    void ExecCtrl(SfxRequest& rRequest);
+    void GetAttrState(SfxItemSet& rSet);
+
+    /** Create an object of this inner class to prevent updates due to model
+        changes.
+    */
+    class ModelChangeLock
+    {
+    public:
+        ModelChangeLock(SlideSorterController& rController);
+        ~ModelChangeLock() COVERITY_NOEXCEPT_FALSE;
+        void Release();
+
+    private:
+        SlideSorterController* mpController;
+    };
+    friend class ModelChangeLock;
+
+    /** Handle a change of the model, that is, handle the removal and
+        insertion of whole pages or a change of the edit mode.
+
+        This method is a convenience function that simply calls
+        PreModelChange() and then PostModelChange().
+    */
+    void HandleModelChange();
+
+    DECL_LINK(WindowEventHandler, VclWindowEvent&, void);
+    DECL_LINK(ApplicationEventHandler, VclSimpleEvent&, void);
+
+    /** Update the display of all pages.  This involves a redraw and
+        releasing previews and caches.
+    */
+    void UpdateAllPages();
+
+    /** This factory method creates a selection function.
+    */
+    rtl::Reference<FuPoor> CreateSelectionFunction(SfxRequest& rRequest);
+
+    /** When the current function of the view shell is the slide sorter
+        selection function then return a reference to it.  Otherwise return
+        an empty reference.
+    */
+    ::rtl::Reference<SelectionFunction> GetCurrentSelectionFunction() const;
+
+    /** Prepare for a change of the edit mode.  Depending on the current
+        edit mode we may save the selection so that it can be restored when
+        later changing back to the current edit mode.
+    */
+    void PrepareEditModeChange();
+
+    /** Set a new edit mode and return whether the edit mode really
+        has been changed.  For proper saving and restoring of the selection
+        this method should be called between calls to
+        PrepareEditModeChange() and FinishEditModeChange().
+    */
+    void ChangeEditMode(EditMode eEditMode);
+
+    /** Finish the change of the edit mode.  Here we may select a page or
+        restore a previously saved selection.
+    */
+    void FinishEditModeChange();
+
+    /** Call this method when the name of one of the pages has changed.
+        This is then notified to the accessibility object, when that exists.
+        @param nPageIndex
+            The index of the page whose name has been changed.
+        @param rsOldName
+            The old name of the page.  The new name can be taken from the
+            page object.
+    */
+    void PageNameHasChanged(int nPageIndex, const OUString& rsOldName);
+
+    /** Provide the set of pages to be displayed in the slide sorter.  The
+        GetDocumentSlides() method can be found only in the SlideSorterModel.
+    */
+    void SetDocumentSlides(const css::uno::Reference<css::container::XIndexAccess>& rxSlides);
+
+    /** Return an Animator object.
+    */
+    const std::shared_ptr<Animator>& GetAnimator() const { return mpAnimator; }
+
+    VisibleAreaManager& GetVisibleAreaManager() const;
+
+    void CheckForMasterPageAssignment();
+    void CheckForSlideTransitionAssignment();
+
+private:
+    SlideSorter& mrSlideSorter;
+    model::SlideSorterModel& mrModel;
+    view::SlideSorterView& mrView;
+    std::unique_ptr<PageSelector> mpPageSelector;
+    std::unique_ptr<FocusManager> mpFocusManager;
+    std::shared_ptr<SlotManager> mpSlotManager;
+    std::unique_ptr<ScrollBarManager> mpScrollBarManager;
+    mutable std::shared_ptr<CurrentSlideManager> mpCurrentSlideManager;
+    std::shared_ptr<SelectionManager> mpSelectionManager;
+    std::unique_ptr<controller::Clipboard> mpClipboard;
+    std::shared_ptr<InsertionIndicatorHandler> mpInsertionIndicatorHandler;
+    std::shared_ptr<Animator> mpAnimator;
+    std::unique_ptr<VisibleAreaManager> mpVisibleAreaManager;
+
+    // The listener listens to UNO events and thus is a UNO object.
+    ::rtl::Reference<controller::Listener> mpListener;
+
+    int mnModelChangeLockCount;
+    bool mbIsForcedRearrangePending;
+    bool mbContextMenuOpen;
+
+    bool mbPostModelChangePending;
+
+    /** This array stores the indices of the  selected page descriptors at
+        the time when the edit mode is switched to EditMode::MasterPage.  With this
+        we can restore the selection when switching back to EditMode::Page mode.
+    */
+    ::std::vector<SdPage*> maSelectionBeforeSwitch;
+    /// The current page before the edit mode is switched to EditMode::MasterPage.
+    int mnCurrentPageBeforeSwitch;
+
+    /** The master page to select after the edit mode is changed.  This
+        member is used to pass the pointer from PrepareEditModeChange() to
+        FinishEditModeChange().
+    */
+    SdPage* mpEditModeChangeMasterPage;
+
+    /** This rectangle in the parent window encloses scroll bars and slide
+        sorter window.  It is set when Resize() is called.
+    */
+    ::tools::Rectangle maTotalWindowArea;
+
+    /** This counter is used to avoid processing of reentrant calls to
+        Paint().
+    */
+    sal_Int32 mnPaintEntranceCount;
+
+    /** Prepare for several model changes, i.e. prevent time-consuming and
+        non-critical operations like repaints until UnlockModelChange() is
+        called. Critical operations like releasing references to pages that
+        do not exist anymore are executed.
+    */
+    void LockModelChange();
+
+    /** Further calls to HandleModelChange() will result in a full featured
+        update of model, view, and controller.  When HandleModelChange() has
+        been called since the last LockModelChange() then this is done right
+        away to bring the view up-to-date.
+    */
+    void UnlockModelChange();
+
+    /** Prepare for a model change.  This method does all the things that
+        need to be done _before_ the model changes, e.g. because they need
+        access to the model data before the change.
+    */
+    void PreModelChange();
+
+    /** Complete a model change.  This includes the recreation of data
+        structures that depend on the model and the request for a repaint to
+        show the changes.
+    */
+    void PostModelChange();
+};
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/controller/SlsAnimationFunction.hxx b/sd/source/ui/slidesorter/inc/controller/SlsAnimationFunction.hxx
new file mode 100644
index 000000000..b4847de1a
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/controller/SlsAnimationFunction.hxx
@@ -0,0 +1,77 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <basegfx/point/b2dpoint.hxx>
+
+#include <functional>
+#include <vector>
+
+
+namespace sd::slidesorter::controller {
+
+class AnimationBezierFunction
+{
+public:
+    /** Create a cubic bezier curve whose start and end points are given
+        implicitly as P0=(0,0) and P3=(1,1).  The second control point is
+        implicitly given as P2=(1-nY1,1-nX1).
+    */
+    AnimationBezierFunction (
+        const double nX1,
+        const double nY1);
+
+    ::basegfx::B2DPoint operator() (const double nT);
+
+private:
+    const double mnX1;
+    const double mnY1;
+    const double mnX2;
+    const double mnY2;
+
+    static double EvaluateComponent (
+        const double nT,
+        const double nV1,
+        const double nV2);
+};
+
+/** Turn a parametric function into one whose y-Values depend on its
+    x-Values.  Note a lot of interpolation takes place.  The resulting
+    accuracy should be good enough for the purpose of acceleration
+    function for animations.
+*/
+class AnimationParametricFunction
+{
+public:
+    typedef ::std::function<basegfx::B2DPoint (double)> ParametricFunction;
+    AnimationParametricFunction (const ParametricFunction& rFunction);
+
+    double operator() (const double nX);
+
+private:
+    /** y-Values of the parametric function given to the constructor
+        evaluated (and interpolated) for evenly spaced x-Values.
+    */
+    ::std::vector<double> maY;
+};
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/controller/SlsAnimator.hxx b/sd/source/ui/slidesorter/inc/controller/SlsAnimator.hxx
new file mode 100644
index 000000000..8c9ec9e81
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/controller/SlsAnimator.hxx
@@ -0,0 +1,122 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <view/SlideSorterView.hxx>
+#include <canvas/elapsedtime.hxx>
+#include <vcl/idle.hxx>
+#include <sal/types.h>
+#include <o3tl/deleter.hxx>
+
+#include <functional>
+#include <memory>
+#include <vector>
+
+namespace sd::slidesorter { class SlideSorter; }
+
+namespace sd::slidesorter::controller {
+
+/** Experimental class for simple eye candy animations.
+*/
+class Animator
+{
+public:
+    /** In some circumstances we have to avoid animation and jump to the
+        final animation state immediately.  Use this enum instead of a bool
+        to be more expressive.
+    */
+    enum AnimationMode { AM_Animated, AM_Immediate };
+
+    explicit Animator (SlideSorter& rSlideSorter);
+    ~Animator();
+    Animator(const Animator&) = delete;
+    Animator& operator=(const Animator&) = delete;
+
+    /** When disposed the animator will stop its work immediately and not
+        process any timer events anymore.
+    */
+    void Dispose();
+
+    /** An animation object is called with values between 0 and 1 as single
+        argument to its operator() method.
+    */
+    typedef ::std::function<void (double)> AnimationFunctor;
+    typedef ::std::function<void ()> FinishFunctor;
+
+    typedef sal_Int32 AnimationId;
+    static const AnimationId NotAnAnimationId = -1;
+
+    /** Schedule a new animation for execution.  The () operator of that
+        animation will be called with increasing values between 0 and 1 for
+        the specified duration.
+        @param rAnimation
+            The animation operation.
+    */
+    AnimationId AddAnimation (
+        const AnimationFunctor& rAnimation,
+        const FinishFunctor& rFinishFunctor);
+
+    /** Abort and remove an animation.  In order to reduce the bookkeeping
+        on the caller side, it is OK to call this method with an animation
+        function that is not currently being animated.  Such a call is
+        silently ignored.
+    */
+    void RemoveAnimation (const AnimationId nAnimationId);
+
+    /** A typical use case for this method is the temporary shutdown of the
+        slidesorter when the slide sorter bar is put into a cache due to a
+        change of the edit mode.
+    */
+    void RemoveAllAnimations();
+
+private:
+    SlideSorter& mrSlideSorter;
+    Idle maIdle;
+    bool mbIsDisposed;
+    class Animation;
+    typedef ::std::vector<std::shared_ptr<Animation> > AnimationList;
+    AnimationList maAnimations;
+    ::canvas::tools::ElapsedTime maElapsedTime;
+
+    std::unique_ptr<view::SlideSorterView::DrawLock, o3tl::default_delete<view::SlideSorterView::DrawLock>> mpDrawLock;
+
+    AnimationId mnNextAnimationId;
+
+    DECL_LINK(TimeoutHandler, Timer *, void);
+
+    /** Execute one step of every active animation.
+        @param nTime
+            Time measured in milliseconds with some arbitrary reference point.
+        @return
+            When one or more animation has finished then <TRUE/> is
+            returned.  Call CleanUpAnimationList() in this case.
+    */
+    bool ProcessAnimations (const double nTime);
+
+    /** Remove animations that have expired.
+    */
+    void CleanUpAnimationList();
+
+    void RequestNextFrame();
+};
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/controller/SlsClipboard.hxx b/sd/source/ui/slidesorter/inc/controller/SlsClipboard.hxx
new file mode 100644
index 000000000..6ced17486
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/controller/SlsClipboard.hxx
@@ -0,0 +1,208 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <memory>
+#include <ViewClipboard.hxx>
+#include <controller/SlsSelectionObserver.hxx>
+#include <sdxfer.hxx>
+
+#include <sal/types.h>
+#include <o3tl/deleter.hxx>
+#include <svx/svdtypes.hxx>
+
+#include <sddllapi.h>
+
+class SfxRequest;
+struct AcceptDropEvent;
+class DropTargetHelper;
+struct ExecuteDropEvent;
+struct ImplSVEvent;
+class Point;
+class SdPage;
+namespace vcl { class Window; }
+
+namespace sd {
+class Window;
+}
+
+namespace sd::slidesorter { class SlideSorter; }
+
+namespace sd::slidesorter::controller {
+
+class SlideSorterController;
+
+class SAL_DLLPUBLIC_RTTI Clipboard final
+    : public ViewClipboard
+{
+public:
+    Clipboard (SlideSorter& rSlideSorter);
+    virtual ~Clipboard() override;
+
+    /** Create a slide sorter transferable from the given sd
+        transferable.  The returned transferable is set up with all
+        information necessary so that it can be dropped on a slide sorter.
+    */
+    static std::shared_ptr<SdTransferable::UserData> CreateTransferableUserData (SdTransferable* pTransferable);
+
+    void HandleSlotCall (SfxRequest& rRequest);
+
+    void DoCut ();
+    // Exported for unit test
+    SD_DLLPUBLIC void DoCopy();
+    // Exported for unit test
+    SD_DLLPUBLIC void DoPaste();
+    void DoDelete ();
+
+    void StartDrag (
+        const Point& rDragPt,
+        vcl::Window* pWindow );
+
+    void DragFinished (
+        sal_Int8 nDropAction);
+
+    sal_Int8 AcceptDrop (
+        const AcceptDropEvent& rEvt,
+        DropTargetHelper& rTargetHelper,
+        ::sd::Window* pTargetWindow,
+        sal_uInt16 nPage,
+        SdrLayerID nLayer );
+
+    sal_Int8 ExecuteDrop (
+        const ExecuteDropEvent& rEvt,
+        DropTargetHelper& rTargetHelper,
+        ::sd::Window* pTargetWindow,
+        sal_uInt16 nPage,
+        SdrLayerID nLayer );
+
+    void Abort();
+
+private:
+    virtual sal_uInt16 DetermineInsertPosition () override;
+
+    SlideSorter& mrSlideSorter;
+    SlideSorterController& mrController;
+
+    typedef ::std::vector<SdPage*> PageList;
+    /** Remember the pages that are dragged to another document or to
+        another place in the same document so that they can be removed after
+        a move operation.
+    */
+    PageList maPagesToRemove;
+
+    /** Used when a drop is executed to combine all undo actions into one.
+        Typically created in ExecuteDrop() and released in DragFinish().
+    */
+    class UndoContext;
+    std::unique_ptr<UndoContext> mxUndoContext;
+
+    std::unique_ptr<SelectionObserver::Context, o3tl::default_delete<SelectionObserver::Context>> mxSelectionObserverContext;
+    ImplSVEvent * mnDragFinishedUserEventId;
+
+    void CreateSlideTransferable (
+        vcl::Window* pWindow,
+        bool bDrag);
+
+    /** Determine the position of where to insert the pages in the current
+        transferable of the sd module.
+        @return
+            The index in the range [0,n] (both inclusive) with n the number
+            of pages is returned.
+    */
+    sal_Int32 GetInsertionPosition ();
+
+    /** Paste the pages of the transferable of the sd module at the given
+        position.
+        @param nInsertPosition
+            The position at which to insert the pages.  The valid range is
+            [0,n] (both inclusive) with n the number of pages in the
+            document.
+        @return
+            The number of inserted pages is returned.
+    */
+    sal_Int32 PasteTransferable (sal_Int32 nInsertPosition);
+
+    /** Select a range of pages of the model.  Typically usage is the
+        selection of newly inserted pages.
+        @param nFirstIndex
+            The index of the first page to select.
+        @param nPageCount
+            The number of pages to select.
+    */
+    void SelectPageRange (sal_Int32 nFirstIndex, sal_Int32 nPageCount);
+
+    /** Return <TRUE/> when the current transferable in the current state of
+        the slidesorter is acceptable to be pasted.  For this the
+        transferable has to
+        a) exist,
+        b) contain one or more regular draw pages, no master pages.
+        When master pages are involved, either in the transferable or in the
+        slide sorter (by it displaying master pages) the drop of the
+        transferable is not accepted.  The reason is the missing
+        implementation of proper handling master pages copy-and-paste.
+    */
+    enum DropType { DT_PAGE, DT_PAGE_FROM_NAVIGATOR, DT_SHAPE, DT_NONE };
+    DropType IsDropAccepted() const;
+
+    /** This method contains the code for AcceptDrop() and ExecuteDrop() shapes.
+        There are only minor differences for the two cases at this level.
+        @param eCommand
+            This parameter specifies whether to do an AcceptDrop() or
+            ExecuteDrop().
+        @param rPosition
+            Since the event is given as void pointer we can not take the
+            mouse position from it.  The caller has to supply it in this
+            parameter.
+        @param pDropEvent
+            Event though the AcceptDropEvent and ExecuteDropEvent are very
+            similar they do not have a common base class.  Because of that
+            we have to use a void* to pass these structs.
+        @param nPage
+            When the page number is given as 0xffff then it is replaced by
+            the number of the page at the mouse position.  If the mouse is
+            not over a page then neither AcceptDrop() nor ExecuteDrop() are
+            executed.
+    */
+    enum DropCommand { DC_ACCEPT, DC_EXECUTE };
+    sal_Int8 ExecuteOrAcceptShapeDrop (
+        DropCommand eCommand,
+        const Point& rPosition,
+        const void* pDropEvent ,
+        DropTargetHelper& rTargetHelper,
+        ::sd::Window* pTargetWindow,
+        sal_uInt16 nPage,
+        SdrLayerID nLayer);
+
+    /** Return whether the insertion defined by the transferable is
+        trivial, ie would not change either source nor target document.
+    */
+    bool IsInsertionTrivial (
+        SdTransferable const * pTransferable,
+        const sal_Int8 nDndAction) const;
+
+    /** Asynchronous part of DragFinished.  The argument is the sal_Int8
+        nDropAction, disguised as void*.
+    */
+    DECL_DLLPRIVATE_LINK(ProcessDragFinished, void*, void);
+};
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/controller/SlsCurrentSlideManager.hxx b/sd/source/ui/slidesorter/inc/controller/SlsCurrentSlideManager.hxx
new file mode 100644
index 000000000..0c5b3b243
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/controller/SlsCurrentSlideManager.hxx
@@ -0,0 +1,112 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <model/SlsSharedPageDescriptor.hxx>
+#include <vcl/timer.hxx>
+#include <tools/link.hxx>
+
+class SdPage;
+
+namespace sd::slidesorter
+{
+class SlideSorter;
+}
+
+namespace sd::slidesorter::controller
+{
+/** Manage the current slide.  This includes setting the according flags at
+    the PageDescriptor objects and setting the current slide at the main
+    view shell.
+
+    Switching pages is triggered only after a little delay.  This allows
+    fast travelling through a larger set of slides without having to wait
+    for the edit view to update its content after every slide change.
+*/
+class CurrentSlideManager
+{
+public:
+    /** Create a new CurrentSlideManager object that manages the current
+        slide for the given SlideSorter.
+    */
+    CurrentSlideManager(SlideSorter& rSlideSorter);
+
+    ~CurrentSlideManager();
+
+    /** Call this when the current page of the main view shell has been
+        switched.  Use SwitchCurrentSlide() to initiate such a switch.
+    */
+    void NotifyCurrentSlideChange(const sal_Int32 nSlideIndex);
+    void NotifyCurrentSlideChange(const SdPage* pPage);
+
+    /** Call this method to switch the current page of the main view shell
+        to the given slide.  Use CurrentSlideHasChanged() when the current
+        slide change has been initiated by someone else.
+        @param nSlideIndex
+            Zero based index in the range [0,number-of-slides).
+         The page selection is cleared and only the new
+            current slide is selected.
+    */
+    void SwitchCurrentSlide(const sal_Int32 nSlideIndex);
+    void SwitchCurrentSlide(const model::SharedPageDescriptor& rpSlide,
+                            const bool bUpdateSelection = false);
+
+    /** Return the page descriptor for the current slide.  Note, that when
+        there is no current slide then the returned pointer is empty.
+    */
+    const model::SharedPageDescriptor& GetCurrentSlide() const { return mpCurrentSlide; }
+
+    /** Release all references to model data.
+    */
+    void PrepareModelChange();
+
+    /** Modify inner state in reaction to a change of the SlideSorterModel.
+    */
+    void HandleModelChange();
+
+private:
+    SlideSorter& mrSlideSorter;
+    sal_Int32 mnCurrentSlideIndex;
+    model::SharedPageDescriptor mpCurrentSlide;
+    /** Timer to control the delay after which to ask
+        XController/ViewShellBase to switch to another slide.
+    */
+    Timer maSwitchPageDelayTimer;
+
+    void SetCurrentSlideAtViewShellBase(const model::SharedPageDescriptor& rpSlide);
+    void SetCurrentSlideAtTabControl(const model::SharedPageDescriptor& rpSlide);
+    void SetCurrentSlideAtXController(const model::SharedPageDescriptor& rpSlide);
+
+    /** When switching from one slide to a new current slide then this
+        method releases all ties to the old slide.
+    */
+    void ReleaseCurrentSlide();
+
+    /** When switching from one slide to a new current slide then this
+        method connects to the new current slide.
+    */
+    void AcquireCurrentSlide(const sal_Int32 nSlideIndex);
+
+    DECL_LINK(SwitchPageCallback, Timer*, void);
+};
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/controller/SlsFocusManager.hxx b/sd/source/ui/slidesorter/inc/controller/SlsFocusManager.hxx
new file mode 100644
index 000000000..180b7143f
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/controller/SlsFocusManager.hxx
@@ -0,0 +1,211 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <model/SlsSharedPageDescriptor.hxx>
+
+#include <sal/types.h>
+#include <tools/link.hxx>
+#include <vector>
+
+namespace sd::slidesorter
+{
+class SlideSorter;
+}
+
+namespace sd::slidesorter::controller
+{
+/** This class manages the focus of the slide sorter.  There is the focus
+    page which is or is not focused.  Initialized to point to the first page
+    it can be set to other pages by using the MoveFocus() method.  The
+    focused state of the focus page can be toggled with the ToggleFocus()
+    method.
+*/
+class FocusManager
+{
+public:
+    /** Create a new focus manager that operates on the pages of the model
+        associated with the given controller.  The focus page is set to the
+        first page.  Focused state is off.
+    */
+    FocusManager(SlideSorter& rSlideSorter);
+
+    ~FocusManager();
+
+    enum class FocusMoveDirection
+    {
+        Left,
+        Right,
+        Up,
+        Down
+    };
+
+    /** Move the focus from the currently focused page to one that is
+        displayed adjacent to it, either vertically or horizontally.
+        @param eDirection
+            Direction in which to move the focus.  Wrap around is done
+            differently when moving vertically or horizontally.  Vertical
+            wrap around takes place in the same column, i.e. when you are
+            in the top row and move up you come out in the bottom row in the
+            same column.  Horizontal wrap around moves to the next
+            (FocusMoveDirection::Right) or previous (FocusMoveDirection::Left) page.  Moving to the right
+            from the last page goes to the first page and vice versa.
+            The current page index is set to the nearest valid
+            page index.
+    */
+    void MoveFocus(FocusMoveDirection eDirection);
+
+    /** Show the focus indicator of the current slide.
+        @param bScrollToFocus
+            When <TRUE/> (the default) then the view is scrolled so that the
+            focus rectangle lies inside its visible area.
+    */
+    void ShowFocus(const bool bScrollToFocus = true);
+
+    /** Hide the focus indicator.
+    */
+    void HideFocus();
+
+    /** Toggle the focused state of the current slide.
+        @return
+            Returns the focused state of the focus page after the call.
+    */
+    bool ToggleFocus();
+
+    /** Return whether the window managed by the called focus manager has
+        the input focus of the application.
+    */
+    bool HasFocus() const;
+
+    /** Return the descriptor of the page that currently has the focus.
+        @return
+            When there is no page that currently has the focus then NULL is
+            returned.
+    */
+    model::SharedPageDescriptor GetFocusedPageDescriptor() const;
+
+    /** Return the index of the page that currently has the focus as it is
+        accepted by the slide sorter model.
+        @return
+            When there is no page that currently has the focus then -1 is
+            returned.
+    */
+    sal_Int32 GetFocusedPageIndex() const { return mnPageIndex; }
+
+    /** Set the focused page to the one described by the given page
+        descriptor.  The visibility of the focus indicator is not modified.
+        @param rDescriptor
+            One of the page descriptors that are currently managed by the
+            SlideSorterModel.
+    */
+    bool SetFocusedPage(const model::SharedPageDescriptor& rDescriptor);
+
+    /** Set the focused page to the one described by the given page
+        index.  The visibility of the focus indicator is not modified.
+        @param nPageIndex
+            A valid page index that is understood by the SlideSorterModel.
+    */
+    void SetFocusedPage(sal_Int32 nPageIndex);
+
+    bool SetFocusedPageToCurrentPage();
+
+    /** Return <TRUE/> when the focus indicator is currently shown.  A
+        prerequisite is that the window managed by this focus manager has
+        the input focus as indicated by a <TRUE/> return value of
+        HasFocus().  It is not necessary that the focus indicator is
+        visible.  It may have been scrolled outside the visible area.
+    */
+    bool IsFocusShowing() const;
+
+    /** Add a listener that is called when the focus is shown or hidden or
+        set to another page object.
+        @param rListener
+            When this method is called multiple times for the same listener
+            the second and all following calls are ignored.  Each listener
+            is added only once.
+    */
+    void AddFocusChangeListener(const Link<LinkParamNone*, void>& rListener);
+
+    /** Remove a focus change listener.
+        @param rListener
+            It is safe to pass a listener that was not added are has been
+            removed previously.  Such calls are ignored.
+    */
+    void RemoveFocusChangeListener(const Link<LinkParamNone*, void>& rListener);
+
+    /** Create an instance of this class to temporarily hide the focus
+        indicator.  It is restored to its former visibility state when the
+        FocusHider is destroyed.
+    */
+    class FocusHider
+    {
+    public:
+        FocusHider(FocusManager&);
+        ~FocusHider() COVERITY_NOEXCEPT_FALSE;
+
+    private:
+        bool mbFocusVisible;
+        FocusManager& mrManager;
+    };
+
+private:
+    SlideSorter& mrSlideSorter;
+
+    /** Index of the page that may be focused.  It is -1 when the model
+        contains no page.
+    */
+    sal_Int32 mnPageIndex;
+
+    /** This flag indicates whether the page pointed to by mpFocusDescriptor
+        has the focus.
+    */
+    bool mbPageIsFocused;
+
+    ::std::vector<Link<LinkParamNone*, void>> maFocusChangeListeners;
+
+    /** Reset the focus state of the given descriptor and request a repaint
+        so that the focus indicator is hidden.
+        @param pDescriptor
+            When NULL is given then the call is ignored.
+    */
+    void HideFocusIndicator(const model::SharedPageDescriptor& rpDescriptor);
+
+    /** Set the focus state of the given descriptor, scroll it into the
+        visible area and request a repaint so that the focus indicator is
+        made visible.
+        @param pDescriptor
+            When NULL is given then the call is ignored.
+        @param bScrollToFocus
+            When <TRUE/> (the default) then the view is scrolled so that the
+            focus rectangle lies inside its visible area.
+    */
+    void ShowFocusIndicator(const model::SharedPageDescriptor& rpDescriptor,
+                            const bool bScrollToFocus);
+
+    /** Call all currently registered listeners that a focus change has
+        happened.  The focus may be hidden or shown or moved from one page
+        object to another.
+    */
+    void NotifyFocusChangeListeners() const;
+};
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/controller/SlsInsertionIndicatorHandler.hxx b/sd/source/ui/slidesorter/inc/controller/SlsInsertionIndicatorHandler.hxx
new file mode 100644
index 000000000..43f2d2f6a
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/controller/SlsInsertionIndicatorHandler.hxx
@@ -0,0 +1,138 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <controller/SlsAnimator.hxx>
+
+#include <view/SlsLayouter.hxx>
+
+namespace sd::slidesorter { class SlideSorter; }
+namespace sd::slidesorter::view {
+class InsertAnimator;
+class InsertionIndicatorOverlay;
+}
+
+class SdTransferable;
+
+namespace sd::slidesorter::controller {
+
+/** Manage the visibility and location of the insertion indicator.  Its
+    actual display is controlled by the InsertionIndicatorOverlay.
+*/
+class InsertionIndicatorHandler
+{
+public:
+    InsertionIndicatorHandler (SlideSorter& rSlideSorter);
+    ~InsertionIndicatorHandler() COVERITY_NOEXCEPT_FALSE;
+
+    enum Mode { CopyMode, MoveMode, UnknownMode };
+    static Mode GetModeFromDndAction (const sal_Int8 nDndAction);
+
+    /** Activate the insertion marker at the given coordinates.
+    */
+    void Start (const bool bIsOverSourceView);
+
+    /** Deactivate the insertion marker.
+    */
+    void End (const controller::Animator::AnimationMode eMode);
+
+    /** This context make sure that the insertion indicator is shown
+        (provided that the clipboard is not empty) while the context is
+        alive.  Typically used while a context menu is displayed.
+    */
+    class ForceShowContext
+    {
+    public:
+        ForceShowContext (const std::shared_ptr<InsertionIndicatorHandler>& rpHandler);
+        ~ForceShowContext() COVERITY_NOEXCEPT_FALSE;
+    private:
+        const std::shared_ptr<InsertionIndicatorHandler> mpHandler;
+    };
+
+    /** Update the indicator icon from the current transferable (from the
+        clipboard or an active drag and drop operation.)
+    */
+    void UpdateIndicatorIcon (const SdTransferable* pTransferable);
+
+    /** Set the position of the insertion marker to the given coordinates.
+    */
+    void UpdatePosition (
+        const Point& rMouseModelPosition,
+        const Mode eMode);
+    void UpdatePosition (
+        const Point& rMouseModelPosition,
+        const sal_Int8 nDndAction);
+
+    /** Return whether the insertion marker is active.
+    */
+    bool IsActive() const { return mbIsActive;}
+
+    /** Return the insertion index that corresponds with the current
+        graphical location of the insertion indicator.
+    */
+    sal_Int32 GetInsertionPageIndex() const;
+
+    /** Determine whether moving the current selection to the current
+        position of the insertion marker would alter the document.  This
+        would be the case when the selection is not consecutive or would be
+        moved to a position outside and not adjacent to the selection.
+    */
+    bool IsInsertionTrivial (
+        const sal_Int32 nInsertionIndex,
+        const Mode eMode) const;
+    /** This method is like the other variant.  It operates implicitly
+        on the current insertion index as would be returned by
+        GetInsertionPageIndex().
+    */
+    bool IsInsertionTrivial (const sal_Int8 nDndAction);
+
+private:
+    SlideSorter& mrSlideSorter;
+    std::shared_ptr<view::InsertAnimator> mpInsertAnimator;
+    std::shared_ptr<view::InsertionIndicatorOverlay> mpInsertionIndicatorOverlay;
+    view::InsertPosition maInsertPosition;
+    Mode meMode;
+    bool mbIsInsertionTrivial;
+    bool mbIsActive;
+    bool mbIsReadOnly;
+    bool mbIsOverSourceView;
+    Size maIconSize;
+    bool mbIsForcedShow;
+
+    void SetPosition (
+        const Point& rPoint,
+        const Mode eMode);
+    std::shared_ptr<view::InsertAnimator> const & GetInsertAnimator();
+
+    /** Make the insertion indicator visible (that is the show part) and
+        keep it visible, even when the mouse leaves the window (that is the
+        force part).  We need this when a context menu is displayed (mouse
+        over the popup menu triggers a mouse leave event) while the
+        insertion indicator remains visible in the background.
+
+        In effect all calls to End() are ignored until ForceEnd() is called.
+    */
+    void ForceShow();
+    void ForceEnd();
+};
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/controller/SlsPageSelector.hxx b/sd/source/ui/slidesorter/inc/controller/SlsPageSelector.hxx
new file mode 100644
index 000000000..6a4b75004
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/controller/SlsPageSelector.hxx
@@ -0,0 +1,219 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <model/SlsSharedPageDescriptor.hxx>
+
+#include <vector>
+#include <memory>
+
+#include <sddllapi.h>
+
+class SdPage;
+
+namespace sd::slidesorter
+{
+class SlideSorter;
+}
+namespace sd::slidesorter::model
+{
+class SlideSorterModel;
+}
+
+namespace sd::slidesorter::controller
+{
+class SlideSorterController;
+
+/** A sub-controller that handles page selection of the slide browser.
+    Selecting a page does not make it the current page (of the main view)
+    automatically as this would not be desired in a multi selection.  This
+    has to be done explicitly by calling the
+    CurrentSlideManager::SetCurrentSlide() method.
+
+    Indices of pages relate always to the number of all pages in the model
+    (as returned by GetPageCount()) not just the selected pages.
+*/
+class PageSelector
+{
+public:
+    explicit PageSelector(SlideSorter& rSlideSorter);
+    PageSelector(const PageSelector&) = delete;
+    PageSelector& operator=(const PageSelector&) = delete;
+
+    // Exported for unit test
+    SD_DLLPUBLIC void SelectAllPages();
+    SD_DLLPUBLIC void DeselectAllPages();
+
+    /** Update the selection state of all page descriptors to be the same as
+        that of the corresponding pages of the SdPage objects and issue
+        redraw requests where necessary.
+    */
+    void GetCoreSelection();
+
+    /** Update the selection state of the SdPage objects to be the same as
+        that of the corresponding page descriptors.
+    */
+    void SetCoreSelection();
+
+    /** Select the specified descriptor.  The selection state of the other
+        descriptors is not affected.
+    */
+    void SelectPage(int nPageIndex);
+    /** Select the descriptor that is associated with the given page.  The
+        selection state of the other descriptors is not affected.
+    */
+    void SelectPage(const SdPage* pPage);
+    /** Select the specified descriptor.  The selection state of the other
+        descriptors is not affected.
+    */
+    void SelectPage(const model::SharedPageDescriptor& rpDescriptor);
+
+    /** Return whether the specified page is selected.  This convenience
+        method is a substitute for
+        SlideSorterModel::GetPageDescriptor(i)->HasState(ST_Selected) is
+        included here to make this class more self contained.
+    */
+    SD_DLLPUBLIC bool IsPageSelected(int nPageIndex);
+
+    /** Return whether the specified page is visible.  This convenience
+        method is a substitute for
+        SlideSorterModel::GetPageDescriptor(i)->HasState(ST_Visible) is
+        included here to make this class more self contained.
+    */
+    bool IsPageVisible(int nPageIndex);
+
+    /** Deselect the descriptor that is associated with the given page.
+        The current page is updated to the first slide
+        of the remaining selection.
+    */
+    void DeselectPage(int nPageIndex);
+    void DeselectPage(const model::SharedPageDescriptor& rpDescriptor,
+                      const bool bUpdateCurrentPage = true);
+
+    /** This convenience method returns the same number of pages that
+        SlideSorterModel.GetPageCount() returns.  It is included here so
+        that it is self contained for iterating over all pages to select or
+        deselect them.
+    */
+    int GetPageCount() const;
+    int GetSelectedPageCount() const { return mnSelectedPageCount; }
+
+    /** Return the anchor for a range selection.  This usually is the first
+        selected page after all pages have been deselected.
+        @return
+            The returned anchor may be NULL.
+    */
+    const model::SharedPageDescriptor& GetSelectionAnchor() const { return mpSelectionAnchor; }
+
+    typedef ::std::vector<SdPage*> PageSelection;
+
+    /** Return an object that describes the current selection.  The caller
+        can use that object to later restore the selection.
+        @return
+            The object returned describes the selection via indices.  So
+            even if pages are exchanged a later call to SetPageSelection()
+            is valid.
+    */
+    std::shared_ptr<PageSelection> GetPageSelection() const;
+
+    /** Restore a page selection according to the given selection object.
+        @param rSelection
+            Typically obtained by calling GetPageSelection() this object
+            is used to restore the selection.  If pages were exchanged since
+            the last call to GetPageSelection() it is still valid to call
+            this method with the selection.  When pages have been inserted
+            or removed the result may be unexpected.
+        @param bUpdateCurrentPage
+            When <TRUE/> (the default value) then after setting the
+            selection update the current page to the first page of the
+            selection.
+            When called from within UpdateCurrentPage() then this flag is
+            used to prevent a recursion loop.
+    */
+    void SetPageSelection(const std::shared_ptr<PageSelection>& rSelection,
+                          const bool bUpdateCurrentPage);
+
+    /** Call this method after the model has changed to set the number
+        of selected pages.
+    */
+    void CountSelectedPages();
+
+    /** Use the UpdateLock whenever you do a complex selection, i.e. call
+        more than one method in a row.  An active lock prevents intermediate
+        changes of the current slide.
+    */
+    class UpdateLock
+    {
+    public:
+        UpdateLock(SlideSorter const& rSlideSorter);
+        UpdateLock(PageSelector& rPageSelector);
+        ~UpdateLock();
+        void Release();
+
+    private:
+        PageSelector* mpSelector;
+    };
+
+    class BroadcastLock
+    {
+    public:
+        BroadcastLock(SlideSorter const& rSlideSorter);
+        BroadcastLock(PageSelector& rPageSelector);
+        ~BroadcastLock();
+
+    private:
+        PageSelector& mrSelector;
+    };
+
+private:
+    model::SlideSorterModel& mrModel;
+    SlideSorter& mrSlideSorter;
+    SlideSorterController& mrController;
+    int mnSelectedPageCount;
+    int mnBroadcastDisableLevel;
+    bool mbSelectionChangeBroadcastPending;
+    model::SharedPageDescriptor mpMostRecentlySelectedPage;
+    /// Anchor for a range selection.
+    model::SharedPageDescriptor mpSelectionAnchor;
+    sal_Int32 mnUpdateLockCount;
+    bool mbIsUpdateCurrentPagePending;
+
+    /** Enable the broadcasting of selection change events.  This calls the
+        SlideSorterController::SelectionHasChanged() method to do the actual
+        work.  When EnableBroadcasting has been called as many times as
+        DisableBroadcasting() was called before and the selection has been
+        changed in the meantime, this change will be broadcasted.
+    */
+    void EnableBroadcasting();
+
+    /** Disable the broadcasting of selection change events.  Subsequent
+        changes of the selection will set a flag that triggers the sending
+        of events when EnableBroadcasting() is called.
+    */
+    void DisableBroadcasting();
+
+    void UpdateCurrentPage(const bool bUpdateOnlyWhenPending = false);
+
+    void CheckConsistency() const;
+};
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/controller/SlsProperties.hxx b/sd/source/ui/slidesorter/inc/controller/SlsProperties.hxx
new file mode 100644
index 000000000..344ac67f3
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/controller/SlsProperties.hxx
@@ -0,0 +1,125 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <tools/color.hxx>
+
+namespace sd::slidesorter::controller
+{
+/** An extensible set of properties used throughout the slide sorter.
+*/
+class Properties
+{
+public:
+    Properties();
+
+    /** Call this method after receiving a VclEventId::ApplicationDataChanged
+        event.
+    */
+    void HandleDataChangeEvent();
+
+    /** When this method returns <TRUE/> then the current slide is
+        highlighted in the view.  The default value is <FALSE/>.
+    */
+    bool IsHighlightCurrentSlide() const { return mbIsHighlightCurrentSlide; }
+    void SetHighlightCurrentSlide(const bool bIsHighlightCurrentSlide);
+
+    /** When this method returns <TRUE/> then the selection is indicated in
+        the view (typically by drawing rectangles around the selected
+        slides.)  The default value is <TRUE/>.
+    */
+    bool IsShowSelection() const { return mbIsShowSelection; }
+    void SetShowSelection(const bool bIsShowSelection);
+
+    /** When this method returns <TRUE/> then the focusdselection is indicated in
+        the view (typically by drawing dotted rectangles around the selected
+        slides.)  The default value is <TRUE/>.
+    */
+    bool IsShowFocus() const { return mbIsShowFocus; }
+    void SetShowFocus(const bool bIsShowFocus);
+
+    /** When this method returns <TRUE/> then on a selection change the
+        visible area is adapted so that the selected slides are shown
+        centered in the view.  This can be used to center the current slide
+        by selecting only the current slide.  The default value is <FALSE/>.
+    */
+    bool IsCenterSelection() const { return mbIsCenterSelection; }
+    void SetCenterSelection(const bool bIsCenterSelection);
+
+    /** When this method returns <TRUE/> then the view may try to change the
+        visible area by scrolling it smoothly on the screen.  Experimental.
+        Default value is <FALSE/>.
+    */
+    bool IsSmoothSelectionScrolling() const { return mbIsSmoothSelectionScrolling; }
+    void SetSmoothSelectionScrolling(const bool bIsSmoothSelectionScrolling);
+
+    /** When this method returns <TRUE/> then during a full screen
+        presentation the previews in a slide sorter are not updated.
+        Default value is <TRUE/>.
+    */
+    bool IsSuspendPreviewUpdatesDuringFullScreenPresentation() const
+    {
+        return mbIsSuspendPreviewUpdatesDuringFullScreenPresentation;
+    }
+    void SetSuspendPreviewUpdatesDuringFullScreenPresentation(const bool bFlag);
+
+    /** Return the background color.
+    */
+    const Color& GetBackgroundColor() const { return maBackgroundColor; }
+    void SetBackgroundColor(const Color& rColor);
+
+    /** Return the text color.
+    */
+    const Color& GetTextColor() const { return maTextColor; }
+    void SetTextColor(const Color& rColor);
+
+    /** Return the color in which selections are to be painted.
+    */
+    const Color& GetSelectionColor() const { return maSelectionColor; }
+    void SetSelectionColor(const Color& rColor);
+
+    /** Return the color used for highlighting e.g. the current slide.
+    */
+    const Color& GetHighlightColor() const { return maHighlightColor; }
+    void SetHighlightColor(const Color& rColor);
+
+    /** The UI can be set to be read only independently from the model status.
+        Used for instance in the presenter view.
+    */
+    bool IsUIReadOnly() const { return mbIsUIReadOnly; }
+    void SetUIReadOnly(const bool bIsUIReadOnly);
+
+private:
+    bool mbIsHighlightCurrentSlide;
+    bool mbIsShowSelection;
+    bool mbIsShowFocus;
+    bool mbIsCenterSelection;
+    bool mbIsSmoothSelectionScrolling;
+    bool mbIsSuspendPreviewUpdatesDuringFullScreenPresentation;
+    Color maBackgroundColor;
+    Color maTextColor;
+    Color maSelectionColor;
+    Color maHighlightColor;
+    bool mbIsUIReadOnly;
+};
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/controller/SlsScrollBarManager.hxx b/sd/source/ui/slidesorter/inc/controller/SlsScrollBarManager.hxx
new file mode 100644
index 000000000..853d98f4a
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/controller/SlsScrollBarManager.hxx
@@ -0,0 +1,248 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <tools/link.hxx>
+#include <tools/gen.hxx>
+#include <vcl/timer.hxx>
+#include <vcl/scrbar.hxx>
+#include <vcl/vclptr.hxx>
+
+#include <functional>
+
+namespace sd { class Window; }
+
+namespace sd::slidesorter { class SlideSorter; }
+
+namespace sd::slidesorter::controller {
+
+/** Manage the horizontal and vertical scroll bars.  Listen for events, set
+    their sizes, place them in the window, determine their visibilities.
+
+    <p>Handle auto scrolling, i.e. the scrolling of the window when the
+    mouse comes near the window border while dragging a selection.</p>
+
+    <p>In order to make the slide sorter be used in the task pane with its
+    own vertical scrollbars the vertical scrollbar of the use of the slide
+    sorter is optional.  When using it the available area in a window is
+    used and the vertical scrollbar is displayed when that area is not large
+    enough.  When the vertical scrollbar is not used then the available area
+    is assumed to be modifiable.  In that case the PlaceScrollBars() method
+    may return an area larger than the one given.<p>
+*/
+class ScrollBarManager
+{
+public:
+    /** Create a new scroll bar manager that manages three controls: the
+        horizontal scroll bar, the vertical scroll bar, and the little
+        window that fills the gap at the bottom right corner that is left
+        between the two scroll bars.  Call LateInitialization() after
+        constructing a new object.
+    */
+    ScrollBarManager (SlideSorter& rSlideSorter);
+
+    ~ScrollBarManager();
+
+    /** Register listeners at the scroll bars.  This method is called after
+        startup of a new slide sorter object or after a reactivation of a
+        slide sorter that for example is taken from a cache.
+    */
+    void Connect();
+
+    /** Remove listeners from the scroll bars.  This method is called when
+        the slide sorter is destroyed or when it is suspended, e.g. put
+        into a cache for later reuse.
+    */
+    void Disconnect();
+
+    /** Set up the scroll bar, i.e. thumb size and position.  Call this
+        method when the content of the browser window changed, i.e. pages
+        were inserted or deleted, the layout or the zoom factor has
+        changed.
+        @param bScrollToCurrentPosition
+            When <TRUE/> then scroll the window to the new offset that is
+            defined by the scroll bars.  Otherwise the new offset is simply
+            set and the whole window is repainted.
+    */
+    void UpdateScrollBars (
+        bool bScrollToCurrentPosition);
+
+    /** Place the scroll bars inside the given area.  When the available
+        area is not large enough for the content to display the horizontal
+        and/or vertical scroll bar is enabled.
+        @param rAvailableArea
+            The scroll bars will be placed inside this rectangle.  It is
+            expected to be given in pixel relative to its parent.
+        @param bIsHorizontalScrollBarAllowed
+            Only when this flag is <TRUE/> the horizontal scroll may be
+            displayed.
+        @param bIsVerticalScrollBarAllowed
+            Only when this flag is <TRUE/> the horizontal scroll may be
+            displayed.
+        @return
+            Returns the space that remains after the scroll bars are
+            placed.
+    */
+    ::tools::Rectangle PlaceScrollBars (
+        const ::tools::Rectangle& rAvailableArea,
+        const bool bIsHorizontalScrollBarAllowed,
+        const bool bIsVerticalScrollBarAllowed);
+
+    /** Update the vertical and horizontal scroll bars so that the visible
+        area has the given top and left values.
+    */
+    void SetTopLeft (const Point& rNewTopLeft);
+
+    /** Return the width of the vertical scroll bar, which--when
+        shown--should be fixed in contrast to its height.
+        @return
+           Returns 0 when the vertical scroll bar is not shown or does not
+           exist, otherwise its width in pixel is returned.
+    */
+    int GetVerticalScrollBarWidth() const;
+
+    /** Return the height of the horizontal scroll bar, which--when
+        shown--should be fixed in contrast to its width.
+        @return
+           Returns 0 when the vertical scroll bar is not shown or does not
+           exist, otherwise its height in pixel is returned.
+    */
+    int GetHorizontalScrollBarHeight() const;
+
+    /** Call this method to scroll a window while the mouse is in dragging a
+        selection.  If the mouse is near the window border or is outside the
+        window then scroll the window accordingly.
+        @param rMouseWindowPosition
+            The mouse position for which the scroll amount is calculated.
+        @param rAutoScrollFunctor
+            Every time when the window is scrolled then this functor is executed.
+        @return
+            When the window is scrolled then this method returns <TRUE/>.
+            When the window is not changed then <FALSE/> is returned.
+    */
+    bool AutoScroll (
+        const Point& rMouseWindowPosition,
+        const ::std::function<void ()>& rAutoScrollFunctor);
+
+    void StopAutoScroll();
+
+    void clearAutoScrollFunctor();
+
+    enum Orientation { Orientation_Horizontal, Orientation_Vertical };
+    /** Scroll the slide sorter by setting the thumbs of the scroll bars and
+        by moving the content of the content window.
+        @param eOrientation
+            Defines whether to scroll horizontally or vertically.
+        @param nDistance
+            distance in slides.
+    */
+    void Scroll(
+        const Orientation eOrientation,
+        const sal_Int32 nDistance);
+
+private:
+    SlideSorter& mrSlideSorter;
+
+    /** The horizontal scroll bar.  Note that is used but not owned by
+        objects of this class.  It is given to the constructor.
+    */
+    VclPtr<ScrollBar> mpHorizontalScrollBar;
+
+    /** The vertical scroll bar.  Note that is used but not owned by
+        objects of this class.  It is given to the constructor.
+    */
+    VclPtr<ScrollBar> mpVerticalScrollBar;
+
+    /// Relative horizontal position of the visible area in the view.
+    double mnHorizontalPosition;
+    /// Relative vertical position of the visible area in the view.
+    double mnVerticalPosition;
+    /** The width and height of the border at the inside of the window which
+        when entered while in drag mode leads to a scrolling of the window.
+    */
+    Size maScrollBorder;
+    /** The only task of this little window is to paint the little square at
+        the bottom right corner left by the two scroll bars (when both are
+        visible).
+    */
+    VclPtr<ScrollBarBox> mpScrollBarFiller;
+
+    /** The auto scroll timer is used for keep scrolling the window when the
+        mouse reaches its border while dragging a selection.  When the mouse
+        is not moved the timer issues events to keep scrolling.
+    */
+    Timer maAutoScrollTimer;
+    Size maAutoScrollOffset;
+    bool mbIsAutoScrollActive;
+
+    /** The content window is the one whose view port is controlled by the
+        scroll bars.
+    */
+    VclPtr<sd::Window> mpContentWindow;
+
+    ::std::function<void ()> maAutoScrollFunctor;
+
+    void SetWindowOrigin (
+        double nHorizontalPosition,
+        double nVerticalPosition);
+
+    /** Determine the visibility of the scroll bars so that the window
+        content is not clipped in any dimension without showing a scroll
+        bar.
+        @param rAvailableArea
+            The area in which the scroll bars, the scroll bar filler, and
+            the SlideSorterView will be placed.
+        @return
+            The area that is enclosed by the scroll bars is returned.  It
+            will be filled with the SlideSorterView.
+    */
+    ::tools::Rectangle DetermineScrollBarVisibilities(
+        const ::tools::Rectangle& rAvailableArea,
+        const bool bIsHorizontalScrollBarAllowed,
+        const bool bIsVerticalScrollBarAllowed);
+
+    /** Typically called by DetermineScrollBarVisibilities() this method
+        tests a specific configuration of the two scroll bars being visible
+        or hidden.
+        @return
+            When the window content can be shown with only being clipped in
+            an orientation where the scroll bar would be shown then <TRUE/>
+            is returned.
+    */
+    bool TestScrollBarVisibilities (
+        bool bHorizontalScrollBarVisible,
+        bool bVerticalScrollBarVisible,
+        const ::tools::Rectangle& rAvailableArea);
+
+    void CalcAutoScrollOffset (const Point& rMouseWindowPosition);
+    bool RepeatAutoScroll();
+
+    DECL_LINK(HorizontalScrollBarHandler, ScrollBar*, void);
+    DECL_LINK(VerticalScrollBarHandler, ScrollBar*, void);
+    DECL_LINK(AutoScrollTimeoutHandler, Timer *, void);
+
+    void PlaceHorizontalScrollBar (const ::tools::Rectangle& aArea);
+    void PlaceVerticalScrollBar (const ::tools::Rectangle& aArea);
+    void PlaceFiller (const ::tools::Rectangle& aArea);
+};
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/controller/SlsSelectionFunction.hxx b/sd/source/ui/slidesorter/inc/controller/SlsSelectionFunction.hxx
new file mode 100644
index 000000000..7d80fbd26
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/controller/SlsSelectionFunction.hxx
@@ -0,0 +1,145 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <controller/SlsFocusManager.hxx>
+#include <fupoor.hxx>
+#include <memory>
+
+namespace sd::slidesorter
+{
+class SlideSorter;
+}
+
+struct AcceptDropEvent;
+
+namespace sd::slidesorter::controller
+{
+class SlideSorterController;
+
+class SelectionFunction final : public FuPoor
+{
+public:
+    SelectionFunction(const SelectionFunction&) = delete;
+    SelectionFunction& operator=(const SelectionFunction&) = delete;
+
+    static rtl::Reference<FuPoor> Create(SlideSorter& rSlideSorter, SfxRequest& rRequest);
+
+    // Mouse- & Key-Events
+    virtual bool KeyInput(const KeyEvent& rKEvt) override;
+    virtual bool MouseMove(const MouseEvent& rMEvt) override;
+    virtual bool MouseButtonUp(const MouseEvent& rMEvt) override;
+    virtual bool MouseButtonDown(const MouseEvent& rMEvt) override;
+
+    /// Forward to the clipboard manager.
+    virtual void DoCut() override;
+
+    /// Forward to the clipboard manager.
+    virtual void DoCopy() override;
+
+    /// Forward to the clipboard manager.
+    virtual void DoPaste() override;
+
+    /** is called when the current function should be aborted. <p>
+        This is used when a function gets a KEY_ESCAPE but can also
+        be called directly.
+
+        @returns
+            true if an active function was aborted
+    */
+    virtual bool cancel() override;
+
+    void MouseDragged(const AcceptDropEvent& rEvent, const sal_Int8 nDragAction);
+
+    /** Turn of substitution display and insertion indicator.
+    */
+    void NotifyDragFinished();
+
+    class EventDescriptor;
+    class ModeHandler;
+    friend class ModeHandler;
+    enum Mode
+    {
+        NormalMode,
+        MultiSelectionMode,
+        DragAndDropMode
+    };
+    void SwitchToNormalMode();
+    void SwitchToDragAndDropMode(const Point& rMousePosition);
+    void SwitchToMultiSelectionMode(const Point& rMousePosition, const sal_uInt32 nEventCode);
+
+    void ResetShiftKeySelectionAnchor();
+    /** Special case handling for when the context menu is hidden.  This
+        method will reinitialize the current mouse position to prevent the
+        mouse motion during the time the context menu is displayed from
+        being interpreted as drag-and-drop start.
+    */
+    void ResetMouseAnchor();
+
+private:
+    SlideSorter& mrSlideSorter;
+    SlideSorterController& mrController;
+
+    SelectionFunction(SlideSorter& rSlideSorter, SfxRequest& rRequest);
+
+    virtual ~SelectionFunction() override;
+
+    /** Remember the slide where the shift key was pressed and started a
+        multiselection via keyboard.
+    */
+    sal_Int32 mnShiftKeySelectionAnchor;
+
+    /** The selection function can be in one of several mutually
+        exclusive modes.
+    */
+    std::shared_ptr<ModeHandler> mpModeHandler;
+
+    /** Make the slide nOffset slides away of the current one the new
+        current slide.  When the new index is outside the range of valid
+        page numbers it is clipped to that range.
+        @param nOffset
+            When nOffset is negative then go back.  When nOffset if positive go
+            forward.  When it is zero then ignore the call.
+    */
+    void GotoNextPage(int nOffset);
+
+    /** Make the slide with the given index the new current slide.
+        @param nIndex
+            Index of the new current slide.  When the new index is outside
+            the range of valid page numbers it is clipped to that range.
+    */
+    void GotoPage(int nIndex);
+
+    void ProcessMouseEvent(sal_uInt32 nEventType, const MouseEvent& rEvent);
+
+    // What follows are a couple of helper methods that are used by
+    // ProcessMouseEvent().
+
+    void ProcessEvent(EventDescriptor& rEvent);
+
+    void MoveFocus(const FocusManager::FocusMoveDirection eDirection, const bool bIsShiftDown,
+                   const bool bIsControlDown);
+
+    void SwitchMode(const std::shared_ptr<ModeHandler>& rpHandler);
+};
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/controller/SlsSelectionManager.hxx b/sd/source/ui/slidesorter/inc/controller/SlsSelectionManager.hxx
new file mode 100644
index 000000000..4f52d49e6
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/controller/SlsSelectionManager.hxx
@@ -0,0 +1,139 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <sal/types.h>
+#include <tools/link.hxx>
+#include <vector>
+#include <memory>
+
+class SdPage;
+
+namespace sd::slidesorter
+{
+class SlideSorter;
+}
+
+namespace sd::slidesorter::controller
+{
+class SlideSorterController;
+class SelectionObserver;
+
+/** This class is a part of the controller and handles the selection of
+    slides.
+    <p>It has methods to modify the selected slides (delete them or
+    move them to other places in the document), change the visible area so
+    to make the selected slides visible, tell listeners when the selection
+    changes.</p>
+*/
+class SelectionManager
+{
+public:
+    /** Create a new SelectionManager for the given slide sorter.
+    */
+    SelectionManager(SlideSorter& rSlideSorter);
+
+    ~SelectionManager();
+
+    /** Delete the currently selected slides.  When this method returns the
+        selection is empty.
+        @param bSelectFollowingPage
+            When <TRUE/> then after deleting the selected pages make the
+            slide after the last selected page the new current page.
+            When <FALSE/> then make the first slide before the selected
+            pages the new current slide.
+    */
+    void DeleteSelectedPages(const bool bSelectFollowingPage = true);
+
+    /** Call this method after the selection has changed (possible several
+        calls to the PageSelector) to invalidate the relevant slots and send
+        appropriate events.
+    */
+    void SelectionHasChanged();
+
+    /** Add a listener that is called when the selection of the slide sorter
+        changes.
+        @param rListener
+            When this method is called multiple times for the same listener
+            the second and all following calls are ignored.  Each listener
+            is added only once.
+    */
+    void AddSelectionChangeListener(const Link<LinkParamNone*, void>& rListener);
+
+    /** Remove a listener that was called when the selection of the slide
+        sorter changes.
+        @param rListener
+            It is safe to pass a listener that was not added are has been
+            removed previously.  Such calls are ignored.
+    */
+    void RemoveSelectionChangeListener(const Link<LinkParamNone*, void>& rListener);
+
+    /** Return the position where to insert pasted slides based on the
+        current selection.  When there is a selection then the insert
+        position is behind the last slide.  When the selection is empty then
+        most of the time the insert position is at the end of the document.
+        There is an exception right after the display of a popup-menu.  The
+        position of the associated insertion marker is stored here and reset
+        the next time the selection changes.
+    */
+    sal_Int32 GetInsertionPosition() const;
+
+    /** Store an insertion position temporarily.  It is reset when the
+        selection changes the next time.
+    */
+    void SetInsertionPosition(const sal_Int32 nInsertionPosition);
+
+    const std::shared_ptr<SelectionObserver>& GetSelectionObserver() const
+    {
+        return mpSelectionObserver;
+    }
+
+private:
+    SlideSorter& mrSlideSorter;
+    SlideSorterController& mrController;
+
+    ::std::vector<Link<LinkParamNone*, void>> maSelectionChangeListeners;
+
+    /** The insertion position is only temporarily valid.  Negative values
+        indicate that the explicit insertion position is not valid.  In this
+        case GetInsertionPosition() calculates it from the current selection.
+    */
+    sal_Int32 mnInsertionPosition;
+
+    std::shared_ptr<SelectionObserver> mpSelectionObserver;
+
+    /** Delete the given list of normal pages.  This method is a helper
+        function for DeleteSelectedPages().
+        @param rSelectedNormalPages
+            A list of normal pages.  Supplying master pages is an error.
+    */
+    void DeleteSelectedNormalPages(const ::std::vector<SdPage*>& rSelectedNormalPages);
+
+    /** Delete the given list of master pages.  This method is a helper
+        function for DeleteSelectedPages().
+        @param rSelectedMasterPages
+            A list of master pages.  Supplying normal pages is an error.
+    */
+    void DeleteSelectedMasterPages(const ::std::vector<SdPage*>& rSelectedMasterPages);
+};
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/controller/SlsSelectionObserver.hxx b/sd/source/ui/slidesorter/inc/controller/SlsSelectionObserver.hxx
new file mode 100644
index 000000000..11742b890
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/controller/SlsSelectionObserver.hxx
@@ -0,0 +1,77 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <sal/types.h>
+#include <memory>
+#include <vector>
+
+namespace sd::slidesorter
+{
+class SlideSorter;
+}
+
+class SdrPage;
+class SdPage;
+
+namespace sd::slidesorter::controller
+{
+/** Observe insertions and deletions of pages between calls to
+    StartObservation() and EndObservation().  When the later is called
+    the selection is set to just the newly inserted pages.
+*/
+class SelectionObserver final
+{
+public:
+    SelectionObserver(SlideSorter& rSlideSorter);
+    ~SelectionObserver();
+
+    void NotifyPageEvent(const SdrPage* pPage);
+    void StartObservation();
+    void AbortObservation();
+    void EndObservation();
+
+    /** Use this little class instead of calling StartObservation and
+        EndObservation directly so that EndObservation is not forgotten or
+        omitted due to an exception or some break or return in the middle of
+        code.
+    */
+    class Context
+    {
+    public:
+        Context(SlideSorter const& rSlideSorter);
+        ~Context() COVERITY_NOEXCEPT_FALSE;
+        void Abort();
+
+    private:
+        std::shared_ptr<SelectionObserver> mpSelectionObserver;
+    };
+
+private:
+    SlideSorter& mrSlideSorter;
+    bool mbIsObservationActive;
+    bool mbPageEventOccurred;
+
+    ::std::vector<const SdPage*> maInsertedPages;
+};
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/controller/SlsSlotManager.hxx b/sd/source/ui/slidesorter/inc/controller/SlsSlotManager.hxx
new file mode 100644
index 000000000..57de8422a
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/controller/SlsSlotManager.hxx
@@ -0,0 +1,98 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+#pragma once
+
+#include <model/SlsSharedPageDescriptor.hxx>
+#include <tools/link.hxx>
+#include <rtl/ustring.hxx>
+
+class AbstractSvxNameDialog;
+class SfxItemSet;
+class SfxRequest;
+
+namespace sd::slidesorter
+{
+class SlideSorter;
+}
+
+namespace sd::slidesorter::controller
+{
+/** This manager takes over the work of handling slot calls from the
+    controller of the slide sorter.
+*/
+class SlotManager
+{
+public:
+    /** Create a new slot manager that handles slot calls for the controller
+        of a slide sorter.
+        @param rController
+            The controller for which to handle the slot calls.
+    */
+    SlotManager(SlideSorter& rSlideSorter);
+
+    void FuTemporary(SfxRequest& rRequest);
+    void FuPermanent(SfxRequest& rRequest);
+    void FuSupport(SfxRequest& rRequest);
+    void GetMenuState(SfxItemSet& rSet);
+    void GetClipboardState(SfxItemSet& rSet);
+    void GetStatusBarState(SfxItemSet& rSet);
+    void ExecCtrl(SfxRequest& rRequest);
+    void GetAttrState(SfxItemSet& rSet);
+
+    /** Exclude or include one slide or all selected slides.
+        @param rpDescriptor
+            When the pointer is empty then apply the new state to all
+            selected pages.  Otherwise apply the new state to just the
+            specified state.
+    */
+    void ChangeSlideExclusionState(const model::SharedPageDescriptor& rpDescriptor,
+                                   const bool bExcludeSlide);
+
+    /** Call this after a change from normal mode to master mode or back.
+        The affected slots are invalidated.
+    */
+    void NotifyEditModeChange();
+
+private:
+    /// The controller for which we manage the slot calls.
+    SlideSorter& mrSlideSorter;
+
+    /** The implementation is a copy of the code for SID_RENAMEPAGE in
+        drviews2.cxx.
+    */
+    void RenameSlide(const SfxRequest& rRequest);
+    DECL_LINK(RenameSlideHdl, AbstractSvxNameDialog&, bool);
+    DECL_STATIC_LINK(SlotManager, RenameSlideTooltipHdl, AbstractSvxNameDialog&, OUString);
+    bool RenameSlideFromDrawViewShell(sal_uInt16 nPageId, const OUString& rName);
+
+    /** Handle SID_INSERTPAGE slot calls.
+    */
+    void InsertSlide(SfxRequest& rRequest);
+
+    void DuplicateSelectedSlides(SfxRequest& rRequest);
+
+    /** Use one of several ways to determine where to insert a new page.
+        This can be the current selection or the insertion indicator.
+    */
+    sal_Int32 GetInsertionPosition() const;
+};
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/controller/SlsTransferableData.hxx b/sd/source/ui/slidesorter/inc/controller/SlsTransferableData.hxx
new file mode 100644
index 000000000..863c2fe73
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/controller/SlsTransferableData.hxx
@@ -0,0 +1,78 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <sdxfer.hxx>
+
+#include <vcl/bitmapex.hxx>
+
+#include <vector>
+
+class SdDrawDocument;
+namespace sd::slidesorter { class SlideSorterViewShell; }
+
+namespace sd::slidesorter::controller {
+
+/** Represent previews and other information so that they can be
+    attached to an existing transferable.
+*/
+class TransferableData final
+    : public SdTransferable::UserData,
+      public SfxListener
+{
+public:
+    class Representative
+    {
+    public:
+        Representative (const BitmapEx& rBitmap, const bool bIsExcluded)
+            : maBitmap(rBitmap), mbIsExcluded(bIsExcluded) {}
+
+        BitmapEx maBitmap;
+        bool mbIsExcluded;
+    };
+
+    static rtl::Reference<SdTransferable> CreateTransferable (
+        SdDrawDocument* pSrcDoc,
+        SlideSorterViewShell* pViewShell,
+        ::std::vector<TransferableData::Representative>&& rRepresentatives);
+
+    static std::shared_ptr<TransferableData> GetFromTransferable (const SdTransferable* pTransferable);
+
+    TransferableData (
+        SlideSorterViewShell* pViewShell,
+        ::std::vector<TransferableData::Representative>&& rRepresentatives);
+    virtual ~TransferableData() override;
+
+    const ::std::vector<Representative>& GetRepresentatives() const { return maRepresentatives;}
+
+    /** Return the view shell for which the transferable was created.
+    */
+    SlideSorterViewShell* GetSourceViewShell() const { return mpViewShell;}
+
+private:
+    SlideSorterViewShell* mpViewShell;
+    const ::std::vector<Representative> maRepresentatives;
+
+    virtual void Notify (SfxBroadcaster& rBroadcaster, const SfxHint& rHint) override;
+};
+
+} // end of namespace ::sd::slidesorter::controller
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/controller/SlsVisibleAreaManager.hxx b/sd/source/ui/slidesorter/inc/controller/SlsVisibleAreaManager.hxx
new file mode 100644
index 000000000..d9f5845af
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/controller/SlsVisibleAreaManager.hxx
@@ -0,0 +1,90 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <model/SlsSharedPageDescriptor.hxx>
+#include <optional>
+#include <tools/gen.hxx>
+#include <vector>
+
+namespace sd::slidesorter
+{
+class SlideSorter;
+}
+
+namespace sd::slidesorter::controller
+{
+/** Manage requests for scrolling page objects into view.
+*/
+class VisibleAreaManager
+{
+public:
+    explicit VisibleAreaManager(SlideSorter& rSlideSorter);
+    ~VisibleAreaManager();
+    VisibleAreaManager(const VisibleAreaManager&) = delete;
+    VisibleAreaManager& operator=(const VisibleAreaManager&) = delete;
+
+    void ActivateCurrentSlideTracking();
+    void DeactivateCurrentSlideTracking();
+    bool IsCurrentSlideTrackingActive() const { return mbIsCurrentSlideTrackingActive; }
+
+    /** Request the current slide to be moved into the visible area.
+        This request is only obeyed when the current slide tracking is
+        active.
+        @see ActivateCurrentSlideTracking() and DeactivateCurrentSlideTracking()
+    */
+    void RequestCurrentSlideVisible();
+
+    /** Request to make the specified page object visible.
+    */
+    void RequestVisible(const model::SharedPageDescriptor& rpDescriptor, const bool bForce = false);
+
+    /** Temporarily disable the update of the visible area.
+    */
+    class TemporaryDisabler
+    {
+    public:
+        explicit TemporaryDisabler(SlideSorter const& rSlideSorter);
+        ~TemporaryDisabler();
+
+    private:
+        VisibleAreaManager& mrVisibleAreaManager;
+    };
+
+private:
+    SlideSorter& mrSlideSorter;
+
+    /** List of rectangle that someone wants to be moved into the visible
+        area.
+        Cleared on every call to ForgetVisibleRequests() and MakeVisible().
+    */
+    ::std::vector<::tools::Rectangle> maVisibleRequests;
+
+    Point maRequestedVisibleTopLeft;
+    bool mbIsCurrentSlideTrackingActive;
+    int mnDisableCount;
+
+    void MakeVisible();
+    ::std::optional<Point> GetRequestedTopLeft() const;
+};
+
+} // end of namespace ::sd::slidesorter::view
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/model/SlideSorterModel.hxx b/sd/source/ui/slidesorter/inc/model/SlideSorterModel.hxx
new file mode 100644
index 000000000..90223a1bc
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/model/SlideSorterModel.hxx
@@ -0,0 +1,227 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <model/SlsSharedPageDescriptor.hxx>
+#include <pres.hxx>
+#include <osl/mutex.hxx>
+#include <vcl/region.hxx>
+#include <com/sun/star/uno/Reference.hxx>
+#include <vector>
+
+class SdDrawDocument;
+class SdrPage;
+class SdPage;
+namespace sd::slidesorter
+{
+class SlideSorter;
+}
+namespace com::sun::star::container
+{
+class XIndexAccess;
+}
+namespace com::sun::star::drawing
+{
+class XDrawPage;
+}
+
+namespace sd::slidesorter::model
+{
+inline sal_Int32 FromCoreIndex(const sal_uInt16 nCoreIndex) { return (nCoreIndex - 1) / 2; }
+
+/** The model of the slide sorter gives access to the slides that are to be
+    displayed in the slide sorter view.  Via the SetDocumentSlides() method
+    this set of slides can be modified (but do not call it directly, use
+    SlideSorterController::SetDocumentSlides() instead.)
+*/
+class SlideSorterModel final
+{
+public:
+    SlideSorterModel(SlideSorter& rSlideSorter);
+
+    ~SlideSorterModel();
+    void Dispose();
+
+    /** This method is present to let the view create a ShowView for
+        displaying slides.
+    */
+    SdDrawDocument* GetDocument();
+
+    /** Set a new edit mode and return whether the edit mode really
+        has been changed.  When the edit mode is changed then the
+        previous page descriptor list is replaced by a new one which
+        has to be repainted.
+        @return
+            A return value of <TRUE/> indicates that the edit mode has
+            changed and thus the page descriptor list has been set up
+            to reflect that change.  A repaint is necessary.
+    */
+    bool SetEditMode(EditMode eEditMode);
+
+    EditMode GetEditMode() const { return meEditMode; }
+
+    /** Return the number of slides in the document regardless of whether
+        they are visible or not or whether they are hidden or not.
+        The number of slides depends on the set of slides available through
+        the XIndexAccess given to SetDocumentSlides().
+    */
+    sal_Int32 GetPageCount() const;
+
+    /** Return a page descriptor for the page with the specified index.
+        Page descriptors are created on demand.  The page descriptor is
+        found (or not found) in constant time.
+        @param nPageIndex
+            The index of the requested slide.  The valid values
+            are 0 to GetPageCount()-1.
+        @param bCreate
+            When <TRUE/> and the requested page descriptor is missing then
+            it is created.  When <FALSE/> then an empty reference is
+            returned for missing descriptors.
+        @return
+            When the given index is not valid, i.e. lower than zero or
+            larger than or equal to the number of pages then an empty
+            reference is returned. Note that the page count may change
+            between calls to GetPageCount() and GetPageDescriptor().
+    */
+    SharedPageDescriptor GetPageDescriptor(const sal_Int32 nPageIndex,
+                                           const bool bCreate = true) const;
+
+    /** Return a page descriptor for the given XDrawPage.  Page descriptors
+        are created on demand.  The page descriptor is found (or not found)
+        in (at most) linear time.  Note that all page descriptors in front of
+        the one associated with the given XDrawPage are created when not yet
+        present. When the XDrawPage is not found then all descriptors are
+        created.
+        @return
+            Returns the index to the requested page descriptor or -1 when
+            there is no such page descriptor.
+    */
+    sal_Int32 GetIndex(const css::uno::Reference<css::drawing::XDrawPage>& rxSlide) const;
+
+    /** Return a page descriptor for the given SdrPage.  Page descriptors
+        are created on demand.  The page descriptor is found (or not found)
+        in (at most) linear time.  Note that all page descriptors in front of
+        the one associated with the given XDrawPage are created when not yet
+        present. When the SdrPage is not found then all descriptors are
+        created.
+        @return
+            Returns the index to the requested page descriptor or -1 when
+            there is no such page descriptor.
+    */
+    sal_Int32 GetIndex(const SdrPage* pPage) const;
+
+    /** Return an index for accessing an SdrModel that corresponds to the
+        given SlideSorterModel index.  In many cases we just have to apply
+        the n*2+1 magic.  Only when a special model is set, like a custom
+        slide show, then the returned value is different.
+    */
+    sal_uInt16 GetCoreIndex(const sal_Int32 nIndex) const;
+
+    /** Call this method after the document has changed its structure.  This
+        will get the model in sync with the SdDrawDocument.  This method
+        tries not to throw away too much information already gathered.  This
+        is especially important for previews of complex pages that take some
+        time to create.
+    */
+    void Resync();
+
+    /** Delete all descriptors that currently are in the container.  The size
+        of the container, however, is not altered.  Use the AdaptSize
+        method for that.
+    */
+    void ClearDescriptorList();
+
+    /** Set the selection of the document to exactly that of the called model.
+    */
+    void SynchronizeDocumentSelection();
+
+    /** Set the selection of the called model to exactly that of the document.
+    */
+    void SynchronizeModelSelection();
+
+    /** Return the mutex so that the caller can lock it and then safely
+        access the model.
+    */
+    ::osl::Mutex& GetMutex() { return maMutex; }
+
+    /** Set the XIndexAccess from which the called SlideSorterModel takes
+        its pages.
+        @param rxSlides
+            The set of slides accessible through this XIndexAccess are not
+            necessarily the same as the ones of the XModel of the
+            XController (although it typically is a subset).
+    */
+    void SetDocumentSlides(const css::uno::Reference<css::container::XIndexAccess>& rxSlides);
+
+    /** Return the set of pages that is currently displayed by the slide sorter.
+    */
+    css::uno::Reference<css::container::XIndexAccess> GetDocumentSlides() const;
+
+    /** This method is called when the edit mode has changed.  It calls
+        SetDocumentSlides() with the set of slides or master pages obtained
+        from the model of the XController.
+    */
+    void UpdatePageList();
+
+    bool IsReadOnly() const;
+
+    /** The current selection is saved by copying the ST_Selected state into
+        ST_WasSelected for slides.
+    */
+    void SaveCurrentSelection();
+
+    /** The current selection is restored from the ST_WasSelected state from
+        the slides.
+        @returns
+            The returned region has to be repainted to reflect the updated
+            selection states.
+    */
+    vcl::Region RestoreSelection();
+
+    /** Typically called from controller::Listener this method handles the
+        insertion and deletion of single pages.
+        @return
+            Returns <TRUE/> when the given page is relevant for the current
+            page kind and edit mode.
+    */
+    bool NotifyPageEvent(const SdrPage* pPage);
+
+private:
+    mutable ::osl::Mutex maMutex;
+    SlideSorter& mrSlideSorter;
+    css::uno::Reference<css::container::XIndexAccess> mxSlides;
+    EditMode meEditMode;
+    mutable ::std::vector<SharedPageDescriptor> maPageDescriptors;
+
+    /** Resize the descriptor container according to current values of
+        page kind and edit mode.
+    */
+    void AdaptSize();
+
+    SdPage* GetPage(const sal_Int32 nCoreIndex) const;
+    void InsertSlide(SdPage* pPage, bool bMarkSelected);
+    // return if this page was marked as selected before being removed
+    bool DeleteSlide(const SdPage* pPage);
+    void UpdateIndices(const sal_Int32 nFirstIndex);
+};
+
+} // end of namespace ::sd::slidesorter::model
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/model/SlsEnumeration.hxx b/sd/source/ui/slidesorter/inc/model/SlsEnumeration.hxx
new file mode 100644
index 000000000..289f85911
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/model/SlsEnumeration.hxx
@@ -0,0 +1,44 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <memory>
+
+namespace sd::slidesorter::model
+{
+/** Interface to generic enumerations.  Designed to operate on shared
+    pointers.  Therefore GetNextElement() returns T and not T&.
+*/
+template <class T> class Enumeration
+{
+public:
+    virtual ~Enumeration() {}
+
+    virtual bool HasMoreElements() const = 0;
+    /** Returns T instead of T& so that it can handle shared pointers.
+    */
+    virtual T GetNextElement() = 0;
+    virtual void Rewind() = 0;
+    virtual ::std::unique_ptr<Enumeration<T>> Clone() = 0;
+};
+
+} // end of namespace ::sd::slidesorter::model
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/model/SlsPageDescriptor.hxx b/sd/source/ui/slidesorter/inc/model/SlsPageDescriptor.hxx
new file mode 100644
index 000000000..4f3be3b42
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/model/SlsPageDescriptor.hxx
@@ -0,0 +1,144 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <model/SlsVisualState.hxx>
+#include <tools/gen.hxx>
+#include <com/sun/star/uno/Reference.hxx>
+
+#include <memory>
+
+namespace com::sun::star::drawing { class XDrawPage; }
+
+class SdPage;
+class SdrPage;
+
+namespace sd::slidesorter::model {
+
+/** Each PageDescriptor object represents the preview of one draw page,
+    slide, or master page of a Draw or Impress document as they are displayed
+    in the slide sorter.  This class gives access to some associated
+    information like prerendered preview or position on the screen.
+
+    <p>Bounding boxes of page objects come in four varieties:
+    Model and screen/pixel coordinates and the bounding boxes of the actual
+    page objects and the larger bounding boxes that include page names and
+    fade symbol.</p>
+*/
+class PageDescriptor
+    : public ::std::enable_shared_from_this<PageDescriptor>
+{
+public:
+    /** Create a PageDescriptor for the given SdPage object.
+        @param rxPage
+            The page that is represented by the new PageDescriptor object.
+        @param pPage
+            The page pointer can in some situations not be detected from
+            rxPage, e.g. after undo of page deletion.  Therefore supply it
+            separately.
+        @param nIndex
+            This index is displayed in the view as page number.  It is not
+            necessarily the page index (not even when you add or subtract 1
+            or use (x-1)/2 magic).
+    */
+    PageDescriptor (
+        const css::uno::Reference<css::drawing::XDrawPage>& rxPage,
+        SdPage* pPage,
+        const sal_Int32 nIndex);
+
+    ~PageDescriptor();
+
+    /** Return the page that is represented by the descriptor as SdPage pointer .
+    */
+    SdPage* GetPage() const { return mpPage;}
+
+    /** Return the page that is represented by the descriptor as XDrawPage reference.
+    */
+    const css::uno::Reference<css::drawing::XDrawPage>& GetXDrawPage() const { return mxPage;}
+
+    /** Returns the index of the page as it is displayed in the view as page
+        number.  The value may differ from the index returned by the
+        XDrawPage when there are hidden slides and the XIndexAccess used to
+        access the model filters them out.
+    */
+    sal_Int32 GetPageIndex() const { return mnIndex;}
+    void SetPageIndex (const sal_Int32 nIndex);
+
+    bool UpdateMasterPage();
+    bool UpdateTransitionFlag();
+
+    enum State { ST_Visible, ST_Selected, ST_WasSelected,
+                 ST_Focused, ST_MouseOver, ST_Current, ST_Excluded };
+
+    bool HasState (const State eState) const;
+
+    bool SetState (const State eState, const bool bStateValue);
+
+    /** Set the internal mbIsSelected flag to the selection state of the
+        page.  Use this method to synchronize a page descriptor with the
+        page it describes and determine whether a redraw to update the
+        selection indicator is necessary.
+        @return
+            When the two selection states were different <TRUE/> is
+            returned.  When they were the same this method returns
+            <FALSE/>.
+    */
+    bool GetCoreSelection();
+
+    /** Set the selection flags of the SdPage objects to the corresponding
+        selection states of the page descriptors.
+    */
+    void SetCoreSelection();
+
+    VisualState& GetVisualState() { return maVisualState;}
+
+    ::tools::Rectangle GetBoundingBox() const;
+    Point GetLocation (const bool bIgnoreLocation) const;
+    void SetBoundingBox (const ::tools::Rectangle& rBoundingBox);
+
+private:
+    SdPage* mpPage;
+    css::uno::Reference<css::drawing::XDrawPage> mxPage;
+    SdrPage const* mpMasterPage;
+
+    /** This index is displayed as page number in the view.  It may or may
+        not be the actual page index.
+    */
+    sal_Int32 mnIndex;
+
+    ::tools::Rectangle maBoundingBox;
+    VisualState maVisualState;
+
+    bool mbIsSelected : 1;
+    bool mbWasSelected : 1;
+    bool mbIsVisible : 1;
+    bool mbIsFocused : 1;
+    bool mbIsCurrent : 1;
+    bool mbIsMouseOver : 1;
+    bool mbHasTransition : 1;
+
+    PageDescriptor (const PageDescriptor& rDescriptor) = delete;
+
+    PageDescriptor& operator= (const PageDescriptor& rDescriptor) = delete;
+};
+
+} // end of namespace ::sd::slidesorter::model
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/model/SlsPageEnumeration.hxx b/sd/source/ui/slidesorter/inc/model/SlsPageEnumeration.hxx
new file mode 100644
index 000000000..6901a9ff1
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/model/SlsPageEnumeration.hxx
@@ -0,0 +1,95 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <model/SlsEnumeration.hxx>
+#include <model/SlsSharedPageDescriptor.hxx>
+
+#include <functional>
+#include <memory>
+
+namespace sd::slidesorter::model
+{
+class SlideSorterModel;
+
+/** Public class of page enumerations that delegates its calls to an
+    implementation object that can filter pages by using a given predicate.
+
+    @see PageEnumerationProvider
+        The PageEnumerationProvider has methods for creating different types
+        of page enumerations.
+*/
+class PageEnumeration final : public Enumeration<SharedPageDescriptor>
+{
+public:
+    /** Create a new page enumeration that enumerates a subset of the pages
+        of the given model.
+        @param rModel
+            The new page enumeration enumerates the pages of this model.
+        @param rPredicate
+            This predicate determines which pages to include in the
+            enumeration.  Pages for which rPredicate returns <FALSE/> are
+            exclude.
+    */
+    typedef ::std::function<bool(const SharedPageDescriptor&)> PagePredicate;
+    static PageEnumeration Create(const SlideSorterModel& rModel, const PagePredicate& rPredicate);
+
+    /** This copy constructor creates a copy of the given enumeration.
+    */
+    PageEnumeration(const PageEnumeration& rEnumeration);
+
+    virtual ~PageEnumeration() override;
+
+    /** Create and return an exact copy of the called object.
+    */
+    virtual ::std::unique_ptr<Enumeration<SharedPageDescriptor>> Clone() override;
+
+    PageEnumeration& operator=(const PageEnumeration& rEnumeration);
+
+    /** Return <TRUE/> when the enumeration has more elements, i.e. it is
+        save to call GetNextElement() at least one more time.
+    */
+    virtual bool HasMoreElements() const override;
+
+    /** Return the next element of the enumeration.  Call the
+        HasMoreElements() before to make sure that there exists at least one
+        more element.  Calling this method with HasMoreElements() returning
+        <FALSE/> is an error.
+    */
+    virtual SharedPageDescriptor GetNextElement() override;
+
+    /** Rewind the enumeration so that the next call to GetNextElement()
+        will return its first element.
+    */
+    virtual void Rewind() override;
+
+private:
+    /// Implementation object.
+    ::std::unique_ptr<Enumeration<SharedPageDescriptor>> mpImpl;
+
+    /** This constructor expects an implementation object that holds
+        the predicate that filters the pages.
+    */
+    PageEnumeration(::std::unique_ptr<Enumeration<SharedPageDescriptor>>&& pImpl);
+};
+
+} // end of namespace ::sd::slidesorter::model
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/model/SlsPageEnumerationProvider.hxx b/sd/source/ui/slidesorter/inc/model/SlsPageEnumerationProvider.hxx
new file mode 100644
index 000000000..b6de98d13
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/model/SlsPageEnumerationProvider.hxx
@@ -0,0 +1,51 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <model/SlsPageEnumeration.hxx>
+
+namespace sd::slidesorter::model
+{
+class SlideSorterModel;
+
+/** Collection of methods that create enumeration of slides.
+*/
+class PageEnumerationProvider
+{
+public:
+    /** The returned enumeration of slides iterates over all slides of the
+        given model.
+    */
+    static PageEnumeration CreateAllPagesEnumeration(const SlideSorterModel& rModel);
+
+    /** The returned enumeration of slides iterates over the currently
+        selected slides of the given model.
+    */
+    static PageEnumeration CreateSelectedPagesEnumeration(const SlideSorterModel& rModel);
+
+    /** The returned enumeration of slides iterates over the slides
+        (partially) inside the visible area.
+    */
+    static PageEnumeration CreateVisiblePagesEnumeration(const SlideSorterModel& rModel);
+};
+
+} // end of namespace ::sd::slidesorter::model
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/model/SlsSharedPageDescriptor.hxx b/sd/source/ui/slidesorter/inc/model/SlsSharedPageDescriptor.hxx
new file mode 100644
index 000000000..6ee1e2b22
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/model/SlsSharedPageDescriptor.hxx
@@ -0,0 +1,32 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <memory>
+
+namespace sd::slidesorter::model
+{
+class PageDescriptor;
+
+typedef std::shared_ptr<PageDescriptor> SharedPageDescriptor;
+
+} // end of namespace ::sd::slidesorter::model
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/model/SlsVisualState.hxx b/sd/source/ui/slidesorter/inc/model/SlsVisualState.hxx
new file mode 100644
index 000000000..89eae16ca
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/model/SlsVisualState.hxx
@@ -0,0 +1,47 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <sal/types.h>
+#include <tools/gen.hxx>
+
+namespace sd::slidesorter::model
+{
+/** This class gives access to values related to the visualization of page
+    objects.  This includes animation state when blending from one state to
+    another.
+*/
+class VisualState
+{
+public:
+    VisualState(const sal_Int32 nPageId);
+
+    const Point& GetLocationOffset() const { return maLocationOffset; }
+    void SetLocationOffset(const Point& rPoint);
+
+    sal_Int32 mnPageId; // For debugging
+
+private:
+    Point maLocationOffset;
+};
+
+} // end of namespace ::sd::slidesorter::model
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/view/SlideSorterView.hxx b/sd/source/ui/slidesorter/inc/view/SlideSorterView.hxx
new file mode 100644
index 000000000..0f3493ab3
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/view/SlideSorterView.hxx
@@ -0,0 +1,225 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <model/SlsPageDescriptor.hxx>
+#include <model/SlsSharedPageDescriptor.hxx>
+#include <view/SlsLayouter.hxx>
+#include <view/SlsILayerPainter.hxx>
+#include <o3tl/deleter.hxx>
+
+#include <View.hxx>
+#include <tools/gen.hxx>
+#include <vcl/region.hxx>
+#include <memory>
+
+namespace sd::slidesorter::cache { class PageCache; }
+namespace sd::slidesorter::model { class SlideSorterModel; }
+namespace sd { class Window; }
+namespace sd::slidesorter { class SlideSorter; }
+namespace sd::slidesorter::view {
+
+class LayeredDevice;
+class PageObjectPainter;
+class ToolTip;
+
+class SlideSorterView final
+    : public sd::View
+{
+public:
+
+    /** Create a new view for the slide sorter.
+        @param rViewShell
+            This reference is simply passed to the base class and not used
+            by this class.
+
+    */
+    explicit SlideSorterView (SlideSorter& rSlideSorter);
+    void Init();
+
+    virtual ~SlideSorterView() override;
+    void Dispose();
+
+    SlideSorterView(const SlideSorterView&) = delete;
+    SlideSorterView& operator=(const SlideSorterView&) = delete;
+
+    /** Set the general way of layouting the page objects.  Note that this
+        method does not trigger any repaints or layouts.
+    */
+    bool SetOrientation (const Layouter::Orientation eOrientation);
+    Layouter::Orientation GetOrientation() const { return meOrientation;}
+
+    void RequestRepaint();
+    void RequestRepaint (const model::SharedPageDescriptor& rDescriptor);
+    void RequestRepaint (const ::tools::Rectangle& rRepaintBox);
+    void RequestRepaint (const vcl::Region& rRepaintRegion);
+
+    ::tools::Rectangle GetModelArea() const;
+
+    /** Return the index of the page that is rendered at the given position.
+        @param rPosition
+            The position is expected to be in pixel coordinates.
+        @return
+            The returned index is -1 when there is no page object at the
+            given position.
+    */
+    sal_Int32 GetPageIndexAtPoint (const Point& rPosition) const;
+
+    view::Layouter& GetLayouter();
+
+    virtual void ModelHasChanged() override;
+
+    /** This method is typically called before a model change takes place.
+        All references to model data are released.  PostModelChange() has to
+        be called to complete the handling of the model change.  When the
+        calls to Pre- and PostModelChange() are very close to each other you
+        may call HandleModelChange() instead.
+    */
+    void PreModelChange();
+
+    /** This method is typically called after a model change took place.
+        References to model data are re-allocated.  Call this method only
+        after PreModelChange() has been called.
+    */
+    void PostModelChange();
+
+    /** This method is a convenience function that simply calls
+        PreModelChange() and then PostModelChange().
+    */
+    void HandleModelChange();
+
+    void HandleDrawModeChange();
+
+    void Resize();
+    virtual void CompleteRedraw (
+        OutputDevice* pDevice,
+        const vcl::Region& rPaintArea,
+        sdr::contact::ViewObjectContactRedirector* pRedirector = nullptr) override;
+    void Paint (OutputDevice& rDevice, const ::tools::Rectangle& rRepaintArea);
+
+    virtual void ConfigurationChanged (
+        utl::ConfigurationBroadcaster* pBroadcaster,
+        ConfigurationHints nHint) override;
+
+    void HandleDataChangeEvent();
+
+    void Layout();
+    /** This tells the view that it has to re-determine the visibility of
+        the page objects before painting them the next time.
+    */
+    void InvalidatePageObjectVisibilities();
+
+    std::shared_ptr<cache::PageCache> const & GetPreviewCache();
+
+    /** Return the range of currently visible page objects including the
+        first and last one in that range.
+        @return
+            The returned pair of page object indices is empty when the
+            second index is lower than the first.
+    */
+    Range const & GetVisiblePageRange();
+
+    /** Add a shape to the page.  Typically used from inside
+        PostModelChange().
+    */
+    //    void AddSdrObject (SdrObject& rObject);
+
+    /** Add a listener that is called when the set of visible slides.
+        @param rListener
+            When this method is called multiple times for the same listener
+            the second and all following calls are ignored.  Each listener
+            is added only once.
+    */
+    void AddVisibilityChangeListener (const Link<LinkParamNone*,void>& rListener);
+
+    /** Remove a listener that is called when the set of visible slides changes.
+        @param rListener
+            It is safe to pass a listener that was not added or has been
+            removed previously.  Such calls are ignored.
+    */
+    void RemoveVisibilityChangeListener (const Link<LinkParamNone*,void>& rListener);
+
+    /** The page under the mouse is not highlighted in some contexts.  Call
+        this method on context changes.
+    */
+    void UpdatePageUnderMouse ();
+    void UpdatePageUnderMouse (const Point& rMousePosition);
+    void SetPageUnderMouse (const model::SharedPageDescriptor& rpDescriptor);
+
+    bool SetState (
+        const model::SharedPageDescriptor& rpDescriptor,
+        const model::PageDescriptor::State eState,
+        const bool bStateValue);
+
+    void UpdateOrientation();
+
+    std::shared_ptr<PageObjectPainter> const & GetPageObjectPainter();
+    const std::shared_ptr<LayeredDevice>& GetLayeredDevice() const { return mpLayeredDevice;}
+
+    class DrawLock
+    {
+    public:
+        DrawLock (SlideSorter const & rSlideSorter);
+        ~DrawLock();
+        /** When the DrawLock is disposed then it will not request a repaint
+            on destruction.
+        */
+        void Dispose();
+    private:
+        view::SlideSorterView& mrView;
+        VclPtr<sd::Window> mpWindow;
+    };
+
+    ToolTip& GetToolTip() const;
+
+    virtual void DragFinished (sal_Int8 nDropAction) override;
+
+private:
+    SlideSorter& mrSlideSorter;
+    model::SlideSorterModel& mrModel;
+    bool mbIsDisposed;
+    ::std::unique_ptr<Layouter> mpLayouter;
+    bool mbPageObjectVisibilitiesValid;
+    std::shared_ptr<cache::PageCache> mpPreviewCache;
+    std::shared_ptr<LayeredDevice> mpLayeredDevice;
+    Range maVisiblePageRange;
+    Size maPreviewSize;
+    bool mbPreciousFlagUpdatePending;
+    Layouter::Orientation meOrientation;
+    model::SharedPageDescriptor mpPageUnderMouse;
+    std::shared_ptr<PageObjectPainter> mpPageObjectPainter;
+    vcl::Region maRedrawRegion;
+    SharedILayerPainter mpBackgroundPainter;
+    std::unique_ptr<ToolTip, o3tl::default_delete<ToolTip>> mpToolTip;
+    bool mbIsRearrangePending;
+    ::std::vector<Link<LinkParamNone*,void>> maVisibilityChangeListeners;
+
+    /** Determine the visibility of all page objects.
+    */
+    void DeterminePageObjectVisibilities();
+
+    void UpdatePreciousFlags();
+    void RequestRearrange();
+    void Rearrange();
+};
+
+} // end of namespace ::sd::slidesorter::view
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/view/SlsILayerPainter.hxx b/sd/source/ui/slidesorter/inc/view/SlsILayerPainter.hxx
new file mode 100644
index 000000000..57b90af0a
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/view/SlsILayerPainter.hxx
@@ -0,0 +1,53 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <memory>
+
+class OutputDevice;
+namespace tools { class Rectangle; }
+
+namespace sd::slidesorter::view {
+
+class ILayerInvalidator
+{
+public:
+    virtual ~ILayerInvalidator() {}
+
+    virtual void Invalidate (const ::tools::Rectangle& rInvalidationBox) = 0;
+};
+typedef std::shared_ptr<ILayerInvalidator> SharedILayerInvalidator;
+
+class ILayerPainter
+{
+public:
+    virtual ~ILayerPainter() {}
+
+    virtual void SetLayerInvalidator (
+        const SharedILayerInvalidator& rpInvalidator) = 0;
+    virtual void Paint (
+        OutputDevice& rDevice,
+        const ::tools::Rectangle& rRepaintArea) = 0;
+};
+typedef std::shared_ptr<ILayerPainter> SharedILayerPainter;
+
+} // end of namespace ::sd::slidesorter::view
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/view/SlsInsertAnimator.hxx b/sd/source/ui/slidesorter/inc/view/SlsInsertAnimator.hxx
new file mode 100644
index 000000000..c74d06cb9
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/view/SlsInsertAnimator.hxx
@@ -0,0 +1,59 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <controller/SlsAnimator.hxx>
+#include <memory>
+
+namespace sd::slidesorter::view
+{
+class InsertPosition;
+
+/** Animate the positions of page objects to make room at the insert
+    position while a move or copy operation takes place.
+*/
+class InsertAnimator
+{
+public:
+    explicit InsertAnimator(SlideSorter& rSlideSorter);
+    InsertAnimator(const InsertAnimator&) = delete;
+    InsertAnimator& operator=(const InsertAnimator&) = delete;
+
+    /** Set the position at which we have to make room for the display of an
+        icon.
+    */
+    void SetInsertPosition(const InsertPosition& rInsertPosition);
+
+    /** Restore the normal position of all page objects.
+        @param eMode
+            This flag controls whether to start an animation that ends in the
+            normal positions of all slides (AM_Animated) or to restore the
+            normal positions immediately (AM_Immediate).
+    */
+    void Reset(const controller::Animator::AnimationMode eMode);
+
+private:
+    class Implementation;
+    std::shared_ptr<Implementation> mpImplementation;
+};
+
+} // end of namespace ::sd::slidesorter::view
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/view/SlsInsertionIndicatorOverlay.hxx b/sd/source/ui/slidesorter/inc/view/SlsInsertionIndicatorOverlay.hxx
new file mode 100644
index 000000000..3f4cc2218
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/view/SlsInsertionIndicatorOverlay.hxx
@@ -0,0 +1,101 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <view/SlsILayerPainter.hxx>
+#include <controller/SlsTransferableData.hxx>
+
+#include <tools/gen.hxx>
+#include <vcl/bitmapex.hxx>
+#include <memory>
+#include <vector>
+
+class OutputDevice;
+class SdTransferable;
+
+namespace sd::slidesorter { class SlideSorter; }
+
+namespace sd::slidesorter::view {
+
+class FramePainter;
+
+/** The insertion indicator is painted as a vertical or horizontal bar
+    in the space between slides.
+*/
+class InsertionIndicatorOverlay final
+    : public ILayerPainter,
+      public std::enable_shared_from_this<InsertionIndicatorOverlay>
+{
+public:
+    InsertionIndicatorOverlay (SlideSorter& rSlideSorter);
+    virtual ~InsertionIndicatorOverlay() override;
+
+    virtual void SetLayerInvalidator (const SharedILayerInvalidator& rpInvalidator) override;
+
+    void Create (const SdTransferable* pTransferable);
+
+    /** Given a position in model coordinates this method calculates the
+        insertion marker both as an index in the document and as a location
+        used for drawing the insertion indicator.
+    */
+    void SetLocation (const Point& rPosition);
+
+    Size GetSize() const;
+
+    virtual void Paint (
+        OutputDevice& rDevice,
+        const ::tools::Rectangle& rRepaintArea) override;
+
+    bool IsVisible() const { return mbIsVisible;}
+    void Hide();
+    void Show();
+
+    ::tools::Rectangle GetBoundingBox() const;
+
+private:
+    SlideSorter& mrSlideSorter;
+    bool mbIsVisible;
+    SharedILayerInvalidator mpLayerInvalidator;
+    // Center of the insertion indicator.
+    Point maLocation;
+    BitmapEx maIcon;
+    std::unique_ptr<FramePainter> mpShadowPainter;
+
+    Point PaintRepresentatives (
+        OutputDevice& rContent,
+        const Size& rPreviewSize,
+        const sal_Int32 nOffset,
+        const ::std::vector<controller::TransferableData::Representative>& rPages) const;
+    void PaintPageCount (
+        OutputDevice& rDevice,
+        const sal_Int32 nSelectionCount,
+        const Size& rPreviewSize,
+        const Point& rFirstPageOffset) const;
+    /** Setup the insertion indicator by creating the icon.  It consists of
+        scaled down previews of some of the selected pages.
+    */
+    void Create (
+        const ::std::vector<controller::TransferableData::Representative>& rPages,
+        const sal_Int32 nSelectionCount);
+};
+
+} // end of namespace ::sd::slidesorter::view
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/view/SlsLayouter.hxx b/sd/source/ui/slidesorter/inc/view/SlsLayouter.hxx
new file mode 100644
index 000000000..b91ae83c5
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/view/SlsLayouter.hxx
@@ -0,0 +1,237 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <vcl/vclptr.hxx>
+#include <tools/gen.hxx>
+#include <sal/types.h>
+#include <memory>
+
+namespace sd { class Window; }
+namespace sd::slidesorter::model { class SlideSorterModel; }
+namespace sd::slidesorter::view { class PageObjectLayouter; }
+namespace sd::slidesorter::view { class Theme; }
+
+namespace sd::slidesorter::view {
+
+class InsertPosition;
+
+/** Calculate the size and position of page objects displayed by a slide
+    sorter.  The layouter takes into account various input values:
+    1.) Size of the window in which the slide sorter is displayed.
+    2.) Desired and minimal and maximal widths of page objects.
+    3.) Minimal and maximal number of columns.
+    4.) Vertical and horizontal gaps between objects in adjacent columns.
+    5.) Borders around every page object.
+    6.) Vertical and horizontal borders between enclosing page and outer
+        page objects.
+    From these, it calculates various output values:
+    1.) The width of page objects.
+    2.) The number of columns.
+    3.) The size of the enclosing page.
+
+    <p>Sizes and lengths are all in pixel except where explicitly stated
+    otherwise.</p>
+
+    <p>The GetIndex... methods may return indices that are larger than or
+    equal to (zero based) the number of pages.  This is so because the
+    number of pages is not known to the class instances.  Indices are
+    calculated with reference to the general grid layout of page
+    objects.</p>
+*/
+class Layouter
+{
+public:
+    enum Orientation { HORIZONTAL, VERTICAL, GRID };
+
+    Layouter (
+        sd::Window *rpWindow,
+        const std::shared_ptr<Theme>& rpTheme);
+    ~Layouter();
+
+    std::shared_ptr<PageObjectLayouter> const & GetPageObjectLayouter() const;
+    /** Set the interval of valid column counts.  When nMinimalColumnCount
+        <= nMaximalColumnCount is not fulfilled then the call is ignored.
+        @param nMinimalColumnCount
+            The default value is 1.  The question whether higher values make
+            any sense is left to the caller.
+        @param nMaximalColumnCount
+            The default value is 5.
+    */
+    void SetColumnCount (sal_Int32 nMinimalColumnCount,
+        sal_Int32 nMaximalColumnCount);
+
+    /** Central method of this class.  It takes the input values and
+        calculates the output values.  Both given sizes must not be 0 in any
+        dimension or the call is ignored.
+        @param eOrientation
+            This defines the generally layout and specifies whether there may
+            be more than one row or more than one column.
+        @param rWindowSize
+            The size of the window in pixels that the slide sorter is
+            displayed in.  This can differ from the size of mpWindow during
+            detection of whether or not the scroll bars should be visible.
+        @param rPreviewModelSize
+            Size of each page in model coordinates.
+        @param rpWindow
+            The map mode of this window is adapted to the new layout of the
+            page objects.
+        @return
+            The return value indicates whether the Get... methods can be
+            used to obtain valid values (<TRUE/>).
+    */
+    bool Rearrange (
+        const Orientation eOrientation,
+        const Size& rWindowSize,
+        const Size& rPreviewModelSize,
+        const sal_uInt32 nPageCount);
+
+    /** Return the number of columns.
+    */
+    sal_Int32 GetColumnCount() const;
+
+    sal_Int32 GetIndex (const sal_Int32 nRow, const sal_Int32 nColumn) const;
+
+    Size const & GetPageObjectSize() const;
+
+    /** Return the bounding box in window coordinates of the nIndex-th page
+        object.
+    */
+    ::tools::Rectangle GetPageObjectBox (
+        const sal_Int32 nIndex,
+        const bool bIncludeBorderAndGap) const;
+
+    /** Return the bounding box in model coordinates of the page that
+        contains the given amount of page objects.
+    */
+    ::tools::Rectangle GetTotalBoundingBox() const;
+
+    /** Return the index of the first fully or partially visible page
+        object.  This takes into account only the vertical dimension.
+        @return
+            The second index may be larger than the number of existing
+            page objects.
+    */
+    Range GetRangeOfVisiblePageObjects (const ::tools::Rectangle& rVisibleArea) const;
+
+    /** Return the index of the page object that is rendered at the given
+        point.
+        @param rPosition
+            The position is expected to be in model coordinates relative to
+            the page origin.
+        @param bIncludePageBorders
+            When <TRUE/> then include the page borders into the calculation,
+            i.e. when a point lies in the border of a page object but not on
+            the actual page area the index of that page is returned;
+            otherwise -1 would be returned to indicate that no page object
+            has been hit.
+        @param bClampToValidRange
+            When <TRUE/> then values outside the valid range [0,mnPageCount)
+            are mapped to 0 (when smaller than 0) or mnPageCount-1 when
+            equal to or larger than mnPageCount.
+            When <FALSE/> then -1 is returned for values outside the valid range.
+        @return
+            The returned index may be larger than the number of existing
+            page objects.
+    */
+    sal_Int32 GetIndexAtPoint (
+        const Point& rModelPosition,
+        const bool bIncludePageBorders,
+        const bool bClampToValidRange = true) const;
+
+    /** Return an object that describes the logical and visual properties of
+        where to do an insert operation when the user would release the
+        mouse button at the given position after a drag operation and of
+        where and how to display an insertion indicator.
+        @param rModelPosition
+            The position in the model coordinate system for which to
+            determine the insertion page index.  The position does not have
+            to be over a page object to return a valid value.
+        @param rIndicatorSize
+            The size of the insertion indicator.  This size is used to adapt
+            the location when at the left or right of a row or at the top or
+            bottom of a column.
+        @param rModel
+            The model is used to get access to the selection states of the
+            pages.  This in turn is used to determine the visual bounding
+            boxes.
+    */
+    InsertPosition GetInsertPosition (
+        const Point& rModelPosition,
+        const Size& rIndicatorSize,
+        model::SlideSorterModel const & rModel) const;
+
+    Range GetValidHorizontalSizeRange() const;
+    Range GetValidVerticalSizeRange() const;
+
+    class Implementation;
+
+private:
+    std::unique_ptr<Implementation> mpImplementation;
+    VclPtr<sd::Window> mpWindow;
+};
+
+/** Collect all values concerning the logical and visual properties of the
+    insertion position that is used for drag-and-drop and copy-and-paste.
+*/
+class InsertPosition
+{
+public:
+    InsertPosition();
+    bool operator== (const InsertPosition& rInsertPosition) const;
+    bool operator!= (const InsertPosition& rInsertPosition) const;
+
+    void SetLogicalPosition (
+        const sal_Int32 nRow,
+        const sal_Int32 nColumn,
+        const sal_Int32 nIndex,
+        const bool bIsAtRunStart,
+        const bool bIsAtRunEnd,
+        const bool bIsExtraSpaceNeeded);
+    void SetGeometricalPosition(
+        const Point& rLocation,
+        const Point& rLeadingOffset,
+        const Point& rTrailingOffset);
+
+    sal_Int32 GetRow() const { return mnRow; }
+    sal_Int32 GetColumn() const { return mnColumn; }
+    sal_Int32 GetIndex() const { return mnIndex; }
+    const Point& GetLocation() const { return maLocation; }
+    const Point& GetLeadingOffset() const { return maLeadingOffset; }
+    const Point& GetTrailingOffset() const { return maTrailingOffset; }
+    bool IsAtRunStart() const { return mbIsAtRunStart; }
+    bool IsAtRunEnd() const { return mbIsAtRunEnd; }
+    bool IsExtraSpaceNeeded() const { return mbIsExtraSpaceNeeded; }
+
+private:
+    sal_Int32 mnRow;
+    sal_Int32 mnColumn;
+    sal_Int32 mnIndex;
+    bool mbIsAtRunStart : 1;
+    bool mbIsAtRunEnd : 1;
+    bool mbIsExtraSpaceNeeded : 1;
+    Point maLocation;
+    Point maLeadingOffset;
+    Point maTrailingOffset;
+};
+
+} // end of namespace ::sd::slidesorter::view
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/view/SlsPageObjectLayouter.hxx b/sd/source/ui/slidesorter/inc/view/SlsPageObjectLayouter.hxx
new file mode 100644
index 000000000..8bb77a988
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/view/SlsPageObjectLayouter.hxx
@@ -0,0 +1,144 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <model/SlsSharedPageDescriptor.hxx>
+#include <tools/gen.hxx>
+#include <vcl/image.hxx>
+
+namespace vcl { class Font; }
+namespace sd { class Window; }
+
+namespace sd::slidesorter::view {
+
+/** In contrast to the Layouter that places page objects in the view, the
+    PageObjectLayouter places the parts of individual page objects like page
+    number area, borders, preview.
+*/
+class PageObjectLayouter
+{
+public:
+    /** Create a new PageObjectLayouter object.
+        @param rPageObjectSize
+            In general either the width or the height will be 0 in order to
+            signal that this size component has to be calculated from the other.
+            This calculation will make the preview as large as possible.
+        @param nPageCount
+            The page count is used to determine how wide the page number
+            area has to be, how many digits to except for the largest page number.
+    */
+    PageObjectLayouter(
+        const Size& rPageObjectWindowSize,
+        const Size& rPreviewModelSize,
+        sd::Window *pWindow,
+        const sal_Int32 nPageCount);
+    ~PageObjectLayouter();
+
+    enum class Part {
+        // The focus indicator is painted outside the actual page object.
+        FocusIndicator,
+        // This is the outer bounding box that includes the preview, page
+        // number, title.
+        PageObject,
+        // Bounding box of the actual preview.
+        Preview,
+        // Bounding box of the page number.
+        PageNumber,
+        // Indicator whether or not there is a slide transition associated
+        // with this slide.
+        TransitionEffectIndicator,
+        // Indicator whether or not there is a custom animation associated
+        // with this slide.
+        CustomAnimationEffectIndicator
+    };
+    /** Two coordinate systems are supported.  They differ only in
+        translation not in scale.  Both relate to pixel values in the window.
+        A position in the model coordinate system does not change when the window content is
+        scrolled up or down.  In the window coordinate system (relative
+        to the top left point of the window)scrolling leads to different values.
+    */
+    enum CoordinateSystem {
+        WindowCoordinateSystem,
+        ModelCoordinateSystem
+    };
+
+    /** Return the bounding box of the page object or one of its graphical
+        parts.
+        @param rWindow
+            This device is used to translate between model and window
+            coordinates.
+        @param rpPageDescriptor
+            The page for which to calculate the bounding box.  This may be
+            NULL.  When it is NULL then a generic bounding box is calculated
+            for the location (0,0).
+        @param ePart
+            The part of the page object for which to return the bounding
+            box.
+        @param eCoordinateSystem
+            The bounding box can be returned in model and in pixel
+            (window) coordinates.
+        @param bIgnoreLocation
+            Return a position ignoring the slides' location, ie. as if
+            we were the first slide.
+    */
+    ::tools::Rectangle GetBoundingBox (
+        const model::SharedPageDescriptor& rpPageDescriptor,
+        const Part ePart,
+        const CoordinateSystem eCoordinateSystem,
+        bool bIgnoreLocation = false);
+
+    /// the size of the embedded preview: position independent, in window coordinate system
+    Size GetPreviewSize();
+
+    /// the maximum size of each tile, also position independent, in window coordinate system
+    Size GetGridMaxSize();
+
+    const Image& GetTransitionEffectIcon() const { return maTransitionEffectIcon;}
+    const Image& GetCustomAnimationEffectIcon() const { return maCustomAnimationEffectIcon;}
+
+private:
+    ::tools::Rectangle GetBoundingBox (
+        const Point& rPageObjectLocation,
+        const Part ePart,
+        const CoordinateSystem eCoordinateSystem);
+
+private:
+    VclPtr<sd::Window> mpWindow;
+    ::tools::Rectangle maFocusIndicatorBoundingBox;
+    ::tools::Rectangle maPageObjectBoundingBox;
+    ::tools::Rectangle maPageNumberAreaBoundingBox;
+    ::tools::Rectangle maPreviewBoundingBox;
+    ::tools::Rectangle maTransitionEffectBoundingBox;
+    ::tools::Rectangle maCustomAnimationEffectBoundingBox;
+    const Image maTransitionEffectIcon;
+    const Image maCustomAnimationEffectIcon;
+    const std::shared_ptr<vcl::Font> mpPageNumberFont;
+
+    Size GetPageNumberAreaSize (const int nPageCount);
+    ::tools::Rectangle CalculatePreviewBoundingBox (
+        Size& rPageObjectSize,
+        const Size& rPreviewModelSize,
+        const sal_Int32 nPageNumberAreaWidth,
+        const sal_Int32 nFocusIndicatorWidth);
+};
+
+} // end of namespace ::sd::slidesorter::view
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/view/SlsPageObjectPainter.hxx b/sd/source/ui/slidesorter/inc/view/SlsPageObjectPainter.hxx
new file mode 100644
index 000000000..747c09500
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/view/SlsPageObjectPainter.hxx
@@ -0,0 +1,119 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <model/SlsSharedPageDescriptor.hxx>
+#include <view/SlsTheme.hxx>
+#include <memory>
+
+namespace sd::slidesorter::cache { class PageCache; }
+namespace sd::slidesorter { class SlideSorter; }
+
+namespace sd::slidesorter::view {
+
+class Layouter;
+class PageObjectLayouter;
+class FramePainter;
+
+class PageObjectPainter
+{
+public:
+    PageObjectPainter (const SlideSorter& rSlideSorter);
+    ~PageObjectPainter();
+
+    void PaintPageObject (
+        OutputDevice& rDevice,
+        const model::SharedPageDescriptor& rpDescriptor);
+
+    /** Called when the theme changes, either because it is replaced with
+        another or because the system colors have changed.  So, even when
+        the given theme is the same object as the one already in use by this
+        painter everything that depends on the theme is updated.
+    */
+    void SetTheme (const std::shared_ptr<view::Theme>& rpTheme);
+
+    /** Return a preview bitmap for the given page descriptor.  When the
+        page is excluded from the show then the preview is marked
+        accordingly.
+        @rpDescriptor
+            Defines the page for which to return the preview.
+        @pReferenceDevice
+            When not <NULL/> then this reference device is used to created a
+            compatible bitmap.
+        @return
+            The returned bitmap may have a different size then the preview area.
+    */
+    BitmapEx GetPreviewBitmap (
+        const model::SharedPageDescriptor& rpDescriptor,
+        const OutputDevice* pReferenceDevice) const;
+
+private:
+    const Layouter& mrLayouter;
+    std::shared_ptr<cache::PageCache> mpCache;
+    std::shared_ptr<view::Theme> mpTheme;
+    std::shared_ptr<vcl::Font> mpPageNumberFont;
+    std::unique_ptr<FramePainter> mpShadowPainter;
+    std::unique_ptr<FramePainter> mpFocusBorderPainter;
+
+    void PaintBackground (
+        PageObjectLayouter *pPageObjectLayouter,
+        OutputDevice& rDevice,
+        const model::SharedPageDescriptor& rpDescriptor) const;
+    void PaintPreview (
+        PageObjectLayouter *pPageObjectLayouter,
+        OutputDevice& rDevice,
+        const model::SharedPageDescriptor& rpDescriptor) const;
+    void PaintPageNumber (
+        PageObjectLayouter *pPageObjectLayouter,
+        OutputDevice& rDevice,
+        const model::SharedPageDescriptor& rpDescriptor) const;
+    static void PaintTransitionEffect (
+        PageObjectLayouter *pPageObjectLayouter,
+        OutputDevice& rDevice,
+        const model::SharedPageDescriptor& rpDescriptor);
+    static void PaintCustomAnimationEffect (
+        PageObjectLayouter *pPageObjectLayouter,
+        OutputDevice& rDevice,
+        const model::SharedPageDescriptor& rpDescriptor);
+    void PaintBorder (
+        OutputDevice& rDevice,
+        const Theme::GradientColorType eColorType,
+        const ::tools::Rectangle& rBox) const;
+    void PaintBackgroundDetail(
+        PageObjectLayouter *pPageObjectLayouter,
+        OutputDevice& rDevice,
+        const model::SharedPageDescriptor& rpDescriptor) const;
+
+    static BitmapEx CreateMarkedPreview(
+        const Size& rSize,
+        const BitmapEx& rPreview,
+        const BitmapEx& rOverlay,
+        const OutputDevice* pReferenceDevice);
+
+    /** Update the local pointer to the page object layouter to the
+        one owned by the general layouter.
+        Return <TRUE/> when after the call we have a valid page object layouter.
+    */
+    bool UpdatePageObjectLayouter();
+};
+
+} // end of namespace sd::slidesorter::view
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/view/SlsTheme.hxx b/sd/source/ui/slidesorter/inc/view/SlsTheme.hxx
new file mode 100644
index 000000000..efb7b2a3e
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/view/SlsTheme.hxx
@@ -0,0 +1,135 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <vcl/bitmapex.hxx>
+#include <tools/color.hxx>
+
+#include <memory>
+
+namespace vcl { class Font; }
+
+namespace sd::slidesorter::controller { class Properties; }
+
+namespace sd::slidesorter::view {
+
+const int Theme_FocusIndicatorWidth = 3;
+
+/** Collection of colors and styles that are used to paint the slide sorter
+    view.
+*/
+class Theme
+{
+public:
+    Theme (const std::shared_ptr<controller::Properties>& rpProperties);
+
+    /** Call this method to update some colors as response to a change of
+        a system color change.
+    */
+    void Update (
+        const std::shared_ptr<controller::Properties>& rpProperties);
+
+    //    BitmapEx GetInsertIndicatorIcon() const;
+
+    enum FontType {
+        Font_PageNumber,
+        Font_PageCount
+    };
+    static std::shared_ptr<vcl::Font> GetFont (
+        const FontType eType,
+        const OutputDevice& rDevice);
+
+    enum ColorType {
+        Color_Background,
+        Color_PageNumberDefault,
+        Color_PageNumberHover,
+        Color_PageNumberHighContrast,
+        Color_PageNumberBrightBackground,
+        Color_PageNumberDarkBackground,
+        Color_Selection,
+        Color_PreviewBorder,
+        Color_PageCountFontColor,
+        ColorType_Size_
+    };
+    Color GetColor (const ColorType eType);
+
+    enum GradientColorType {
+        Gradient_NormalPage,
+        Gradient_SelectedPage,
+        Gradient_SelectedAndFocusedPage,
+        Gradient_MouseOverPage,
+        Gradient_MouseOverSelected,
+        Gradient_MouseOverSelectedAndFocusedPage,
+        Gradient_FocusedPage,
+        GradientColorType_Size_
+    };
+    enum class GradientColorClass {
+        Border1,
+        Border2,
+        Fill1,
+        Fill2
+    };
+    Color GetGradientColor (
+        const GradientColorType eType,
+        const GradientColorClass eClass);
+    void SetGradient (
+        const GradientColorType eType,
+        const Color aBaseColor,
+        const sal_Int32 nSaturationOverride,
+        const sal_Int32 nBrightnessOverride,
+        const sal_Int32 nFillStartOffset,
+        const sal_Int32 nFillEndOffset,
+        const sal_Int32 nBorderStartOffset,
+        const sal_Int32 nBorderEndOffset);
+
+    enum IconType
+    {
+        Icon_RawShadow,
+        Icon_RawInsertShadow,
+        Icon_HideSlideOverlay,
+        Icon_FocusBorder,
+        IconType_Size_
+    };
+    const BitmapEx& GetIcon (const IconType eType);
+
+private:
+    class GradientDescriptor
+    {
+    public:
+        Color maFillColor1;
+        Color maFillColor2;
+        Color maBorderColor1;
+        Color maBorderColor2;
+    };
+    Color maBackgroundColor;
+    ::std::vector<GradientDescriptor> maGradients;
+    ::std::vector<BitmapEx> maIcons;
+    ::std::vector<Color> maColor;
+
+    GradientDescriptor& GetGradient (const GradientColorType eType);
+    /** Guarded initialization of the specified icon in the maIcons
+        container.
+    */
+    void InitializeIcon(const IconType eType, const OUString& rResourceId);
+};
+
+} // end of namespace ::sd::slidesorter::view
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/inc/view/SlsToolTip.hxx b/sd/source/ui/slidesorter/inc/view/SlsToolTip.hxx
new file mode 100644
index 000000000..6c3557e64
--- /dev/null
+++ b/sd/source/ui/slidesorter/inc/view/SlsToolTip.hxx
@@ -0,0 +1,75 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <model/SlsSharedPageDescriptor.hxx>
+#include <rtl/ustring.hxx>
+#include <vcl/timer.hxx>
+
+namespace sd::slidesorter
+{
+class SlideSorter;
+}
+
+namespace sd::slidesorter::view
+{
+/** Manage the display of tool tips.  The tool tip text changes when the
+    mouse is moved from slide to slide or from button to button.
+    After the mouse enters a slide the first display of the tool tip is
+    delayed for a short time in order to not draw attention from the slide
+    or its button bar.
+*/
+class ToolTip
+{
+public:
+    ToolTip(SlideSorter& rSlideSorter);
+    ~ToolTip();
+
+    /** Set a new page.  This modifies the default help text.  After a page
+        change a timer is started to delay the display of the tool tip for
+        the new page.
+        @param rpPage
+            When this is empty then the tool tip is hidden.
+    */
+    void SetPage(const model::SharedPageDescriptor& rpPage);
+
+    /** Hide the tool tip.
+        @return
+            Returns whether the tool tip was visible at the time this method
+            was called.
+    */
+    bool Hide();
+
+private:
+    SlideSorter& mrSlideSorter;
+    model::SharedPageDescriptor mpDescriptor;
+    OUString msCurrentHelpText;
+    void* mnHelpWindowHandle;
+    Timer maShowTimer;
+    Timer maHiddenTimer;
+
+    void DoShow();
+
+    DECL_LINK(DelayTrigger, Timer*, void);
+};
+
+} // end of namespace ::sd::slidesorter::view
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/model/SlideSorterModel.cxx b/sd/source/ui/slidesorter/model/SlideSorterModel.cxx
new file mode 100644
index 000000000..4d3e79656
--- /dev/null
+++ b/sd/source/ui/slidesorter/model/SlideSorterModel.cxx
@@ -0,0 +1,676 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <model/SlideSorterModel.hxx>
+
+#include <SlideSorter.hxx>
+#include <sal/log.hxx>
+#include <model/SlsPageDescriptor.hxx>
+#include <model/SlsPageEnumerationProvider.hxx>
+#include <controller/SlideSorterController.hxx>
+#include <controller/SlsPageSelector.hxx>
+#include <controller/SlsCurrentSlideManager.hxx>
+#include <controller/SlsSlotManager.hxx>
+#include <com/sun/star/drawing/XDrawPagesSupplier.hpp>
+#include <com/sun/star/drawing/XMasterPagesSupplier.hpp>
+#include <com/sun/star/beans/XPropertySet.hpp>
+#include <com/sun/star/frame/XController.hpp>
+
+#include <vcl/uitest/logger.hxx>
+#include <vcl/uitest/eventdescription.hxx>
+
+#include <ViewShellBase.hxx>
+#include <DrawDocShell.hxx>
+#include <drawdoc.hxx>
+#include <sdpage.hxx>
+#include <FrameView.hxx>
+
+#include <o3tl/safeint.hxx>
+#include <tools/diagnose_ex.h>
+
+using namespace ::com::sun::star;
+using namespace ::com::sun::star::uno;
+
+namespace sd::slidesorter::model {
+
+namespace {
+    bool PrintModel (const SlideSorterModel& rModel)
+    {
+        for (sal_Int32 nIndex=0,nCount=rModel.GetPageCount(); nIndex<nCount; ++nIndex)
+        {
+            SharedPageDescriptor pDescriptor (rModel.GetPageDescriptor(nIndex));
+            if (pDescriptor)
+            {
+                SAL_INFO(
+                    "sd.sls",
+                    nIndex << " " << pDescriptor->GetPageIndex() << " "
+                        << pDescriptor->GetVisualState().mnPageId << " "
+                        << FromCoreIndex(pDescriptor->GetPage()->GetPageNum())
+                        << " " << pDescriptor->GetPage());
+            }
+            else
+            {
+                SAL_INFO("sd.sls", nIndex);
+            }
+        }
+
+        return true;
+    }
+    bool CheckModel (const SlideSorterModel& rModel)
+    {
+        for (sal_Int32 nIndex=0,nCount=rModel.GetPageCount(); nIndex<nCount; ++nIndex)
+        {
+            SharedPageDescriptor pDescriptor (rModel.GetPageDescriptor(nIndex));
+            if ( ! pDescriptor)
+            {
+                PrintModel(rModel);
+                assert(pDescriptor);
+                return false;
+            }
+            if (nIndex != pDescriptor->GetPageIndex())
+            {
+                PrintModel(rModel);
+                assert(nIndex == pDescriptor->GetPageIndex());
+                return false;
+            }
+            if (nIndex != pDescriptor->GetVisualState().mnPageId)
+            {
+                PrintModel(rModel);
+                assert(nIndex == pDescriptor->GetVisualState().mnPageId);
+                return false;
+            }
+        }
+
+        return true;
+    }
+}
+
+namespace {
+
+void collectUIInformation(const OUString& num, const OUString& rAction)
+{
+    EventDescription aDescription;
+    aDescription.aID = "impress_win_or_draw_win";
+    aDescription.aParameters = {{"POS", num}};
+    aDescription.aAction = rAction;
+    aDescription.aKeyWord = "ImpressWindowUIObject";
+    aDescription.aParent = "MainWindow";
+
+    UITestLogger::getInstance().logEvent(aDescription);
+}
+
+}
+
+SlideSorterModel::SlideSorterModel (SlideSorter& rSlideSorter)
+    : mrSlideSorter(rSlideSorter),
+      meEditMode(EditMode::Page),
+      maPageDescriptors(0)
+{
+}
+
+SlideSorterModel::~SlideSorterModel()
+{
+    ClearDescriptorList ();
+}
+
+void SlideSorterModel::Dispose()
+{
+    ClearDescriptorList ();
+}
+
+SdDrawDocument* SlideSorterModel::GetDocument()
+{
+    if (mrSlideSorter.GetViewShellBase() != nullptr)
+        return mrSlideSorter.GetViewShellBase()->GetDocument();
+    else
+         return nullptr;
+}
+
+bool SlideSorterModel::SetEditMode (EditMode eEditMode)
+{
+    bool bEditModeChanged = false;
+    if (meEditMode != eEditMode)
+    {
+        meEditMode = eEditMode;
+        UpdatePageList();
+        bEditModeChanged = true;
+    }
+    return bEditModeChanged;
+}
+
+sal_Int32 SlideSorterModel::GetPageCount() const
+{
+    return maPageDescriptors.size();
+}
+
+SharedPageDescriptor SlideSorterModel::GetPageDescriptor (
+    const sal_Int32 nPageIndex,
+    const bool bCreate) const
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    SharedPageDescriptor pDescriptor;
+
+    if (nPageIndex>=0 && nPageIndex<GetPageCount())
+    {
+        pDescriptor = maPageDescriptors[nPageIndex];
+        if (pDescriptor == nullptr && bCreate && mxSlides.is())
+        {
+            SdPage* pPage = GetPage(nPageIndex);
+            pDescriptor = std::make_shared<PageDescriptor>(
+                Reference<drawing::XDrawPage>(mxSlides->getByIndex(nPageIndex),UNO_QUERY),
+                pPage,
+                nPageIndex);
+            maPageDescriptors[nPageIndex] = pDescriptor;
+        }
+    }
+
+    return pDescriptor;
+}
+
+sal_Int32 SlideSorterModel::GetIndex (const Reference<drawing::XDrawPage>& rxSlide) const
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    // First try to guess the right index.
+    Reference<beans::XPropertySet> xSet (rxSlide, UNO_QUERY);
+    if (xSet.is())
+    {
+        try
+        {
+            const Any aNumber (xSet->getPropertyValue("Number"));
+            sal_Int16 nNumber (-1);
+            aNumber >>= nNumber;
+            nNumber -= 1;
+            SharedPageDescriptor pDescriptor (GetPageDescriptor(nNumber, false));
+            if (pDescriptor
+                && pDescriptor->GetXDrawPage() == rxSlide)
+            {
+                return nNumber;
+            }
+        }
+        catch (uno::Exception&)
+        {
+            DBG_UNHANDLED_EXCEPTION("sd");
+        }
+    }
+
+    // Guess was wrong, iterate over all slides and search for the right
+    // one.
+    const sal_Int32 nCount (maPageDescriptors.size());
+    for (sal_Int32 nIndex=0; nIndex<nCount; ++nIndex)
+    {
+        SharedPageDescriptor pDescriptor (maPageDescriptors[nIndex]);
+
+        // Make sure that the descriptor exists.  Without it the given slide
+        // can not be found.
+        if (!pDescriptor)
+        {
+            // Call GetPageDescriptor() to create the missing descriptor.
+            pDescriptor = GetPageDescriptor(nIndex);
+        }
+
+        if (pDescriptor->GetXDrawPage() == rxSlide)
+            return nIndex;
+    }
+
+    return  -1;
+}
+
+sal_Int32 SlideSorterModel::GetIndex (const SdrPage* pPage) const
+{
+    if (pPage == nullptr)
+        return -1;
+
+    ::osl::MutexGuard aGuard (maMutex);
+
+    // First try to guess the right index.
+    sal_Int16 nNumber ((pPage->GetPageNum()-1)/2);
+    SharedPageDescriptor pDescriptor (GetPageDescriptor(nNumber, false));
+    if (pDescriptor
+        && pDescriptor->GetPage() == pPage)
+    {
+        return nNumber;
+    }
+
+    // Guess was wrong, iterate over all slides and search for the right
+    // one.
+    const sal_Int32 nCount (maPageDescriptors.size());
+    for (sal_Int32 nIndex=0; nIndex<nCount; ++nIndex)
+    {
+        pDescriptor = maPageDescriptors[nIndex];
+
+        // Make sure that the descriptor exists.  Without it the given slide
+        // can not be found.
+        if (!pDescriptor)
+        {
+            // Call GetPageDescriptor() to create the missing descriptor.
+            pDescriptor = GetPageDescriptor(nIndex);
+        }
+
+        if (pDescriptor->GetPage() == pPage)
+            return nIndex;
+    }
+
+    return  -1;
+}
+
+sal_uInt16 SlideSorterModel::GetCoreIndex (const sal_Int32 nIndex) const
+{
+    SharedPageDescriptor pDescriptor (GetPageDescriptor(nIndex));
+    if (pDescriptor)
+        return pDescriptor->GetPage()->GetPageNum();
+    else
+        return mxSlides->getCount()*2+1;
+}
+
+/** For now this method uses a trivial algorithm: throw away all descriptors
+    and create them anew (on demand).  The main problem that we are facing
+    when designing a better algorithm is that we can not compare pointers to
+    pages stored in the PageDescriptor objects and those obtained from the
+    document: pages may have been deleted and others may have been created
+    at the exact same memory locations.
+*/
+void SlideSorterModel::Resync()
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    // Check if document and this model really differ.
+    bool bIsUpToDate (true);
+    SdDrawDocument* pDocument = GetDocument();
+    if (pDocument!=nullptr && maPageDescriptors.size()==pDocument->GetSdPageCount(PageKind::Standard))
+    {
+        for (sal_Int32 nIndex=0,nCount=maPageDescriptors.size(); nIndex<nCount; ++nIndex)
+        {
+            if (maPageDescriptors[nIndex]
+                && maPageDescriptors[nIndex]->GetPage()
+                != GetPage(nIndex))
+            {
+                SAL_INFO("sd.sls", "page " << nIndex << " differs");
+                bIsUpToDate = false;
+                break;
+            }
+        }
+    }
+    else
+    {
+        bIsUpToDate = false;
+    }
+
+    if ( ! bIsUpToDate)
+    {
+        SynchronizeDocumentSelection(); // Try to make the current selection persistent.
+        ClearDescriptorList ();
+        AdaptSize();
+        SynchronizeModelSelection();
+        mrSlideSorter.GetController().GetPageSelector().CountSelectedPages();
+    }
+    CheckModel(*this);
+}
+
+void SlideSorterModel::ClearDescriptorList()
+{
+    ::std::vector<SharedPageDescriptor> aDescriptors;
+
+    {
+        ::osl::MutexGuard aGuard (maMutex);
+        aDescriptors.swap(maPageDescriptors);
+    }
+
+    for (auto& rxDescriptor : aDescriptors)
+    {
+        if (rxDescriptor != nullptr)
+        {
+            if (rxDescriptor.use_count() > 1)
+            {
+                SAL_INFO(
+                    "sd.sls",
+                    "trying to delete page descriptor that is still used with"
+                        " count " << rxDescriptor.use_count());
+                // No assertion here because that can hang the office when
+                // opening a dialog from here.
+            }
+            rxDescriptor.reset();
+        }
+    }
+}
+
+void SlideSorterModel::SynchronizeDocumentSelection()
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    PageEnumeration aAllPages (PageEnumerationProvider::CreateAllPagesEnumeration(*this));
+    while (aAllPages.HasMoreElements())
+    {
+        SharedPageDescriptor pDescriptor (aAllPages.GetNextElement());
+        const bool bIsSelected (pDescriptor->HasState(PageDescriptor::ST_Selected));
+        pDescriptor->GetPage()->SetSelected(bIsSelected);
+    }
+}
+
+void SlideSorterModel::SynchronizeModelSelection()
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    PageEnumeration aAllPages (PageEnumerationProvider::CreateAllPagesEnumeration(*this));
+    while (aAllPages.HasMoreElements())
+    {
+        SharedPageDescriptor pDescriptor (aAllPages.GetNextElement());
+        const bool bIsSelected (pDescriptor->GetPage()->IsSelected());
+        pDescriptor->SetState(PageDescriptor::ST_Selected, bIsSelected);
+    }
+}
+
+void SlideSorterModel::SetDocumentSlides (
+    const Reference<container::XIndexAccess>& rxSlides)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    // Make the current selection persistent and then release the
+    // current set of pages.
+    SynchronizeDocumentSelection();
+    mxSlides = nullptr;
+    ClearDescriptorList ();
+
+    // Reset the current page to cause everybody to release references to it.
+    mrSlideSorter.GetController().GetCurrentSlideManager()->NotifyCurrentSlideChange(-1);
+
+    // Set the new set of pages.
+    mxSlides = rxSlides;
+    AdaptSize();
+    SynchronizeModelSelection();
+    mrSlideSorter.GetController().GetPageSelector().CountSelectedPages();
+
+    model::PageEnumeration aSelectedPages (
+        model::PageEnumerationProvider::CreateSelectedPagesEnumeration(*this));
+    if (aSelectedPages.HasMoreElements())
+    {
+        SharedPageDescriptor pDescriptor (aSelectedPages.GetNextElement());
+        mrSlideSorter.GetController().GetCurrentSlideManager()->NotifyCurrentSlideChange(
+            pDescriptor->GetPage());
+    }
+
+    ViewShell* pViewShell = mrSlideSorter.GetViewShell();
+    if (pViewShell != nullptr)
+    {
+        SdPage* pPage = pViewShell->getCurrentPage();
+        if (pPage != nullptr)
+            mrSlideSorter.GetController().GetCurrentSlideManager()->NotifyCurrentSlideChange(
+                pPage);
+        else
+        {
+            // No current page.  This can only be when the slide sorter is
+            // the main view shell.  Get current slide form frame view.
+            const FrameView* pFrameView = pViewShell->GetFrameView();
+            if (pFrameView != nullptr)
+                mrSlideSorter.GetController().GetCurrentSlideManager()->NotifyCurrentSlideChange(
+                    pFrameView->GetSelectedPage());
+            else
+            {
+                // No frame view.  As a last resort use the first slide as
+                // current slide.
+                mrSlideSorter.GetController().GetCurrentSlideManager()->NotifyCurrentSlideChange(
+                    sal_Int32(0));
+            }
+        }
+    }
+
+    mrSlideSorter.GetController().GetSlotManager()->NotifyEditModeChange();
+}
+
+Reference<container::XIndexAccess> SlideSorterModel::GetDocumentSlides() const
+{
+    ::osl::MutexGuard aGuard (maMutex);
+    return mxSlides;
+}
+
+void SlideSorterModel::UpdatePageList()
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    Reference<container::XIndexAccess> xPages;
+
+    // Get the list of pages according to the edit mode.
+    Reference<frame::XController> xController (mrSlideSorter.GetXController());
+    if (xController.is())
+    {
+        switch (meEditMode)
+        {
+            case EditMode::MasterPage:
+            {
+                Reference<drawing::XMasterPagesSupplier> xSupplier (
+                    xController->getModel(), UNO_QUERY);
+                if (xSupplier.is())
+                {
+                    xPages = xSupplier->getMasterPages();
+                }
+            }
+            break;
+
+            case EditMode::Page:
+            {
+                Reference<drawing::XDrawPagesSupplier> xSupplier (
+                    xController->getModel(), UNO_QUERY);
+                if (xSupplier.is())
+                {
+                    xPages = xSupplier->getDrawPages();
+                }
+            }
+            break;
+
+            default:
+                // We should never get here.
+                assert(false);
+                break;
+        }
+    }
+
+    mrSlideSorter.GetController().SetDocumentSlides(xPages);
+}
+
+void SlideSorterModel::AdaptSize()
+{
+    if (mxSlides.is())
+        maPageDescriptors.resize(mxSlides->getCount());
+    else
+        maPageDescriptors.resize(0);
+}
+
+bool SlideSorterModel::IsReadOnly() const
+{
+    if (mrSlideSorter.GetViewShellBase() != nullptr
+        && mrSlideSorter.GetViewShellBase()->GetDocShell())
+        return mrSlideSorter.GetViewShellBase()->GetDocShell()->IsReadOnly();
+    else
+        return true;
+}
+
+void SlideSorterModel::SaveCurrentSelection()
+{
+    PageEnumeration aPages (PageEnumerationProvider::CreateAllPagesEnumeration(*this));
+    while (aPages.HasMoreElements())
+    {
+        SharedPageDescriptor pDescriptor (aPages.GetNextElement());
+        pDescriptor->SetState(
+            PageDescriptor::ST_WasSelected,
+            pDescriptor->HasState(PageDescriptor::ST_Selected));
+    }
+}
+
+vcl::Region SlideSorterModel::RestoreSelection()
+{
+    vcl::Region aRepaintRegion;
+    PageEnumeration aPages (PageEnumerationProvider::CreateAllPagesEnumeration(*this));
+    while (aPages.HasMoreElements())
+    {
+        SharedPageDescriptor pDescriptor (aPages.GetNextElement());
+        if (pDescriptor->SetState(
+            PageDescriptor::ST_Selected,
+            pDescriptor->HasState(PageDescriptor::ST_WasSelected)))
+        {
+            aRepaintRegion.Union(pDescriptor->GetBoundingBox());
+        }
+    }
+    return aRepaintRegion;
+}
+
+bool SlideSorterModel::NotifyPageEvent (const SdrPage* pSdrPage)
+{
+    ::osl::MutexGuard aGuard (maMutex);
+
+    SdPage* pPage = const_cast<SdPage*>(dynamic_cast<const SdPage*>(pSdrPage));
+    if (pPage == nullptr)
+        return false;
+
+    // We are only interested in pages that are currently served by this
+    // model.
+    if (pPage->GetPageKind() != PageKind::Standard)
+        return false;
+    if (pPage->IsMasterPage() != (meEditMode==EditMode::MasterPage))
+        return false;
+
+    //NotifyPageEvent is called for add, remove, *and* change position so for
+    //the change position case we must ensure we don't end up with the slide
+    //duplicated in our list
+    bool bSelected = DeleteSlide(pPage);
+    if (pPage->IsInserted())
+    {
+        InsertSlide(pPage, bSelected);
+    }
+    CheckModel(*this);
+
+    return true;
+}
+
+void SlideSorterModel::InsertSlide(SdPage* pPage, bool bMarkSelected)
+{
+    // Find the index at which to insert the given page.
+    sal_uInt16 nCoreIndex (pPage->GetPageNum());
+    sal_Int32 nIndex (FromCoreIndex(nCoreIndex));
+    if (pPage != GetPage(nIndex))
+        return;
+
+    // Check that the pages in the document before and after the given page
+    // are present in this model.
+    if (nIndex>0)
+        if (GetPage(nIndex-1) != GetPageDescriptor(nIndex-1)->GetPage())
+            return;
+    if (nIndex < static_cast<sal_Int32>(maPageDescriptors.size()) -1)
+        if (GetPage(nIndex+1) != GetPageDescriptor(nIndex)->GetPage())
+            return;
+
+    auto iter = maPageDescriptors.begin() + nIndex;
+
+    // Insert the given page at index nIndex
+    iter = maPageDescriptors.insert(
+        iter,
+        std::make_shared<PageDescriptor>(
+                Reference<drawing::XDrawPage>(mxSlides->getByIndex(nIndex),UNO_QUERY),
+                pPage,
+                nIndex));
+
+    if (bMarkSelected)
+        (*iter)->SetState(PageDescriptor::ST_Selected, true);
+
+    // Update page indices.
+    UpdateIndices(nIndex+1);
+}
+
+bool SlideSorterModel::DeleteSlide (const SdPage* pPage)
+{
+    sal_Int32 nIndex(0);
+
+    // Caution, GetIndex() may be negative since it uses GetPageNumber()-1
+    // for calculation, so do this only when page is inserted, else the
+    // GetPageNumber() will be zero and thus GetIndex() == -1
+    if(pPage->IsInserted())
+    {
+        nIndex = GetIndex(pPage);
+    }
+    else
+    {
+        // if not inserted, search for page
+        for(; nIndex < static_cast<sal_Int32>(maPageDescriptors.size()); nIndex++)
+        {
+            if(maPageDescriptors[nIndex]->GetPage() == pPage)
+            {
+                break;
+            }
+        }
+    }
+
+    bool bMarkedSelected(false);
+
+    if(nIndex >= 0 && o3tl::make_unsigned(nIndex) < maPageDescriptors.size())
+    {
+        if (maPageDescriptors[nIndex])
+            if (maPageDescriptors[nIndex]->GetPage() != pPage)
+                return false;
+
+        auto iter = maPageDescriptors.begin() + nIndex;
+        bMarkedSelected = (*iter)->HasState(PageDescriptor::ST_Selected);
+        maPageDescriptors.erase(iter);
+        UpdateIndices(nIndex);
+
+        collectUIInformation(OUString::number(nIndex + 1), "Delete_Slide_or_Page");
+    }
+    return bMarkedSelected;
+}
+
+void SlideSorterModel::UpdateIndices (const sal_Int32 nFirstIndex)
+{
+    for (sal_Int32 nDescriptorIndex=0,nCount=maPageDescriptors.size();
+         nDescriptorIndex<nCount;
+         ++nDescriptorIndex)
+    {
+        SharedPageDescriptor& rpDescriptor (maPageDescriptors[nDescriptorIndex]);
+        if (rpDescriptor)
+        {
+            if (nDescriptorIndex < nFirstIndex)
+            {
+                if (rpDescriptor->GetPageIndex()!=nDescriptorIndex)
+                {
+                    assert(rpDescriptor->GetPageIndex()==nDescriptorIndex);
+                }
+            }
+            else
+            {
+                rpDescriptor->SetPageIndex(nDescriptorIndex);
+            }
+        }
+    }
+}
+
+SdPage* SlideSorterModel::GetPage (const sal_Int32 nSdIndex) const
+{
+    SdDrawDocument* pModel = const_cast<SlideSorterModel*>(this)->GetDocument();
+    if (pModel != nullptr)
+    {
+        if (meEditMode == EditMode::Page)
+            return pModel->GetSdPage (static_cast<sal_uInt16>(nSdIndex), PageKind::Standard);
+        else
+            return pModel->GetMasterSdPage (static_cast<sal_uInt16>(nSdIndex), PageKind::Standard);
+    }
+    else
+        return nullptr;
+}
+
+} // end of namespace ::sd::slidesorter::model
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/model/SlsPageDescriptor.cxx b/sd/source/ui/slidesorter/model/SlsPageDescriptor.cxx
new file mode 100644
index 000000000..5118cf58e
--- /dev/null
+++ b/sd/source/ui/slidesorter/model/SlsPageDescriptor.cxx
@@ -0,0 +1,226 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <model/SlsPageDescriptor.hxx>
+
+#include <sdpage.hxx>
+
+using namespace ::com::sun::star::uno;
+using namespace ::com::sun::star;
+
+namespace sd::slidesorter::model {
+
+PageDescriptor::PageDescriptor (
+    const Reference<drawing::XDrawPage>& rxPage,
+    SdPage* pPage,
+    const sal_Int32 nIndex)
+    : mpPage(pPage),
+      mxPage(rxPage),
+      mpMasterPage(nullptr),
+      mnIndex(nIndex),
+      maVisualState(nIndex),
+      mbIsSelected(false),
+      mbWasSelected(false),
+      mbIsVisible(false),
+      mbIsFocused(false),
+      mbIsCurrent(false),
+      mbIsMouseOver(false),
+      mbHasTransition(false)
+{
+    assert(mpPage);
+    assert(mpPage == SdPage::getImplementation(rxPage));
+    if (mpPage != nullptr)
+    {
+        if (mpPage->TRG_HasMasterPage())
+            mpMasterPage = &mpPage->TRG_GetMasterPage();
+        if (mpPage->getTransitionType() > 0)
+            mbHasTransition = true;
+    }
+}
+
+PageDescriptor::~PageDescriptor()
+{
+}
+
+void PageDescriptor::SetPageIndex (const sal_Int32 nNewIndex)
+{
+    mnIndex = nNewIndex;
+    maVisualState.mnPageId = nNewIndex;
+}
+
+bool PageDescriptor::UpdateMasterPage()
+{
+    const SdrPage* pMaster = nullptr;
+    if (mpPage!=nullptr && mpPage->TRG_HasMasterPage())
+        pMaster = &mpPage->TRG_GetMasterPage();
+    if (mpMasterPage != pMaster)
+    {
+        mpMasterPage = pMaster;
+        return true;
+    }
+    else
+        return false;
+}
+
+bool PageDescriptor::UpdateTransitionFlag()
+{
+    bool bHasSlideTransition (false);
+    if (mpPage != nullptr)
+        bHasSlideTransition = mpPage->getTransitionType() > 0;
+    if (bHasSlideTransition != mbHasTransition)
+    {
+        mbHasTransition = bHasSlideTransition;
+        return true;
+    }
+    else
+        return false;
+}
+
+bool PageDescriptor::HasState (const State eState) const
+{
+    switch (eState)
+    {
+        case ST_Visible:
+            return mbIsVisible;
+
+        case ST_Selected:
+            return mbIsSelected;
+
+        case ST_WasSelected:
+            return mbWasSelected;
+
+        case ST_Focused:
+            return mbIsFocused;
+
+        case ST_MouseOver:
+            return mbIsMouseOver;
+
+        case ST_Current:
+            return mbIsCurrent;
+
+        case ST_Excluded:
+            return mpPage!=nullptr && mpPage->IsExcluded();
+
+        default:
+            assert(false);
+            return false;
+    }
+}
+
+bool PageDescriptor::SetState (const State eState, const bool bNewStateValue)
+{
+    bool bModified (false);
+    switch (eState)
+    {
+        case ST_Visible:
+            bModified = (bNewStateValue!=mbIsVisible);
+            if (bModified)
+                mbIsVisible = bNewStateValue;
+            break;
+
+        case ST_Selected:
+            bModified = (bNewStateValue!=mbIsSelected);
+            if (bModified)
+                mbIsSelected = bNewStateValue;
+            break;
+
+        case ST_WasSelected:
+            bModified = (bNewStateValue!=mbWasSelected);
+            if (bModified)
+                mbWasSelected = bNewStateValue;
+            break;
+
+        case ST_Focused:
+            bModified = (bNewStateValue!=mbIsFocused);
+            if (bModified)
+                mbIsFocused = bNewStateValue;
+            break;
+
+        case ST_MouseOver:
+            bModified = (bNewStateValue!=mbIsMouseOver);
+            if (bModified)
+                mbIsMouseOver = bNewStateValue;
+            break;
+
+        case ST_Current:
+            bModified = (bNewStateValue!=mbIsCurrent);
+            if (bModified)
+                mbIsCurrent = bNewStateValue;
+            break;
+
+        case ST_Excluded:
+            // This is a state of the page and has to be handled differently
+            // from the view-only states.
+            if (mpPage != nullptr)
+                if (bNewStateValue != mpPage->IsExcluded())
+                {
+                    mpPage->SetExcluded(bNewStateValue);
+                    bModified = true;
+                }
+            break;
+    }
+
+    return bModified;
+}
+
+bool PageDescriptor::GetCoreSelection()
+{
+    if (mpPage!=nullptr && mpPage->IsSelected() != mbIsSelected)
+        return SetState(ST_Selected, !mbIsSelected);
+    else
+        return false;
+}
+
+void PageDescriptor::SetCoreSelection()
+{
+    if (mpPage != nullptr)
+        if (HasState(ST_Selected))
+            mpPage->SetSelected(true);
+        else
+            mpPage->SetSelected(false);
+    else
+    {
+        assert(mpPage!=nullptr);
+    }
+}
+
+::tools::Rectangle PageDescriptor::GetBoundingBox() const
+{
+    ::tools::Rectangle aBox (maBoundingBox);
+    const Point aOffset (maVisualState.GetLocationOffset());
+    aBox.Move(aOffset.X(), aOffset.Y());
+    return aBox;
+}
+
+Point PageDescriptor::GetLocation (const bool bIgnoreOffset) const
+{
+    if (bIgnoreOffset)
+        return maBoundingBox.TopLeft();
+    else
+        return maBoundingBox.TopLeft() + maVisualState.GetLocationOffset();
+}
+
+void PageDescriptor::SetBoundingBox (const ::tools::Rectangle& rBoundingBox)
+{
+    maBoundingBox = rBoundingBox;
+}
+
+} // end of namespace ::sd::slidesorter::model
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/model/SlsPageEnumeration.cxx b/sd/source/ui/slidesorter/model/SlsPageEnumeration.cxx
new file mode 100644
index 000000000..a67f057e7
--- /dev/null
+++ b/sd/source/ui/slidesorter/model/SlsPageEnumeration.cxx
@@ -0,0 +1,202 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <memory>
+#include <sal/config.h>
+
+#include <utility>
+
+#include <model/SlsPageEnumeration.hxx>
+#include <model/SlideSorterModel.hxx>
+
+using namespace ::sd::slidesorter;
+using namespace ::sd::slidesorter::model;
+
+namespace {
+
+class PageEnumerationImpl
+    : public Enumeration<SharedPageDescriptor>
+{
+public:
+    PageEnumerationImpl (
+        const SlideSorterModel& rModel,
+        const PageEnumeration::PagePredicate& rPredicate);
+    PageEnumerationImpl(const PageEnumerationImpl&) = delete;
+    PageEnumerationImpl& operator=(const PageEnumerationImpl&) = delete;
+    /** Create a copy of the called enumeration object.
+    */
+    virtual ::std::unique_ptr<Enumeration<SharedPageDescriptor> > Clone() override;
+
+    virtual bool HasMoreElements() const override;
+    virtual SharedPageDescriptor GetNextElement() override;
+    virtual void Rewind() override;
+
+private:
+    const SlideSorterModel& mrModel;
+    const PageEnumeration::PagePredicate maPredicate;
+    int mnIndex;
+
+    /** This constructor sets the internal page index to the given value.
+        It does not call AdvanceToNextValidElement() to skip elements that
+        do not fulfill Predicate.
+    */
+    PageEnumerationImpl (
+        const SlideSorterModel& rModel,
+        const PageEnumeration::PagePredicate& rPredicate,
+        int nIndex);
+
+    /** Skip all elements that do not fulfill Predicate starting with the
+        one pointed to by mnIndex.
+    */
+    void AdvanceToNextValidElement();
+};
+
+} // end of anonymous namespace
+
+namespace sd::slidesorter::model {
+
+PageEnumeration PageEnumeration::Create (
+    const SlideSorterModel& rModel,
+    const PagePredicate& rPredicate)
+{
+    return PageEnumeration(::std::unique_ptr<Enumeration<SharedPageDescriptor> >(
+        new PageEnumerationImpl(rModel, rPredicate)));
+}
+
+PageEnumeration::PageEnumeration (
+    ::std::unique_ptr<Enumeration<SharedPageDescriptor> > && pImpl)
+    : mpImpl(std::move(pImpl))
+{
+}
+
+PageEnumeration::PageEnumeration (const PageEnumeration& rEnumeration )
+: sd::slidesorter::model::Enumeration<sd::slidesorter::model::SharedPageDescriptor>()
+{
+    mpImpl = rEnumeration.mpImpl->Clone();
+}
+
+PageEnumeration::~PageEnumeration()
+{
+}
+
+PageEnumeration& PageEnumeration::operator= (
+    const PageEnumeration& rEnumeration)
+{
+    mpImpl = rEnumeration.mpImpl->Clone();
+    return *this;
+}
+
+::std::unique_ptr<Enumeration<SharedPageDescriptor> > PageEnumeration::Clone()
+{
+    return ::std::unique_ptr<Enumeration<SharedPageDescriptor> >(
+        new PageEnumeration (*this));
+}
+
+bool PageEnumeration::HasMoreElements() const
+{
+    return mpImpl->HasMoreElements();
+}
+
+SharedPageDescriptor PageEnumeration::GetNextElement()
+{
+    return mpImpl->GetNextElement();
+}
+
+void PageEnumeration::Rewind()
+{
+    return mpImpl->Rewind();
+}
+
+} // end of namespace ::sd::slidesorter::model
+
+namespace {
+
+PageEnumerationImpl::PageEnumerationImpl (
+    const SlideSorterModel& rModel,
+    const PageEnumeration::PagePredicate& rPredicate)
+    : mrModel(rModel),
+      maPredicate(rPredicate),
+      mnIndex(0)
+{
+    Rewind();
+}
+
+PageEnumerationImpl::PageEnumerationImpl (
+    const SlideSorterModel& rModel,
+    const PageEnumeration::PagePredicate& rPredicate,
+    int nIndex)
+    : mrModel(rModel),
+      maPredicate(rPredicate),
+      mnIndex(nIndex)
+{
+}
+
+::std::unique_ptr<Enumeration<SharedPageDescriptor> >
+    PageEnumerationImpl::Clone()
+{
+    return ::std::unique_ptr<Enumeration<SharedPageDescriptor> >(
+        new PageEnumerationImpl(mrModel,maPredicate,mnIndex));
+}
+
+bool PageEnumerationImpl::HasMoreElements() const
+{
+    return (mnIndex < mrModel.GetPageCount());
+}
+
+SharedPageDescriptor PageEnumerationImpl::GetNextElement()
+{
+    SharedPageDescriptor pDescriptor (mrModel.GetPageDescriptor(mnIndex));
+
+    // Go to the following valid element.
+    mnIndex += 1;
+    AdvanceToNextValidElement();
+
+    return pDescriptor;
+}
+
+void PageEnumerationImpl::Rewind()
+{
+    // Go to first valid element.
+    mnIndex = 0;
+    AdvanceToNextValidElement();
+}
+
+void PageEnumerationImpl::AdvanceToNextValidElement()
+{
+    while (mnIndex < mrModel.GetPageCount())
+    {
+        SharedPageDescriptor pDescriptor (mrModel.GetPageDescriptor(mnIndex));
+
+        // Test for the predicate being fulfilled.
+        if (pDescriptor && maPredicate(pDescriptor))
+        {
+            // This predicate is valid.
+            break;
+        }
+        else
+        {
+            // Advance to next predicate.
+            mnIndex += 1;
+        }
+    }
+}
+
+} // end of anonymous namespace
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/model/SlsPageEnumerationProvider.cxx b/sd/source/ui/slidesorter/model/SlsPageEnumerationProvider.cxx
new file mode 100644
index 000000000..800fa12db
--- /dev/null
+++ b/sd/source/ui/slidesorter/model/SlsPageEnumerationProvider.cxx
@@ -0,0 +1,81 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <model/SlsPageEnumerationProvider.hxx>
+#include <model/SlsPageEnumeration.hxx>
+#include <model/SlsPageDescriptor.hxx>
+
+namespace sd::slidesorter::model {
+
+namespace {
+
+class AllPagesPredicate
+{
+public:
+    bool operator() (const SharedPageDescriptor&) const
+    {
+        return true;
+    }
+};
+
+class SelectedPagesPredicate
+{
+public:
+    bool operator() (const SharedPageDescriptor& rpDescriptor)
+    {
+        return rpDescriptor->HasState(PageDescriptor::ST_Selected);
+    }
+};
+
+class VisiblePagesPredicate
+{
+public:
+    bool operator() (const SharedPageDescriptor& rpDescriptor)
+    {
+        return rpDescriptor->HasState(PageDescriptor::ST_Visible);
+    }
+};
+
+}
+
+PageEnumeration PageEnumerationProvider::CreateAllPagesEnumeration (
+    const SlideSorterModel& rModel)
+{
+    return PageEnumeration::Create(rModel, AllPagesPredicate());
+}
+
+PageEnumeration PageEnumerationProvider::CreateSelectedPagesEnumeration (
+    const SlideSorterModel& rModel)
+{
+    return PageEnumeration::Create(
+        rModel,
+        SelectedPagesPredicate());
+}
+
+PageEnumeration PageEnumerationProvider::CreateVisiblePagesEnumeration (
+    const SlideSorterModel& rModel)
+{
+    return PageEnumeration::Create(
+        rModel,
+        VisiblePagesPredicate());
+}
+
+} // end of namespace ::sd::slidesorter::model
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/model/SlsVisualState.cxx b/sd/source/ui/slidesorter/model/SlsVisualState.cxx
new file mode 100644
index 000000000..3e16823ff
--- /dev/null
+++ b/sd/source/ui/slidesorter/model/SlsVisualState.cxx
@@ -0,0 +1,40 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <model/SlsVisualState.hxx>
+
+namespace sd::slidesorter::model
+{
+VisualState::VisualState(const sal_Int32 nPageId)
+    : mnPageId(nPageId)
+    , maLocationOffset(0, 0)
+{
+}
+
+void VisualState::SetLocationOffset(const Point& rOffset)
+{
+    if (maLocationOffset != rOffset)
+    {
+        maLocationOffset = rOffset;
+    }
+}
+
+} // end of namespace ::sd::slidesorter::model
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/shell/SlideSorter.cxx b/sd/source/ui/slidesorter/shell/SlideSorter.cxx
new file mode 100644
index 000000000..550a40469
--- /dev/null
+++ b/sd/source/ui/slidesorter/shell/SlideSorter.cxx
@@ -0,0 +1,456 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <SlideSorter.hxx>
+
+#include <com/sun/star/frame/XController.hpp>
+
+#include <controller/SlideSorterController.hxx>
+#include <controller/SlsScrollBarManager.hxx>
+#include <controller/SlsProperties.hxx>
+#include <controller/SlsAnimator.hxx>
+#include <o3tl/deleter.hxx>
+#include <view/SlideSorterView.hxx>
+#include <view/SlsTheme.hxx>
+#include <model/SlideSorterModel.hxx>
+
+#include <ViewShell.hxx>
+#include <ViewShellBase.hxx>
+#include <Window.hxx>
+
+#include <tools/debug.hxx>
+#include <vcl/scrbar.hxx>
+#include <vcl/svapp.hxx>
+#include <vcl/settings.hxx>
+
+using namespace ::com::sun::star::uno;
+using namespace ::com::sun::star;
+
+namespace sd::slidesorter {
+
+namespace {
+class ContentWindow : public ::sd::Window
+{
+public:
+    ContentWindow(vcl::Window& rParent, SlideSorter& rSlideSorter);
+
+    void SetCurrentFunction (const rtl::Reference<FuPoor>& rpFunction);
+    virtual void Paint(vcl::RenderContext& /*rRenderContext*/, const ::tools::Rectangle& rRect) override;
+    virtual void KeyInput (const KeyEvent& rEvent) override;
+    virtual void MouseMove (const MouseEvent& rEvent) override;
+    virtual void MouseButtonUp (const MouseEvent& rEvent) override;
+    virtual void MouseButtonDown (const MouseEvent& rEvent) override;
+    virtual void Command (const CommandEvent& rEvent) override;
+    virtual bool EventNotify (NotifyEvent& rEvent) override;
+
+private:
+    SlideSorter& mrSlideSorter;
+    rtl::Reference<FuPoor> mpCurrentFunction;
+};
+}
+
+//===== SlideSorter ===========================================================
+
+std::shared_ptr<SlideSorter> SlideSorter::CreateSlideSorter(
+    ViewShell& rViewShell,
+    sd::Window* pContentWindow,
+    ScrollBar* pHorizontalScrollBar,
+    ScrollBar* pVerticalScrollBar,
+    ScrollBarBox* pScrollBarBox)
+{
+    std::shared_ptr<SlideSorter> pSlideSorter(
+        new SlideSorter(
+            rViewShell,
+            pContentWindow,
+            pHorizontalScrollBar,
+            pVerticalScrollBar,
+            pScrollBarBox),
+        o3tl::default_delete<SlideSorter>());
+    pSlideSorter->Init();
+    return pSlideSorter;
+}
+
+std::shared_ptr<SlideSorter> SlideSorter::CreateSlideSorter (
+    ViewShellBase& rBase,
+    vcl::Window& rParentWindow)
+{
+    std::shared_ptr<SlideSorter> pSlideSorter(
+        new SlideSorter(
+            rBase,
+            rParentWindow),
+        o3tl::default_delete<SlideSorter>());
+    pSlideSorter->Init();
+    return pSlideSorter;
+}
+
+SlideSorter::SlideSorter (
+    ViewShell& rViewShell,
+    sd::Window* pContentWindow,
+    ScrollBar* pHorizontalScrollBar,
+    ScrollBar* pVerticalScrollBar,
+    ScrollBarBox* pScrollBarBox)
+    : mbIsValid(false),
+      mpViewShell(&rViewShell),
+      mpViewShellBase(&rViewShell.GetViewShellBase()),
+      mpContentWindow(pContentWindow),
+      mpHorizontalScrollBar(pHorizontalScrollBar),
+      mpVerticalScrollBar(pVerticalScrollBar),
+      mpScrollBarBox(pScrollBarBox),
+      mpProperties(std::make_shared<controller::Properties>()),
+      mpTheme(std::make_shared<view::Theme>(mpProperties))
+{
+}
+
+SlideSorter::SlideSorter (
+    ViewShellBase& rBase,
+    vcl::Window& rParentWindow)
+    : mbIsValid(false),
+      mpViewShell(nullptr),
+      mpViewShellBase(&rBase),
+      mpContentWindow(VclPtr<ContentWindow>::Create(rParentWindow,*this )),
+      mpHorizontalScrollBar(VclPtr<ScrollBar>::Create(&rParentWindow,WinBits(WB_HSCROLL | WB_DRAG))),
+      mpVerticalScrollBar(VclPtr<ScrollBar>::Create(&rParentWindow,WinBits(WB_VSCROLL | WB_DRAG))),
+      mpScrollBarBox(VclPtr<ScrollBarBox>::Create(&rParentWindow)),
+      mpProperties(std::make_shared<controller::Properties>()),
+      mpTheme(std::make_shared<view::Theme>(mpProperties))
+{
+}
+
+void SlideSorter::Init()
+{
+    if (mpViewShellBase != nullptr)
+        mxControllerWeak = mpViewShellBase->GetController();
+
+    // Reinitialize colors in Properties with window specific values.
+    if (mpContentWindow)
+    {
+        mpProperties->SetBackgroundColor(
+            mpContentWindow->GetSettings().GetStyleSettings().GetWindowColor());
+        mpProperties->SetTextColor(
+            mpContentWindow->GetSettings().GetStyleSettings().GetWindowTextColor());
+        mpProperties->SetSelectionColor(
+            mpContentWindow->GetSettings().GetStyleSettings().GetMenuHighlightColor());
+        mpProperties->SetHighlightColor(
+            mpContentWindow->GetSettings().GetStyleSettings().GetMenuHighlightColor());
+    }
+
+    CreateModelViewController ();
+
+    SetupListeners ();
+
+    // Initialize the window.
+    sd::Window *pContentWindow = GetContentWindow().get();
+    if (!pContentWindow)
+        return;
+
+    vcl::Window* pParentWindow = pContentWindow->GetParent();
+    if (pParentWindow != nullptr)
+        pParentWindow->SetBackground(Wallpaper());
+    pContentWindow->SetBackground(Wallpaper());
+    pContentWindow->SetViewOrigin (Point(0,0));
+    // We do our own scrolling while dragging a page selection.
+    pContentWindow->SetUseDropScroll (false);
+    // Change the winbits so that the active window accepts the focus.
+    pContentWindow->SetStyle ((pContentWindow->GetStyle() & ~WB_DIALOGCONTROL) | WB_TABSTOP);
+    pContentWindow->Hide();
+
+    // Set view pointer of base class.
+    SetupControls();
+
+    mbIsValid = true;
+}
+
+SlideSorter::~SlideSorter()
+{
+    mbIsValid = false;
+
+    ReleaseListeners();
+
+    // Dispose model, view and controller to avoid calls between them when
+    // they are being destructed and one or two of them are already gone.
+    mpSlideSorterController->Dispose();
+    mpSlideSorterView->Dispose();
+    mpSlideSorterModel->Dispose();
+
+    // Reset the auto pointers explicitly to control the order of destruction.
+    mpSlideSorterController.reset();
+    mpSlideSorterView.reset();
+    mpSlideSorterModel.reset();
+
+    mpHorizontalScrollBar.reset();
+    mpVerticalScrollBar.reset();
+    mpScrollBarBox.reset();
+}
+
+model::SlideSorterModel& SlideSorter::GetModel() const
+{
+    assert(mpSlideSorterModel);
+    return *mpSlideSorterModel;
+}
+
+view::SlideSorterView& SlideSorter::GetView() const
+{
+    assert(mpSlideSorterView);
+    return *mpSlideSorterView;
+}
+
+controller::SlideSorterController& SlideSorter::GetController() const
+{
+    assert(mpSlideSorterController);
+    return *mpSlideSorterController;
+}
+
+Reference<frame::XController> SlideSorter::GetXController() const
+{
+    Reference<frame::XController> xController(mxControllerWeak);
+    return xController;
+}
+
+void SlideSorter::Paint (const ::tools::Rectangle& rRepaintArea)
+{
+    GetController().Paint(
+        rRepaintArea,
+        GetContentWindow());
+}
+
+void SlideSorter::SetupControls()
+{
+    GetVerticalScrollBar()->Show();
+}
+
+void SlideSorter::SetupListeners()
+{
+    sd::Window *pWindow = GetContentWindow().get();
+    if (pWindow)
+    {
+        vcl::Window* pParentWindow = pWindow->GetParent();
+        if (pParentWindow != nullptr)
+            pParentWindow->AddEventListener(
+                LINK(
+                    mpSlideSorterController.get(),
+                    controller::SlideSorterController,
+                    WindowEventHandler));
+        pWindow->AddEventListener(
+            LINK(
+                mpSlideSorterController.get(),
+                controller::SlideSorterController,
+                WindowEventHandler));
+    }
+    Application::AddEventListener(
+        LINK(
+            mpSlideSorterController.get(),
+            controller::SlideSorterController,
+            ApplicationEventHandler));
+
+    mpSlideSorterController->GetScrollBarManager().Connect();
+}
+
+void SlideSorter::ReleaseListeners()
+{
+    mpSlideSorterController->GetScrollBarManager().Disconnect();
+
+    sd::Window *pWindow (GetContentWindow().get());
+    if (pWindow)
+    {
+        pWindow->RemoveEventListener(
+            LINK(mpSlideSorterController.get(),
+                controller::SlideSorterController,
+                WindowEventHandler));
+
+        vcl::Window* pParentWindow = pWindow->GetParent();
+        if (pParentWindow != nullptr)
+            pParentWindow->RemoveEventListener(
+                LINK(mpSlideSorterController.get(),
+                    controller::SlideSorterController,
+                    WindowEventHandler));
+    }
+    Application::RemoveEventListener(
+        LINK(mpSlideSorterController.get(),
+            controller::SlideSorterController,
+            ApplicationEventHandler));
+}
+
+void SlideSorter::CreateModelViewController()
+{
+    mpSlideSorterModel.reset(CreateModel());
+    DBG_ASSERT(mpSlideSorterModel != nullptr, "Can not create model for slide browser");
+
+    mpSlideSorterView.reset(new view::SlideSorterView (*this));
+    mpSlideSorterController.reset(new controller::SlideSorterController(*this));
+
+    // Now that model, view, and controller are constructed, do the
+    // initialization that relies on all three being in place.
+    mpSlideSorterController->Init();
+    mpSlideSorterView->Init();
+}
+
+model::SlideSorterModel* SlideSorter::CreateModel()
+{
+    // Get pointers to the document.
+    ViewShellBase* pViewShellBase = GetViewShellBase();
+    if (pViewShellBase != nullptr)
+    {
+        assert (pViewShellBase->GetDocument() != nullptr);
+
+        return new model::SlideSorterModel(*this);
+    }
+    else
+        return nullptr;
+}
+
+void SlideSorter::ArrangeGUIElements (
+    const Point& rOffset,
+    const Size& rSize)
+{
+    Point aOrigin (rOffset);
+
+    if (rSize.Width()>0
+        && rSize.Height()>0
+        && GetContentWindow()
+        && GetContentWindow()->IsVisible())
+    {
+        // Prevent untimely redraws while the view is not yet correctly
+        // resized.
+        view::SlideSorterView::DrawLock aLock (*this);
+        GetContentWindow()->EnablePaint (false);
+
+        mpSlideSorterController->Resize (::tools::Rectangle(aOrigin, rSize));
+
+        GetContentWindow()->EnablePaint (true);
+    }
+}
+
+void SlideSorter::RelocateToWindow (vcl::Window* pParentWindow)
+{
+   // Stop all animations for they have been started for the old window.
+    mpSlideSorterController->GetAnimator()->RemoveAllAnimations();
+
+    ReleaseListeners();
+
+    if (mpViewShell)
+    {
+        mpViewShell->ViewShell::RelocateToParentWindow(pParentWindow);
+    }
+
+    SetupControls();
+    SetupListeners();
+
+    // For accessibility we have to shortly hide the content window.  This
+    // triggers the construction of a new accessibility object for the new
+    // view shell.  (One is created earlier while the constructor of the base
+    // class is executed.  But because at that time the correct
+    // accessibility object can not be constructed we do that now.)
+    if (mpContentWindow)
+    {
+        mpContentWindow->Hide();
+        mpContentWindow->Show();
+    }
+}
+
+void SlideSorter::SetCurrentFunction (const rtl::Reference<FuPoor>& rpFunction)
+{
+    if (GetViewShell() != nullptr)
+    {
+        GetViewShell()->SetCurrentFunction(rpFunction);
+        GetViewShell()->SetOldFunction(rpFunction);
+    }
+    else
+    {
+        ContentWindow* pWindow = dynamic_cast<ContentWindow*>(GetContentWindow().get());
+        if (pWindow != nullptr)
+            pWindow->SetCurrentFunction(rpFunction);
+    }
+}
+
+std::shared_ptr<controller::Properties> const & SlideSorter::GetProperties() const
+{
+    assert(mpProperties);
+    return mpProperties;
+}
+
+std::shared_ptr<view::Theme> const & SlideSorter::GetTheme() const
+{
+    assert(mpTheme);
+    return mpTheme;
+}
+
+//===== ContentWindow =========================================================
+
+namespace {
+
+ContentWindow::ContentWindow(
+    vcl::Window& rParent,
+    SlideSorter& rSlideSorter)
+    : ::sd::Window(&rParent),
+    mrSlideSorter(rSlideSorter)
+{
+    SetDialogControlFlags(GetDialogControlFlags() & ~DialogControlFlags::WantFocus);
+    SetStyle(GetStyle() | WB_NOPOINTERFOCUS);
+}
+
+void ContentWindow::SetCurrentFunction (const rtl::Reference<FuPoor>& rpFunction)
+{
+    mpCurrentFunction = rpFunction;
+}
+
+void ContentWindow::Paint (vcl::RenderContext& /*rRenderContext*/, const ::tools::Rectangle& rRect)
+{
+    mrSlideSorter.Paint(rRect);
+}
+
+void ContentWindow::KeyInput (const KeyEvent& rEvent)
+{
+    if (mpCurrentFunction.is())
+        mpCurrentFunction->KeyInput(rEvent);
+}
+
+void ContentWindow::MouseMove (const MouseEvent& rEvent)
+{
+    if (mpCurrentFunction.is())
+        mpCurrentFunction->MouseMove(rEvent);
+}
+
+void ContentWindow::MouseButtonUp(const MouseEvent& rEvent)
+{
+    if (mpCurrentFunction.is())
+        mpCurrentFunction->MouseButtonUp(rEvent);
+}
+
+void ContentWindow::MouseButtonDown(const MouseEvent& rEvent)
+{
+    if (mpCurrentFunction.is())
+        mpCurrentFunction->MouseButtonDown(rEvent);
+}
+
+void ContentWindow::Command(const CommandEvent& rEvent)
+{
+    if (mpCurrentFunction.is())
+        mpCurrentFunction->Command(rEvent);
+}
+
+bool ContentWindow::EventNotify(NotifyEvent&)
+{
+    return false;
+}
+
+} // end of anonymous namespace
+
+} // end of namespace ::sd::slidesorter
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/shell/SlideSorterService.cxx b/sd/source/ui/slidesorter/shell/SlideSorterService.cxx
new file mode 100644
index 000000000..a086f3b9e
--- /dev/null
+++ b/sd/source/ui/slidesorter/shell/SlideSorterService.cxx
@@ -0,0 +1,412 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "SlideSorterService.hxx"
+#include <SlideSorter.hxx>
+#include <controller/SlideSorterController.hxx>
+#include <controller/SlsProperties.hxx>
+#include <controller/SlsCurrentSlideManager.hxx>
+#include <model/SlideSorterModel.hxx>
+#include <model/SlsPageDescriptor.hxx>
+#include <view/SlideSorterView.hxx>
+#include <view/SlsLayouter.hxx>
+#include <DrawController.hxx>
+
+#include <comphelper/servicehelper.hxx>
+#include <toolkit/helper/vclunohelper.hxx>
+#include <com/sun/star/lang/XUnoTunnel.hpp>
+
+using namespace ::com::sun::star;
+using namespace ::com::sun::star::uno;
+using namespace ::com::sun::star::drawing::framework;
+using ::sd::slidesorter::view::Layouter;
+
+namespace sd::slidesorter {
+
+//===== SlideSorterService ==========================================================
+
+SlideSorterService::SlideSorterService()
+{
+}
+
+SlideSorterService::~SlideSorterService()
+{
+}
+
+void SlideSorterService::disposing(std::unique_lock<std::mutex>&)
+{
+    mpSlideSorter.reset();
+
+    if (mxParentWindow.is())
+    {
+        mxParentWindow->removeWindowListener(this);
+    }
+}
+
+//----- XInitialization -------------------------------------------------------
+
+void SAL_CALL SlideSorterService::initialize (const Sequence<Any>& rArguments)
+{
+    ThrowIfDisposed();
+
+    if (rArguments.getLength() != 3)
+    {
+        throw RuntimeException("SlideSorterService: invalid number of arguments",
+            static_cast<drawing::XDrawView*>(this));
+    }
+
+    mxViewId.set(rArguments[0], UNO_QUERY_THROW);
+
+    // Get the XController.
+    Reference<frame::XController> xController (rArguments[1], UNO_QUERY_THROW);
+
+    // Tunnel through the controller to obtain a ViewShellBase.
+    ViewShellBase* pBase = nullptr;
+    Reference<lang::XUnoTunnel> xTunnel (xController, UNO_QUERY_THROW);
+    ::sd::DrawController* pController = comphelper::getFromUnoTunnel<sd::DrawController>(xTunnel);
+    if (pController != nullptr)
+        pBase = pController->GetViewShellBase();
+
+    // Get the parent window.
+    mxParentWindow.set(rArguments[2], UNO_QUERY_THROW);
+    VclPtr<vcl::Window> pParentWindow = VCLUnoHelper::GetWindow(mxParentWindow);
+
+    mxParentWindow->addWindowListener(this);
+
+    if (pBase != nullptr && pParentWindow)
+        mpSlideSorter = SlideSorter::CreateSlideSorter(
+            *pBase,
+            *pParentWindow);
+
+    Resize();
+}
+
+//----- XView -----------------------------------------------------------------
+
+Reference<XResourceId> SAL_CALL SlideSorterService::getResourceId()
+{
+    return mxViewId;
+}
+
+sal_Bool SAL_CALL SlideSorterService::isAnchorOnly()
+{
+    return false;
+}
+
+//----- XWindowListener -------------------------------------------------------
+
+void SAL_CALL SlideSorterService::windowResized (const awt::WindowEvent&)
+{
+    ThrowIfDisposed();
+
+    Resize();
+}
+
+void SAL_CALL SlideSorterService::windowMoved (const awt::WindowEvent&) {}
+
+void SAL_CALL SlideSorterService::windowShown (const lang::EventObject&)
+{
+    ThrowIfDisposed();
+    Resize();
+}
+
+void SAL_CALL SlideSorterService::windowHidden (const lang::EventObject&)
+{
+    ThrowIfDisposed();
+}
+
+//----- lang::XEventListener --------------------------------------------------
+
+void SAL_CALL SlideSorterService::disposing (const lang::EventObject& rEvent)
+{
+    if (rEvent.Source == mxParentWindow)
+        mxParentWindow = nullptr;
+}
+
+//----- XDrawView -------------------------------------------------------------
+
+void SAL_CALL SlideSorterService::setCurrentPage(const Reference<drawing::XDrawPage>& rxSlide)
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter != nullptr)
+        mpSlideSorter->GetController().GetCurrentSlideManager()->NotifyCurrentSlideChange(
+            mpSlideSorter->GetModel().GetIndex(rxSlide));
+}
+
+Reference<drawing::XDrawPage> SAL_CALL SlideSorterService::getCurrentPage()
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter != nullptr)
+        return mpSlideSorter->GetController().GetCurrentSlideManager()->GetCurrentSlide()->GetXDrawPage();
+    else
+        return nullptr;
+}
+
+//----- attributes ------------------------------------------------------------
+
+Reference<container::XIndexAccess> SAL_CALL SlideSorterService::getDocumentSlides()
+{
+    return mpSlideSorter->GetModel().GetDocumentSlides();
+}
+
+void SAL_CALL SlideSorterService::setDocumentSlides (
+    const Reference<container::XIndexAccess >& rxSlides)
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter != nullptr && mpSlideSorter->IsValid())
+        mpSlideSorter->GetController().SetDocumentSlides(rxSlides);
+}
+
+sal_Bool SAL_CALL SlideSorterService::getIsHighlightCurrentSlide()
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter == nullptr || !mpSlideSorter->IsValid())
+        return false;
+    else
+        return mpSlideSorter->GetProperties()->IsHighlightCurrentSlide();
+}
+
+void SAL_CALL SlideSorterService::setIsHighlightCurrentSlide (sal_Bool bValue)
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter != nullptr && mpSlideSorter->IsValid())
+    {
+        mpSlideSorter->GetProperties()->SetHighlightCurrentSlide(bValue);
+        controller::SlideSorterController::ModelChangeLock aLock (mpSlideSorter->GetController());
+        mpSlideSorter->GetController().HandleModelChange();
+    }
+}
+
+sal_Bool SAL_CALL SlideSorterService::getIsShowSelection()
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter == nullptr || !mpSlideSorter->IsValid())
+        return false;
+    else
+        return mpSlideSorter->GetProperties()->IsShowSelection();
+}
+
+void SAL_CALL SlideSorterService::setIsShowSelection (sal_Bool bValue)
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter != nullptr && mpSlideSorter->IsValid())
+        mpSlideSorter->GetProperties()->SetShowSelection(bValue);
+}
+
+sal_Bool SAL_CALL SlideSorterService::getIsShowFocus()
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter == nullptr || !mpSlideSorter->IsValid())
+        return false;
+    else
+        return mpSlideSorter->GetProperties()->IsShowFocus();
+}
+
+void SAL_CALL SlideSorterService::setIsShowFocus (sal_Bool bValue)
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter != nullptr && mpSlideSorter->IsValid())
+        mpSlideSorter->GetProperties()->SetShowFocus(bValue);
+}
+
+sal_Bool SAL_CALL SlideSorterService::getIsCenterSelection()
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter == nullptr || !mpSlideSorter->IsValid())
+        return false;
+    else
+        return mpSlideSorter->GetProperties()->IsCenterSelection();
+}
+
+void SAL_CALL SlideSorterService::setIsCenterSelection (sal_Bool bValue)
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter != nullptr && mpSlideSorter->IsValid())
+        mpSlideSorter->GetProperties()->SetCenterSelection(bValue);
+}
+
+sal_Bool SAL_CALL SlideSorterService::getIsSuspendPreviewUpdatesDuringFullScreenPresentation()
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter == nullptr || !mpSlideSorter->IsValid())
+        return true;
+    else
+        return mpSlideSorter->GetProperties()
+            ->IsSuspendPreviewUpdatesDuringFullScreenPresentation();
+}
+
+void SAL_CALL SlideSorterService::setIsSuspendPreviewUpdatesDuringFullScreenPresentation (
+    sal_Bool bValue)
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter != nullptr && mpSlideSorter->IsValid())
+        mpSlideSorter->GetProperties()
+            ->SetSuspendPreviewUpdatesDuringFullScreenPresentation(bValue);
+}
+
+sal_Bool SAL_CALL SlideSorterService::getIsOrientationVertical()
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter == nullptr || !mpSlideSorter->IsValid())
+        return true;
+    else
+        return mpSlideSorter->GetView().GetOrientation() != Layouter::HORIZONTAL;
+}
+
+void SAL_CALL SlideSorterService::setIsOrientationVertical (sal_Bool bValue)
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter != nullptr && mpSlideSorter->IsValid())
+        mpSlideSorter->GetView().SetOrientation(bValue
+            ? Layouter::GRID
+            : Layouter::HORIZONTAL);
+}
+
+sal_Bool SAL_CALL SlideSorterService::getIsSmoothScrolling()
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter == nullptr || !mpSlideSorter->IsValid())
+        return false;
+    else
+        return mpSlideSorter->GetProperties()->IsSmoothSelectionScrolling();
+}
+
+void SAL_CALL SlideSorterService::setIsSmoothScrolling (sal_Bool bValue)
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter != nullptr && mpSlideSorter->IsValid())
+        mpSlideSorter->GetProperties()->SetSmoothSelectionScrolling(bValue);
+}
+
+sal_Int32 SAL_CALL SlideSorterService::getBackgroundColor()
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter == nullptr || !mpSlideSorter->IsValid())
+        return util::Color();
+    else
+        return util::Color(
+            mpSlideSorter->GetProperties()->GetBackgroundColor());
+}
+
+void SAL_CALL SlideSorterService::setBackgroundColor (sal_Int32 aBackgroundColor)
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter != nullptr && mpSlideSorter->IsValid())
+        mpSlideSorter->GetProperties()->SetBackgroundColor(Color(ColorTransparency, aBackgroundColor));
+}
+
+sal_Int32 SAL_CALL SlideSorterService::getTextColor()
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter == nullptr || !mpSlideSorter->IsValid())
+        return util::Color();
+    else
+        return util::Color(
+            mpSlideSorter->GetProperties()->GetTextColor());
+}
+
+void SAL_CALL SlideSorterService::setTextColor (sal_Int32 aTextColor)
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter != nullptr && mpSlideSorter->IsValid())
+        mpSlideSorter->GetProperties()->SetTextColor(Color(ColorTransparency, aTextColor));
+}
+
+sal_Int32 SAL_CALL SlideSorterService::getSelectionColor()
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter == nullptr || !mpSlideSorter->IsValid())
+        return util::Color();
+    else
+        return util::Color(
+            mpSlideSorter->GetProperties()->GetSelectionColor());
+}
+
+void SAL_CALL SlideSorterService::setSelectionColor (sal_Int32 aSelectionColor)
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter != nullptr && mpSlideSorter->IsValid())
+        mpSlideSorter->GetProperties()->SetSelectionColor(Color(ColorTransparency, aSelectionColor));
+}
+
+sal_Int32 SAL_CALL SlideSorterService::getHighlightColor()
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter == nullptr || !mpSlideSorter->IsValid())
+        return util::Color();
+    else
+        return util::Color(
+            mpSlideSorter->GetProperties()->GetHighlightColor());
+}
+
+void SAL_CALL SlideSorterService::setHighlightColor (sal_Int32 aHighlightColor)
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter != nullptr && mpSlideSorter->IsValid())
+        mpSlideSorter->GetProperties()->SetHighlightColor(Color(ColorTransparency, aHighlightColor));
+}
+
+sal_Bool SAL_CALL SlideSorterService::getIsUIReadOnly()
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter == nullptr || !mpSlideSorter->IsValid())
+        return true;
+    else
+        return mpSlideSorter->GetProperties()->IsUIReadOnly();
+}
+
+void SAL_CALL SlideSorterService::setIsUIReadOnly (sal_Bool bIsUIReadOnly)
+{
+    ThrowIfDisposed();
+    if (mpSlideSorter != nullptr && mpSlideSorter->IsValid())
+        mpSlideSorter->GetProperties()->SetUIReadOnly(bIsUIReadOnly);
+}
+
+void SlideSorterService::Resize()
+{
+    if (mxParentWindow.is())
+    {
+        awt::Rectangle aWindowBox = mxParentWindow->getPosSize();
+        mpSlideSorter->ArrangeGUIElements(
+            Point(0,0),
+            Size(aWindowBox.Width, aWindowBox.Height));
+    }
+}
+
+void SlideSorterService::ThrowIfDisposed()
+{
+    if (SlideSorterServiceInterfaceBase::m_bDisposed)
+    {
+        throw lang::DisposedException ("SlideSorterService object has already been disposed",
+            static_cast<drawing::XDrawView*>(this));
+    }
+}
+
+} // end of namespace ::sd::slidesorter
+
+
+extern "C" SAL_DLLPUBLIC_EXPORT css::uno::XInterface*
+com_sun_star_comp_Draw_SlideSorter_get_implementation(css::uno::XComponentContext* /*context*/,
+                                                      css::uno::Sequence<css::uno::Any> const &)
+{
+    return cppu::acquire(new sd::slidesorter::SlideSorterService);
+}
+
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/shell/SlideSorterService.hxx b/sd/source/ui/slidesorter/shell/SlideSorterService.hxx
new file mode 100644
index 000000000..579a5bae5
--- /dev/null
+++ b/sd/source/ui/slidesorter/shell/SlideSorterService.hxx
@@ -0,0 +1,153 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <com/sun/star/awt/XWindowListener.hpp>
+#include <com/sun/star/drawing/XSlideSorterBase.hpp>
+#include <com/sun/star/lang/XInitialization.hpp>
+#include <comphelper/compbase.hxx>
+#include <memory>
+
+namespace com::sun::star::awt { class XWindow; }
+
+namespace sd::slidesorter {
+
+typedef comphelper::WeakComponentImplHelper <
+    css::drawing::XSlideSorterBase,
+    css::lang::XInitialization,
+    css::awt::XWindowListener
+> SlideSorterServiceInterfaceBase;
+
+class SlideSorter;
+
+/** Implementation of the com.sun.star.drawing.SlideSorter service.
+*/
+class SlideSorterService
+    : public SlideSorterServiceInterfaceBase
+{
+public:
+    explicit SlideSorterService();
+    virtual ~SlideSorterService() override;
+    SlideSorterService(const SlideSorterService&) = delete;
+    SlideSorterService& operator=(const SlideSorterService&) = delete;
+    virtual void disposing(std::unique_lock<std::mutex>&) override;
+
+    // XInitialization
+
+    virtual void SAL_CALL initialize (const css::uno::Sequence<css::uno::Any>& rArguments) override;
+
+    // XResourceId
+
+    css::uno::Reference<css::drawing::framework::XResourceId> SAL_CALL getResourceId() override;
+
+    sal_Bool SAL_CALL isAnchorOnly() override;
+
+    // XWindowListener
+
+    virtual void SAL_CALL windowResized (const css::awt::WindowEvent& rEvent) override;
+
+    virtual void SAL_CALL windowMoved (const css::awt::WindowEvent& rEvent) override;
+
+    virtual void SAL_CALL windowShown (const css::lang::EventObject& rEvent) override;
+
+    virtual void SAL_CALL windowHidden (const css::lang::EventObject& rEvent) override;
+
+    // lang::XEventListener
+    virtual void SAL_CALL disposing (const css::lang::EventObject& rEvent) override;
+
+    // XDrawView
+
+    virtual void SAL_CALL setCurrentPage(
+        const css::uno::Reference<css::drawing::XDrawPage>& rxSlide) override;
+
+    virtual css::uno::Reference<css::drawing::XDrawPage> SAL_CALL getCurrentPage() override;
+
+    // Attributes
+
+    virtual css::uno::Reference<css::container::XIndexAccess> SAL_CALL getDocumentSlides() override;
+
+    virtual void SAL_CALL setDocumentSlides (
+        const css::uno::Reference<css::container::XIndexAccess >& rxSlides) override;
+
+    virtual sal_Bool SAL_CALL getIsHighlightCurrentSlide() override;
+
+    virtual void SAL_CALL setIsHighlightCurrentSlide (sal_Bool bIsHighlightCurrentSlide) override;
+
+    virtual sal_Bool SAL_CALL getIsShowSelection() override;
+
+    virtual void SAL_CALL setIsShowSelection (sal_Bool bIsShowSelection) override;
+
+    virtual sal_Bool SAL_CALL getIsCenterSelection() override;
+
+    virtual void SAL_CALL setIsCenterSelection (sal_Bool bIsCenterSelection) override;
+
+    virtual sal_Bool SAL_CALL getIsSuspendPreviewUpdatesDuringFullScreenPresentation() override;
+
+    virtual void SAL_CALL setIsSuspendPreviewUpdatesDuringFullScreenPresentation (
+        sal_Bool bIsSuspendPreviewUpdatesDuringFullScreenPresentation) override;
+
+    virtual sal_Bool SAL_CALL getIsOrientationVertical() override;
+
+    virtual void SAL_CALL setIsOrientationVertical (sal_Bool bIsOrientationVertical) override;
+
+    virtual sal_Bool SAL_CALL getIsSmoothScrolling() override;
+
+    virtual void SAL_CALL setIsSmoothScrolling (sal_Bool bIsOrientationVertical) override;
+
+    virtual sal_Int32 SAL_CALL getBackgroundColor() override;
+
+    virtual void SAL_CALL setBackgroundColor (sal_Int32 aBackgroundColor) override;
+
+    virtual sal_Int32 SAL_CALL getTextColor() override;
+
+    virtual void SAL_CALL setTextColor (sal_Int32 aTextColor) override;
+
+    virtual sal_Int32 SAL_CALL getSelectionColor() override;
+
+    virtual void SAL_CALL setSelectionColor (sal_Int32 aSelectionColor) override;
+
+    virtual sal_Int32 SAL_CALL getHighlightColor() override;
+
+    virtual void SAL_CALL setHighlightColor (sal_Int32 aHighlightColor) override;
+
+    virtual sal_Bool SAL_CALL getIsUIReadOnly() override;
+
+    virtual void SAL_CALL setIsUIReadOnly (sal_Bool bIsUIReadOnly) override;
+
+    virtual sal_Bool SAL_CALL getIsShowFocus() override;
+
+    virtual void SAL_CALL setIsShowFocus (sal_Bool bIsShowFocus) override;
+
+private:
+    std::shared_ptr<SlideSorter> mpSlideSorter;
+    css::uno::Reference<css::drawing::framework::XResourceId> mxViewId;
+    css::uno::Reference<css::awt::XWindow> mxParentWindow;
+
+    void Resize();
+
+    /** @throws css::lang::DisposedException when the object has already been
+        disposed.
+    */
+    void ThrowIfDisposed();
+};
+
+} // end of namespace ::sd::slidesorter
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/shell/SlideSorterViewShell.cxx b/sd/source/ui/slidesorter/shell/SlideSorterViewShell.cxx
new file mode 100644
index 000000000..af5bd5791
--- /dev/null
+++ b/sd/source/ui/slidesorter/shell/SlideSorterViewShell.cxx
@@ -0,0 +1,924 @@
+#/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <SlideSorterViewShell.hxx>
+#include <ViewShellImplementation.hxx>
+
+#include <SlideSorter.hxx>
+#include <controller/SlideSorterController.hxx>
+#include <controller/SlsClipboard.hxx>
+#include <controller/SlsScrollBarManager.hxx>
+#include <controller/SlsPageSelector.hxx>
+#include <controller/SlsSlotManager.hxx>
+#include <controller/SlsCurrentSlideManager.hxx>
+#include <controller/SlsSelectionManager.hxx>
+#include <view/SlideSorterView.hxx>
+#include <view/SlsLayouter.hxx>
+#include <model/SlideSorterModel.hxx>
+#include <model/SlsPageDescriptor.hxx>
+#include <framework/FrameworkHelper.hxx>
+#include <ViewShellBase.hxx>
+#include <drawdoc.hxx>
+#include <sdpage.hxx>
+#include <app.hrc>
+#include <AccessibleSlideSorterView.hxx>
+#include <DrawDocShell.hxx>
+#include <DrawViewShell.hxx>
+#include <FrameView.hxx>
+#include <SdUnoSlideView.hxx>
+#include <ViewShellManager.hxx>
+#include <Window.hxx>
+#include <drawview.hxx>
+#include <sfx2/msg.hxx>
+#include <sfx2/objface.hxx>
+#include <sfx2/viewfrm.hxx>
+#include <sfx2/bindings.hxx>
+#include <sfx2/request.hxx>
+#include <sfx2/sidebar/SidebarChildWindow.hxx>
+#include <sfx2/devtools/DevelopmentToolChildWindow.hxx>
+#include <svx/svxids.hrc>
+#include <vcl/EnumContext.hxx>
+#include <svx/sidebar/ContextChangeEventMultiplexer.hxx>
+#include <tools/diagnose_ex.h>
+#include <sfx2/sidebar/SidebarController.hxx>
+
+using namespace ::sd::slidesorter;
+#define ShellClass_SlideSorterViewShell
+#include <sdslots.hxx>
+
+using namespace ::com::sun::star;
+using namespace ::com::sun::star::uno;
+using namespace ::com::sun::star::drawing::framework;
+
+using ::sd::framework::FrameworkHelper;
+using ::vcl::EnumContext;
+using namespace sfx2::sidebar;
+
+namespace sd::slidesorter {
+
+namespace {
+
+bool inChartContext(const sd::View* pView)
+{
+    if (!pView)
+        return false;
+
+    SfxViewShell* pViewShell = pView->GetSfxViewShell();
+    SidebarController* pSidebar = SidebarController::GetSidebarControllerForView(pViewShell);
+    if (pSidebar)
+        return pSidebar->hasChartContextCurrently();
+
+    return false;
+}
+
+} // anonymous namespace
+
+
+SFX_IMPL_INTERFACE(SlideSorterViewShell, SfxShell)
+
+void SlideSorterViewShell::InitInterface_Impl()
+{
+    GetStaticInterface()->RegisterChildWindow(::sfx2::sidebar::SidebarChildWindow::GetChildWindowId());
+    GetStaticInterface()->RegisterChildWindow(DevelopmentToolChildWindow::GetChildWindowId());
+}
+
+
+std::shared_ptr<SlideSorterViewShell> SlideSorterViewShell::Create (
+    SfxViewFrame* pFrame,
+    ViewShellBase& rViewShellBase,
+    vcl::Window* pParentWindow,
+    FrameView* pFrameViewArgument)
+{
+    std::shared_ptr<SlideSorterViewShell> pViewShell;
+    try
+    {
+        pViewShell.reset(
+            new SlideSorterViewShell(pFrame,rViewShellBase,pParentWindow,pFrameViewArgument));
+        pViewShell->Initialize();
+        if (pViewShell->mpSlideSorter == nullptr)
+            pViewShell.reset();
+    }
+    catch(Exception&)
+    {
+        pViewShell.reset();
+    }
+    return pViewShell;
+}
+
+SlideSorterViewShell::SlideSorterViewShell (
+    SfxViewFrame* /*pFrame*/,
+    ViewShellBase& rViewShellBase,
+    vcl::Window* pParentWindow,
+    FrameView* pFrameViewArgument)
+    : ViewShell (pParentWindow, rViewShellBase),
+      mbIsArrangeGUIElementsPending(true)
+{
+    GetContentWindow()->set_id("slidesorter");
+    meShellType = ST_SLIDE_SORTER;
+
+    if (pFrameViewArgument != nullptr)
+        mpFrameView = pFrameViewArgument;
+    else
+        mpFrameView = new FrameView(GetDoc());
+    GetFrameView()->Connect();
+
+    SetName ("SlideSorterViewShell");
+
+    pParentWindow->SetStyle(pParentWindow->GetStyle() | WB_DIALOGCONTROL);
+}
+
+SlideSorterViewShell::~SlideSorterViewShell()
+{
+    DisposeFunctions();
+
+    try
+    {
+        ::sd::Window* pWindow = GetActiveWindow();
+        if (pWindow!=nullptr)
+        {
+            css::uno::Reference<css::lang::XComponent> xComponent (
+                    pWindow->GetAccessible(false),
+                    css::uno::UNO_QUERY);
+            if (xComponent.is())
+                xComponent->dispose();
+        }
+    }
+    catch( css::uno::Exception& )
+    {
+        TOOLS_WARN_EXCEPTION( "sd", "sd::SlideSorterViewShell::~SlideSorterViewShell()" );
+    }
+    GetFrameView()->Disconnect();
+}
+
+void SlideSorterViewShell::Initialize()
+{
+    mpSlideSorter = SlideSorter::CreateSlideSorter(
+        *this,
+        mpContentWindow,
+        mpHorizontalScrollBar,
+        mpVerticalScrollBar,
+        mpScrollBarBox);
+    mpView = &mpSlideSorter->GetView();
+
+    doShow();
+
+    SetPool( &GetDoc()->GetPool() );
+    SetUndoManager( GetDoc()->GetDocSh()->GetUndoManager() );
+
+    // For accessibility we have to shortly hide the content window.
+    // This triggers the construction of a new accessibility object for
+    // the new view shell.  (One is created earlier while the constructor
+    // of the base class is executed.  At that time the correct
+    // accessibility object can not be constructed.)
+    sd::Window *pWindow (mpSlideSorter->GetContentWindow().get());
+    if (pWindow)
+    {
+        pWindow->Hide();
+        pWindow->Show();
+    }
+}
+
+void SlideSorterViewShell::Init (bool bIsMainViewShell)
+{
+    ViewShell::Init(bIsMainViewShell);
+
+    // since the updatePageList will show focus, the window.show() must be called ahead. This show is deferred from Init()
+    ::sd::Window* pActiveWindow = GetActiveWindow();
+    if (pActiveWindow)
+        pActiveWindow->Show();
+    mpSlideSorter->GetModel().UpdatePageList();
+
+    if (mpContentWindow)
+        mpContentWindow->SetViewShell(this);
+}
+
+SlideSorterViewShell* SlideSorterViewShell::GetSlideSorter (ViewShellBase& rBase)
+{
+    SlideSorterViewShell* pViewShell = nullptr;
+
+    // Test the center and left pane for showing a slide sorter.
+    OUString aPaneURLs[] = {
+        FrameworkHelper::msCenterPaneURL,
+        FrameworkHelper::msFullScreenPaneURL,
+        FrameworkHelper::msLeftImpressPaneURL,
+        FrameworkHelper::msLeftDrawPaneURL,
+        OUString()};
+
+    try
+    {
+        std::shared_ptr<FrameworkHelper> pFrameworkHelper (FrameworkHelper::Instance(rBase));
+        if (pFrameworkHelper->IsValid())
+            for (int i=0; pViewShell==nullptr && !aPaneURLs[i].isEmpty(); ++i)
+            {
+                pViewShell = dynamic_cast<SlideSorterViewShell*>(
+                    pFrameworkHelper->GetViewShell(aPaneURLs[i]).get());
+            }
+    }
+    catch (RuntimeException&)
+    {}
+
+    return pViewShell;
+}
+
+Reference<drawing::XDrawSubController> SlideSorterViewShell::CreateSubController()
+{
+    Reference<drawing::XDrawSubController> xSubController;
+
+    if (IsMainViewShell())
+    {
+        // Create uno controller for the main view shell.
+        xSubController.set( new SdUnoSlideView( *mpSlideSorter));
+    }
+
+    return xSubController;
+}
+
+/** If there is a valid controller then create a new instance of
+    <type>AccessibleSlideSorterView</type>.  Otherwise delegate this call
+    to the base class to return a default object (probably an empty
+    reference).
+*/
+css::uno::Reference<css::accessibility::XAccessible>
+    SlideSorterViewShell::CreateAccessibleDocumentView (::sd::Window* pWindow)
+{
+    // When the view is not set then the initialization is not yet complete
+    // and we can not yet provide an accessibility object.
+    if (mpView == nullptr || mpSlideSorter == nullptr)
+        return nullptr;
+
+    assert(mpSlideSorter);
+
+    rtl::Reference<::accessibility::AccessibleSlideSorterView> pAccessibleView =
+    new ::accessibility::AccessibleSlideSorterView(
+        *mpSlideSorter,
+        pWindow);
+
+    pAccessibleView->Init();
+
+    return pAccessibleView;
+}
+
+void SlideSorterViewShell::SwitchViewFireFocus(const css::uno::Reference< css::accessibility::XAccessible >& xAcc )
+{
+    if (xAcc)
+    {
+        ::accessibility::AccessibleSlideSorterView* pBase = static_cast< ::accessibility::AccessibleSlideSorterView* >(xAcc.get());
+        if (pBase)
+        {
+            pBase->SwitchViewActivated();
+        }
+    }
+}
+
+SlideSorter& SlideSorterViewShell::GetSlideSorter() const
+{
+    assert(mpSlideSorter);
+    return *mpSlideSorter;
+}
+
+bool SlideSorterViewShell::RelocateToParentWindow (vcl::Window* pParentWindow)
+{
+    assert(mpSlideSorter);
+    if ( ! mpSlideSorter)
+        return false;
+
+    mpSlideSorter->RelocateToWindow(pParentWindow);
+    ReadFrameViewData(mpFrameView);
+
+    return true;
+}
+
+SfxUndoManager* SlideSorterViewShell::ImpGetUndoManager() const
+{
+    SfxShell* pObjectBar = GetViewShellBase().GetViewShellManager()->GetTopShell();
+    if (pObjectBar != nullptr)
+    {
+        // When it exists then return the undo manager of the currently
+        // active object bar.  The object bar is missing when the
+        // SlideSorterViewShell is not the main view shell.
+        return pObjectBar->GetUndoManager();
+    }
+    else
+    {
+        // Return the undo manager of this  shell when there is no object or
+        // tool bar.
+        return const_cast<SlideSorterViewShell*>(this)->GetUndoManager();
+    }
+}
+
+SdPage* SlideSorterViewShell::getCurrentPage() const
+{
+    // since SlideSorterViewShell::GetActualPage() currently also
+    // returns master pages, which is a wrong behaviour for GetActualPage(),
+    // we can just use that for now
+    return const_cast<SlideSorterViewShell*>(this)->GetActualPage();
+}
+
+SdPage* SlideSorterViewShell::GetActualPage()
+{
+    SdPage* pCurrentPage = nullptr;
+
+    // 1. Try to get the current page from the view shell in the center pane
+    // (if we are that not ourself).
+    if ( ! IsMainViewShell())
+    {
+        std::shared_ptr<ViewShell> pMainViewShell = GetViewShellBase().GetMainViewShell();
+        if (pMainViewShell != nullptr)
+            pCurrentPage = pMainViewShell->GetActualPage();
+    }
+
+    if (pCurrentPage == nullptr)
+    {
+        model::SharedPageDescriptor pDescriptor (
+            mpSlideSorter->GetController().GetCurrentSlideManager()->GetCurrentSlide());
+        if (pDescriptor)
+            pCurrentPage = pDescriptor->GetPage();
+    }
+
+    return pCurrentPage;
+}
+
+void SlideSorterViewShell::GetMenuState ( SfxItemSet& rSet)
+{
+    ViewShell::GetMenuState(rSet);
+    assert(mpSlideSorter);
+    mpSlideSorter->GetController().GetSlotManager()->GetMenuState(rSet);
+}
+
+void SlideSorterViewShell::GetClipboardState ( SfxItemSet& rSet)
+{
+    ViewShell::GetMenuState(rSet);
+    assert(mpSlideSorter);
+    mpSlideSorter->GetController().GetSlotManager()->GetClipboardState(rSet);
+}
+
+void SlideSorterViewShell::ExecCtrl (SfxRequest& rRequest)
+{
+    assert(mpSlideSorter);
+    mpSlideSorter->GetController().ExecCtrl(rRequest);
+}
+
+void SlideSorterViewShell::GetCtrlState (SfxItemSet& rSet)
+{
+    assert(mpSlideSorter);
+    mpSlideSorter->GetController().GetCtrlState(rSet);
+}
+
+void SlideSorterViewShell::FuSupport (SfxRequest& rRequest)
+{
+    assert(mpSlideSorter);
+    mpSlideSorter->GetController().FuSupport(rRequest);
+}
+
+/** We have to handle those slot calls here that need to have access to
+    private or protected members and methods of this class.
+*/
+void SlideSorterViewShell::FuTemporary (SfxRequest& rRequest)
+{
+    assert(mpSlideSorter);
+    switch (rRequest.GetSlot())
+    {
+        case SID_MODIFYPAGE:
+        {
+            SdPage* pCurrentPage = GetActualPage();
+            if (pCurrentPage != nullptr)
+                mpImpl->ProcessModifyPageSlot (
+                    rRequest,
+                    pCurrentPage,
+                    PageKind::Standard);
+            Cancel();
+            rRequest.Done ();
+        }
+        break;
+
+        default:
+            mpSlideSorter->GetController().FuTemporary(rRequest);
+            break;
+    }
+}
+
+void SlideSorterViewShell::GetStatusBarState (SfxItemSet& rSet)
+{
+    assert(mpSlideSorter);
+    mpSlideSorter->GetController().GetStatusBarState(rSet);
+}
+
+void SlideSorterViewShell::FuPermanent (SfxRequest& rRequest)
+{
+    assert(mpSlideSorter);
+    mpSlideSorter->GetController().FuPermanent(rRequest);
+}
+
+void SlideSorterViewShell::GetAttrState (SfxItemSet& rSet)
+{
+    assert(mpSlideSorter);
+    mpSlideSorter->GetController().GetAttrState(rSet);
+}
+
+void SlideSorterViewShell::ExecStatusBar (SfxRequest& )
+{
+}
+
+void SlideSorterViewShell::Paint (
+    const ::tools::Rectangle& rBBox,
+    ::sd::Window* pWindow)
+{
+    SetActiveWindow (pWindow);
+    assert(mpSlideSorter);
+    if (mpSlideSorter)
+        mpSlideSorter->GetController().Paint(rBBox,pWindow);
+}
+
+void SlideSorterViewShell::ArrangeGUIElements()
+{
+    if (IsActive())
+    {
+        assert(mpSlideSorter);
+        mpSlideSorter->ArrangeGUIElements(maViewPos, maViewSize);
+        mbIsArrangeGUIElementsPending = false;
+    }
+    else
+        mbIsArrangeGUIElementsPending = true;
+}
+
+void SlideSorterViewShell::Activate (bool bIsMDIActivate)
+{
+    if(inChartContext(GetView()))
+    {
+        // Avoid context changes for chart during activation / deactivation.
+        const bool bIsContextBroadcasterEnabled (SfxShell::SetContextBroadcasterEnabled(false));
+
+        ViewShell::Activate(bIsMDIActivate);
+
+        SfxShell::SetContextBroadcasterEnabled(bIsContextBroadcasterEnabled);
+        return;
+    }
+
+    ViewShell::Activate(bIsMDIActivate);
+    if (mbIsArrangeGUIElementsPending)
+        ArrangeGUIElements();
+
+    // Determine and broadcast the context that belongs to the main view shell.
+    EnumContext::Context eContext = EnumContext::Context::Unknown;
+    std::shared_ptr<ViewShell> pMainViewShell (GetViewShellBase().GetMainViewShell());
+    ViewShell::ShellType eMainViewShellType (
+        pMainViewShell
+            ? pMainViewShell->GetShellType()
+            : ViewShell::ST_NONE);
+    switch (eMainViewShellType)
+    {
+        case ViewShell::ST_IMPRESS:
+        case ViewShell::ST_SLIDE_SORTER:
+        case ViewShell::ST_NOTES:
+        case ViewShell::ST_DRAW:
+            eContext = EnumContext::Context::DrawPage;
+            if( nullptr != dynamic_cast< const DrawViewShell *>( pMainViewShell.get() ))
+            {
+                DrawViewShell* pDrawViewShell = dynamic_cast<DrawViewShell*>(pMainViewShell.get());
+                if (pDrawViewShell != nullptr)
+                    eContext = EnumContext::GetContextEnum(pDrawViewShell->GetSidebarContextName());
+            }
+            break;
+
+        default:
+            break;
+    }
+    ContextChangeEventMultiplexer::NotifyContextChange(
+        &GetViewShellBase(),
+        eContext);
+}
+
+void SlideSorterViewShell::Deactivate (bool /*bIsMDIActivate*/)
+{
+    // Save Settings - Specifically SlidesPerRow to retrieve it later
+    WriteFrameViewData();
+}
+
+void SlideSorterViewShell::Command (
+    const CommandEvent& rEvent,
+    ::sd::Window* pWindow)
+{
+    assert(mpSlideSorter);
+    if ( ! mpSlideSorter->GetController().Command (rEvent, pWindow))
+        ViewShell::Command (rEvent, pWindow);
+}
+
+void SlideSorterViewShell::ReadFrameViewData (FrameView* pFrameView)
+{
+    assert(mpSlideSorter);
+    if (pFrameView != nullptr)
+    {
+        view::SlideSorterView& rView (mpSlideSorter->GetView());
+
+        sal_uInt16 nSlidesPerRow (pFrameView->GetSlidesPerRow());
+        if (nSlidesPerRow > 0
+            && rView.GetOrientation() == view::Layouter::GRID
+            && IsMainViewShell())
+        {
+            rView.GetLayouter().SetColumnCount(nSlidesPerRow,nSlidesPerRow);
+        }
+        if (IsMainViewShell())
+            mpSlideSorter->GetController().GetCurrentSlideManager()->NotifyCurrentSlideChange(
+                mpFrameView->GetSelectedPage());
+        mpSlideSorter->GetController().Rearrange(true);
+
+        // DrawMode for 'main' window
+        if (GetActiveWindow()->GetOutDev()->GetDrawMode() != pFrameView->GetDrawMode() )
+            GetActiveWindow()->GetOutDev()->SetDrawMode( pFrameView->GetDrawMode() );
+    }
+
+    // When this slide sorter is not displayed in the main window then we do
+    // not share the same frame view and have to find other ways to acquire
+    // certain values.
+    if ( ! IsMainViewShell())
+    {
+        std::shared_ptr<ViewShell> pMainViewShell = GetViewShellBase().GetMainViewShell();
+        if (pMainViewShell != nullptr)
+            mpSlideSorter->GetController().GetCurrentSlideManager()->NotifyCurrentSlideChange(
+                pMainViewShell->getCurrentPage());
+    }
+}
+
+void SlideSorterViewShell::WriteFrameViewData()
+{
+    assert(mpSlideSorter);
+    if (mpFrameView == nullptr)
+        return;
+
+    view::SlideSorterView& rView (mpSlideSorter->GetView());
+    mpFrameView->SetSlidesPerRow(static_cast<sal_uInt16>(rView.GetLayouter().GetColumnCount()));
+
+    // DrawMode for 'main' window
+    if( mpFrameView->GetDrawMode() != GetActiveWindow()->GetOutDev()->GetDrawMode() )
+        mpFrameView->SetDrawMode( GetActiveWindow()->GetOutDev()->GetDrawMode() );
+
+    SdPage* pActualPage = GetActualPage();
+    if (pActualPage != nullptr)
+    {
+        if (IsMainViewShell())
+            mpFrameView->SetSelectedPage((pActualPage->GetPageNum()- 1) / 2);
+        // else
+        // The slide sorter is not expected to switch the current page
+        // other than by double clicks.  That is handled separately.
+    }
+    else
+    {
+        // We have no current page to set but at least we can make sure
+        // that the index of the frame view has a legal value.
+        if (mpFrameView->GetSelectedPage() >= mpSlideSorter->GetModel().GetPageCount())
+            mpFrameView->SetSelectedPage(static_cast<sal_uInt16>(mpSlideSorter->GetModel().GetPageCount())-1);
+    }
+}
+
+void SlideSorterViewShell::SetZoom (::tools::Long )
+{
+    // Ignored.
+    // The zoom scale is adapted internally to fit a number of columns in
+    // the window.
+}
+
+void SlideSorterViewShell::SetZoomRect (const ::tools::Rectangle& rZoomRect)
+{
+    assert(mpSlideSorter);
+    Size aPageSize (mpSlideSorter->GetView().GetLayouter().GetPageObjectSize());
+
+    ::tools::Rectangle aRect(rZoomRect);
+
+    if (aRect.GetWidth()  < aPageSize.Width())
+    {
+        ::tools::Long nWidthDiff  = (aPageSize.Width() - aRect.GetWidth()) / 2;
+
+        aRect.AdjustLeft( -nWidthDiff );
+        aRect.AdjustRight(nWidthDiff );
+
+        if (aRect.Left() < 0)
+        {
+            aRect.SetPos(Point(0, aRect.Top()));
+        }
+    }
+
+    if (aRect.GetHeight()  < aPageSize.Height())
+    {
+        ::tools::Long nHeightDiff  = (aPageSize.Height() - aRect.GetHeight()) / 2;
+
+        aRect.AdjustTop( -nHeightDiff );
+        aRect.AdjustBottom(nHeightDiff );
+
+        if (aRect.Top() < 0)
+        {
+            aRect.SetPos(Point(aRect.Left(), 0));
+        }
+    }
+
+    ViewShell::SetZoomRect(aRect);
+
+    GetViewFrame()->GetBindings().Invalidate( SID_ATTR_ZOOM );
+    GetViewFrame()->GetBindings().Invalidate( SID_ATTR_ZOOMSLIDER );
+}
+
+void SlideSorterViewShell::UpdateScrollBars()
+{
+    // Do not call the overwritten method of the base class: We do all the
+    // scroll bar setup by ourselves.
+    mpSlideSorter->GetController().GetScrollBarManager().UpdateScrollBars(true);
+}
+
+void SlideSorterViewShell::StartDrag (
+    const Point& rDragPt,
+    vcl::Window* pWindow )
+{
+    assert(mpSlideSorter);
+    mpSlideSorter->GetController().GetClipboard().StartDrag (
+        rDragPt,
+        pWindow);
+}
+
+sal_Int8 SlideSorterViewShell::AcceptDrop (
+    const AcceptDropEvent& rEvt,
+    DropTargetHelper& rTargetHelper,
+    ::sd::Window* pTargetWindow,
+    sal_uInt16 nPage,
+    SdrLayerID nLayer)
+{
+    assert(mpSlideSorter);
+    return mpSlideSorter->GetController().GetClipboard().AcceptDrop (
+        rEvt,
+        rTargetHelper,
+        pTargetWindow,
+        nPage,
+        nLayer);
+}
+
+sal_Int8 SlideSorterViewShell::ExecuteDrop (
+    const ExecuteDropEvent& rEvt,
+    DropTargetHelper& rTargetHelper,
+    ::sd::Window* pTargetWindow,
+    sal_uInt16 nPage,
+    SdrLayerID nLayer)
+{
+    assert(mpSlideSorter);
+    return mpSlideSorter->GetController().GetClipboard().ExecuteDrop (
+        rEvt,
+        rTargetHelper,
+        pTargetWindow,
+        nPage,
+        nLayer);
+}
+
+std::shared_ptr<SlideSorterViewShell::PageSelection>
+    SlideSorterViewShell::GetPageSelection() const
+{
+    assert(mpSlideSorter);
+    return mpSlideSorter->GetController().GetPageSelector().GetPageSelection();
+}
+
+void SlideSorterViewShell::SetPageSelection (
+    const std::shared_ptr<PageSelection>& rSelection)
+{
+    assert(mpSlideSorter);
+    mpSlideSorter->GetController().GetPageSelector().SetPageSelection(rSelection, true);
+}
+
+void SlideSorterViewShell::AddSelectionChangeListener (
+    const Link<LinkParamNone*,void>& rCallback)
+{
+    assert(mpSlideSorter);
+    mpSlideSorter->GetController().GetSelectionManager()->AddSelectionChangeListener(rCallback);
+}
+
+void SlideSorterViewShell::RemoveSelectionChangeListener (
+    const Link<LinkParamNone*,void>& rCallback)
+{
+    assert(mpSlideSorter);
+    mpSlideSorter->GetController().GetSelectionManager()->RemoveSelectionChangeListener(rCallback);
+}
+
+void SlideSorterViewShell::MainViewEndEditAndUnmarkAll()
+{
+    std::shared_ptr<ViewShell> pMainViewShell = GetViewShellBase().GetMainViewShell();
+    DrawViewShell* pDrawViewShell = dynamic_cast<DrawViewShell*>(pMainViewShell.get());
+    SdrView* pView = pDrawViewShell ? pDrawViewShell->GetDrawView() : nullptr;
+    if (pView)
+    {
+        pView->SdrEndTextEdit();
+        pView->UnmarkAll();
+    }
+}
+
+std::pair<sal_uInt16, sal_uInt16> SlideSorterViewShell::SyncPageSelectionToDocument(const std::shared_ptr<SlideSorterViewShell::PageSelection> &rpSelection)
+{
+    sal_uInt16 firstSelectedPageNo = SAL_MAX_UINT16;
+    sal_uInt16 lastSelectedPageNo = 0;
+
+    GetDoc()->UnselectAllPages();
+    for (auto& rpPage : *rpSelection)
+    {
+        // Check page number
+        sal_uInt16 pageNo = rpPage->GetPageNum();
+        if (pageNo > lastSelectedPageNo)
+            lastSelectedPageNo = pageNo;
+        if (pageNo < firstSelectedPageNo)
+            firstSelectedPageNo = pageNo;
+        GetDoc()->SetSelected(rpPage, true);
+    }
+
+    return std::make_pair(firstSelectedPageNo, lastSelectedPageNo);
+}
+
+void SlideSorterViewShell::ExecMovePageFirst (SfxRequest& /*rReq*/)
+{
+    MainViewEndEditAndUnmarkAll();
+
+    std::shared_ptr<SlideSorterViewShell::PageSelection> xSelection(GetPageSelection());
+
+    // SdDrawDocument MovePages is based on SdPage IsSelected, so
+    // transfer the SlideSorter selection to SdPages
+    SyncPageSelectionToDocument(xSelection);
+
+    // Moves selected pages after page -1
+    GetDoc()->MovePages( sal_uInt16(-1) );
+
+    PostMoveSlidesActions(xSelection);
+}
+
+void SlideSorterViewShell::GetStateMovePageFirst (SfxItemSet& rSet)
+{
+    if ( ! IsMainViewShell())
+    {
+        std::shared_ptr<ViewShell> pMainViewShell = GetViewShellBase().GetMainViewShell();
+        DrawViewShell* pDrawViewShell = dynamic_cast<DrawViewShell*>(pMainViewShell.get());
+        if (pDrawViewShell != nullptr && pDrawViewShell->GetPageKind() == PageKind::Handout)
+        {
+            rSet.DisableItem( SID_MOVE_PAGE_FIRST );
+            rSet.DisableItem( SID_MOVE_PAGE_UP );
+            return;
+        }
+    }
+
+    std::shared_ptr<SlideSorterViewShell::PageSelection> xSelection(GetPageSelection());
+
+    // SdDrawDocument MovePages is based on SdPage IsSelected, so
+    // transfer the SlideSorter selection to SdPages
+    sal_uInt16 firstSelectedPageNo = SyncPageSelectionToDocument(xSelection).first;
+    // Now compute human page number from internal page number
+    firstSelectedPageNo = (firstSelectedPageNo - 1) / 2;
+
+    if (firstSelectedPageNo == 0)
+    {
+        rSet.DisableItem( SID_MOVE_PAGE_FIRST );
+        rSet.DisableItem( SID_MOVE_PAGE_UP );
+    }
+}
+
+void SlideSorterViewShell::ExecMovePageUp (SfxRequest& /*rReq*/)
+{
+    MainViewEndEditAndUnmarkAll();
+
+    std::shared_ptr<SlideSorterViewShell::PageSelection> xSelection(GetPageSelection());
+
+    // SdDrawDocument MovePages is based on SdPage IsSelected, so
+    // transfer the SlideSorter selection to SdPages
+    sal_uInt16 firstSelectedPageNo = SyncPageSelectionToDocument(xSelection).first;
+
+    // In case no slide is selected
+    if (firstSelectedPageNo == SAL_MAX_UINT16)
+        return;
+
+    // Now compute human page number from internal page number
+    firstSelectedPageNo = (firstSelectedPageNo - 1) / 2;
+
+    if (firstSelectedPageNo == 0)
+        return;
+
+    // Move pages before firstSelectedPageNo - 1 (so after firstSelectedPageNo - 2),
+    // remembering that -1 means at first, which is good.
+    GetDoc()->MovePages( firstSelectedPageNo - 2 );
+
+    PostMoveSlidesActions(xSelection);
+}
+
+void SlideSorterViewShell::GetStateMovePageUp (SfxItemSet& rSet)
+{
+    GetStateMovePageFirst(rSet);
+}
+
+void SlideSorterViewShell::ExecMovePageDown (SfxRequest& /*rReq*/)
+{
+    MainViewEndEditAndUnmarkAll();
+
+    std::shared_ptr<SlideSorterViewShell::PageSelection> xSelection(GetPageSelection());
+
+    // SdDrawDocument MovePages is based on SdPage IsSelected, so
+    // transfer the SlideSorter selection to SdPages
+    sal_uInt16 lastSelectedPageNo = SyncPageSelectionToDocument(xSelection).second;
+
+    // Get page number of the last page
+    sal_uInt16 nNoOfPages = GetDoc()->GetSdPageCount(PageKind::Standard);
+
+    // Now compute human page number from internal page number
+    lastSelectedPageNo = (lastSelectedPageNo - 1) / 2;
+    if (lastSelectedPageNo == nNoOfPages - 1)
+        return;
+
+    // Move to position after lastSelectedPageNo
+    GetDoc()->MovePages( lastSelectedPageNo + 1 );
+
+    PostMoveSlidesActions(xSelection);
+}
+
+void SlideSorterViewShell::GetStateMovePageDown (SfxItemSet& rSet)
+{
+    GetStateMovePageLast( rSet );
+}
+
+void SlideSorterViewShell::ExecMovePageLast (SfxRequest& /*rReq*/)
+{
+    MainViewEndEditAndUnmarkAll();
+
+    std::shared_ptr<SlideSorterViewShell::PageSelection> xSelection(GetPageSelection());
+
+    // SdDrawDocument MovePages is based on SdPage IsSelected, so
+    // transfer the SlideSorter selection to SdPages
+    SyncPageSelectionToDocument(xSelection);
+
+    // Get page number of the last page
+    sal_uInt16 nNoOfPages = GetDoc()->GetSdPageCount(PageKind::Standard);
+
+    // Move to position after last page No (=Number of pages - 1)
+    GetDoc()->MovePages( nNoOfPages - 1 );
+
+    PostMoveSlidesActions(xSelection);
+}
+
+void SlideSorterViewShell::GetStateMovePageLast (SfxItemSet& rSet)
+{
+    std::shared_ptr<ViewShell> pMainViewShell = GetViewShellBase().GetMainViewShell();
+    DrawViewShell* pDrawViewShell = dynamic_cast<DrawViewShell*>(pMainViewShell.get());
+    if (pDrawViewShell != nullptr && pDrawViewShell->GetPageKind() == PageKind::Handout)
+    {
+        rSet.DisableItem( SID_MOVE_PAGE_LAST );
+        rSet.DisableItem( SID_MOVE_PAGE_DOWN );
+        return;
+    }
+
+    std::shared_ptr<SlideSorterViewShell::PageSelection> xSelection(GetPageSelection());
+
+    // SdDrawDocument MovePages is based on SdPage IsSelected, so
+    // transfer the SlideSorter selection to SdPages
+    sal_uInt16 lastSelectedPageNo = SyncPageSelectionToDocument(xSelection).second;
+
+    // Get page number of the last page
+    sal_uInt16 nNoOfPages = GetDoc()->GetSdPageCount(PageKind::Standard);
+
+    // Now compute human page number from internal page number
+    lastSelectedPageNo = (lastSelectedPageNo - 1) / 2;
+    if (lastSelectedPageNo == nNoOfPages - 1)
+    {
+        rSet.DisableItem( SID_MOVE_PAGE_LAST );
+        rSet.DisableItem( SID_MOVE_PAGE_DOWN );
+    }
+}
+
+void SlideSorterViewShell::PostMoveSlidesActions(const std::shared_ptr<SlideSorterViewShell::PageSelection> &rpSelection)
+{
+    sal_uInt16 nNoOfPages = GetDoc()->GetSdPageCount(PageKind::Standard);
+    for (sal_uInt16 nPage = 0; nPage < nNoOfPages; nPage++)
+    {
+        SdPage* pPage = GetDoc()->GetSdPage(nPage, PageKind::Standard);
+        GetDoc()->SetSelected(pPage, false);
+    }
+
+    mpSlideSorter->GetController().GetPageSelector().DeselectAllPages();
+    for (const auto& rpPage : *rpSelection)
+    {
+        mpSlideSorter->GetController().GetPageSelector().SelectPage(rpPage);
+    }
+
+    // Refresh toolbar icons
+    SfxBindings& rBindings = GetViewFrame()->GetBindings();
+    rBindings.Invalidate(SID_MOVE_PAGE_FIRST);
+    rBindings.Invalidate(SID_MOVE_PAGE_UP);
+    rBindings.Invalidate(SID_MOVE_PAGE_DOWN);
+    rBindings.Invalidate(SID_MOVE_PAGE_LAST);
+
+}
+
+} // end of namespace ::sd::slidesorter
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/view/SlideSorterView.cxx b/sd/source/ui/slidesorter/view/SlideSorterView.cxx
new file mode 100644
index 000000000..390541e37
--- /dev/null
+++ b/sd/source/ui/slidesorter/view/SlideSorterView.cxx
@@ -0,0 +1,856 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <view/SlideSorterView.hxx>
+
+#include <SlideSorter.hxx>
+#include <ViewShell.hxx>
+#include "SlsViewCacheContext.hxx"
+#include "SlsLayeredDevice.hxx"
+#include <view/SlsLayouter.hxx>
+#include <view/SlsPageObjectLayouter.hxx>
+#include <view/SlsPageObjectPainter.hxx>
+#include <view/SlsILayerPainter.hxx>
+#include <view/SlsToolTip.hxx>
+#include <controller/SlideSorterController.hxx>
+#include <controller/SlsClipboard.hxx>
+#include <model/SlideSorterModel.hxx>
+#include <model/SlsPageEnumerationProvider.hxx>
+#include <model/SlsPageDescriptor.hxx>
+#include <cache/SlsPageCache.hxx>
+#include <cache/SlsPageCacheManager.hxx>
+#include <PaneDockingWindow.hxx>
+
+#include <sdpage.hxx>
+#include <Window.hxx>
+
+#include <comphelper/lok.hxx>
+#include <osl/diagnose.h>
+#include <vcl/svapp.hxx>
+#include <vcl/scrbar.hxx>
+#include <vcl/settings.hxx>
+#include <vcl/graphicfilter.hxx>
+
+#include <algorithm>
+
+//#define DEBUG_TIMING
+#ifdef DEBUG_TIMING
+#include <memory>
+#include <vector>
+#endif
+
+using namespace ::sd::slidesorter::model;
+using namespace ::drawinglayer::primitive2d;
+
+namespace sd::slidesorter::view {
+
+namespace {
+    /** Wrapper around the SlideSorterView that supports the IPainter
+        interface and that allows the LayeredDevice to hold the
+        SlideSorterView (held as unique_ptr by the SlideSorter) as
+        shared_ptr.
+    */
+    class Painter : public ILayerPainter
+    {
+    public:
+        explicit Painter (SlideSorterView& rView) : mrView(rView) {}
+
+        virtual void Paint (OutputDevice& rDevice, const ::tools::Rectangle& rRepaintArea) override
+        {
+            mrView.Paint(rDevice,rRepaintArea);
+        }
+
+        virtual void SetLayerInvalidator (const SharedILayerInvalidator&) override {}
+
+    private:
+        SlideSorterView& mrView;
+    };
+}
+
+namespace {
+
+class BackgroundPainter
+    : public ILayerPainter
+{
+public:
+    explicit BackgroundPainter (const Color& rBackgroundColor) : maBackgroundColor(rBackgroundColor) {}
+    BackgroundPainter(const BackgroundPainter&) = delete;
+    BackgroundPainter& operator=(const BackgroundPainter&) = delete;
+
+    virtual void Paint (OutputDevice& rDevice, const ::tools::Rectangle& rRepaintArea) override
+    {
+        rDevice.SetFillColor(maBackgroundColor);
+        rDevice.SetLineColor();
+        rDevice.DrawRect(rRepaintArea);
+    }
+
+    virtual void SetLayerInvalidator (const SharedILayerInvalidator&) override {}
+
+    void SetColor (const Color& rColor) { maBackgroundColor = rColor; }
+
+private:
+    Color maBackgroundColor;
+};
+
+}
+
+SlideSorterView::SlideSorterView (SlideSorter& rSlideSorter)
+    : ::sd::View (
+          *rSlideSorter.GetModel().GetDocument(),
+          rSlideSorter.GetContentWindow()->GetOutDev(),
+          rSlideSorter.GetViewShell()),
+      mrSlideSorter(rSlideSorter),
+      mrModel(rSlideSorter.GetModel()),
+      mbIsDisposed(false),
+      mpLayouter (new Layouter(rSlideSorter.GetContentWindow(), rSlideSorter.GetTheme())),
+      mbPageObjectVisibilitiesValid (false),
+      mpLayeredDevice(std::make_shared<LayeredDevice>(rSlideSorter.GetContentWindow())),
+      maVisiblePageRange(-1,-1),
+      maPreviewSize(0,0),
+      mbPreciousFlagUpdatePending(true),
+      meOrientation(Layouter::GRID),
+      mpBackgroundPainter(
+          std::make_shared<BackgroundPainter>(mrSlideSorter.GetTheme()->GetColor(Theme::Color_Background))),
+      mpToolTip(new ToolTip(mrSlideSorter)),
+      mbIsRearrangePending(true)
+{
+    // Hide the page that contains the page objects.
+    SetPageVisible (false);
+
+    // Register the background painter on level 1 to avoid the creation of a
+    // background buffer.
+    mpLayeredDevice->RegisterPainter(mpBackgroundPainter, 1);
+
+    // Wrap a shared_ptr-held-wrapper around this view and register it as
+    // painter at the layered device.  There is no explicit destruction: in
+    // the SlideSorterView destructor the layered device is destroyed and
+    // with it the only reference to the wrapper which therefore is also
+    // destroyed.
+    SharedILayerPainter pPainter = std::make_shared<Painter>(*this);
+
+    // The painter is placed on level 1 to avoid buffering.  This should be
+    // a little faster during animations because the previews are painted
+    // directly into the window, not via the buffer.
+    mpLayeredDevice->RegisterPainter(pPainter, 1);
+}
+
+SlideSorterView::~SlideSorterView()
+{
+    if ( ! mbIsDisposed)
+    {
+        OSL_ASSERT(mbIsDisposed);
+        Dispose();
+    }
+}
+
+void SlideSorterView::Init()
+{
+    HandleModelChange();
+}
+
+void SlideSorterView::Dispose()
+{
+    mpLayeredDevice->Dispose();
+    mpPreviewCache.reset();
+
+    SetPageUnderMouse(SharedPageDescriptor());
+
+    // Hide the page to avoid problems in the view when deleting
+    // visualized objects
+    HideSdrPage();
+
+    // Deletion of the objects and the page will be done in SdrModel
+    // destructor (as long as objects and pages are added)
+
+    OSL_ASSERT(mpLayeredDevice.use_count() == 1);
+    mpLayeredDevice.reset();
+
+    mbIsDisposed = true;
+}
+
+sal_Int32 SlideSorterView::GetPageIndexAtPoint (const Point& rWindowPosition) const
+{
+    sal_Int32 nIndex (-1);
+
+    sd::Window *pWindow (mrSlideSorter.GetContentWindow().get());
+    if (pWindow)
+    {
+        nIndex = mpLayouter->GetIndexAtPoint(pWindow->PixelToLogic(rWindowPosition), false, false);
+
+        // Clip the page index against the page count.
+        if (nIndex >= mrModel.GetPageCount())
+            nIndex = -1;
+    }
+
+    return nIndex;
+}
+
+Layouter& SlideSorterView::GetLayouter() { return *mpLayouter; }
+
+void SlideSorterView::ModelHasChanged()
+{
+    // Ignore this call.  Rely on hints sent by the model to get informed of
+    // model changes.
+}
+
+void SlideSorterView::PreModelChange()
+{
+    // Reset the slide under the mouse.  It will be re-set in PostModelChange().
+    SetPageUnderMouse(SharedPageDescriptor());
+}
+
+void SlideSorterView::PostModelChange()
+{
+    // In PreModelChange() the page objects have been released.  Here we
+    // create new ones.
+    ::osl::MutexGuard aGuard (mrModel.GetMutex());
+
+    model::PageEnumerationProvider::CreateAllPagesEnumeration(mrModel);
+
+    // The new page objects have to be scaled and positioned.
+    RequestRearrange();
+    RequestRepaint();
+}
+
+/** At the moment for every model change all page objects are destroyed and
+    re-created again.  This can be optimized by accepting hints that
+    describe the type of change so that existing page objects can be
+    reused.
+*/
+void SlideSorterView::HandleModelChange()
+{
+    PreModelChange ();
+    PostModelChange();
+}
+
+void SlideSorterView::HandleDrawModeChange()
+{
+    // Replace the preview cache with a new and empty one.  The
+    // PreviewRenderer that is used by the cache is replaced by this as
+    // well.
+    mpPreviewCache.reset();
+    GetPreviewCache()->InvalidateCache();
+
+    RequestRepaint();
+}
+
+void SlideSorterView::HandleDataChangeEvent()
+{
+    GetPageObjectPainter()->SetTheme(mrSlideSorter.GetTheme());
+
+    // Update the color used by the background painter.
+    std::shared_ptr<BackgroundPainter> pPainter (
+        std::dynamic_pointer_cast<BackgroundPainter>(mpBackgroundPainter));
+    if (pPainter)
+        pPainter->SetColor(mrSlideSorter.GetTheme()->GetColor(Theme::Color_Background));
+
+    RequestRepaint();
+}
+
+void SlideSorterView::Resize()
+{
+    UpdateOrientation();
+
+    mpLayeredDevice->Resize();
+    RequestRearrange();
+}
+
+void SlideSorterView::RequestRearrange()
+{
+    mbIsRearrangePending = true;
+    Rearrange();
+}
+
+void SlideSorterView::Rearrange()
+{
+    if ( ! mbIsRearrangePending)
+        return;
+    if (mrModel.GetPageCount() <= 0)
+        return;
+
+    sd::Window *pWindow (mrSlideSorter.GetContentWindow().get());
+    if ( ! pWindow)
+        return;
+    const Size aWindowSize (pWindow->GetSizePixel());
+    if (aWindowSize.IsEmpty())
+        return;
+
+    const bool bRearrangeSuccess (
+        mpLayouter->Rearrange (
+            meOrientation,
+            aWindowSize,
+            mrModel.GetPageDescriptor(0)->GetPage()->GetSize(),
+            mrModel.GetPageCount()));
+    if (bRearrangeSuccess)
+    {
+        mbIsRearrangePending = false;
+        Layout();
+        UpdatePageUnderMouse();
+        //        RequestRepaint();
+    }
+}
+
+void SlideSorterView::UpdateOrientation()
+{
+    // The layout of slides depends on whether the slide sorter is
+    // displayed in the center or the side pane.
+    if (mrSlideSorter.GetViewShell()->IsMainViewShell())
+        SetOrientation(Layouter::GRID);
+    else
+    {
+        // Get access to the docking window.
+        vcl::Window* pWindow = mrSlideSorter.GetContentWindow();
+        PaneDockingWindow* pDockingWindow = nullptr;
+        while (pWindow!=nullptr && pDockingWindow==nullptr)
+        {
+            pDockingWindow = dynamic_cast<PaneDockingWindow*>(pWindow);
+            pWindow = pWindow->GetParent();
+        }
+
+        if (pDockingWindow != nullptr)
+        {
+            const ::tools::Long nScrollBarSize (
+                Application::GetSettings().GetStyleSettings().GetScrollBarSize());
+            switch (pDockingWindow->GetOrientation())
+            {
+                case PaneDockingWindow::HorizontalOrientation:
+                    if (SetOrientation(Layouter::HORIZONTAL))
+                    {
+                        const Range aRange (mpLayouter->GetValidVerticalSizeRange());
+                        pDockingWindow->SetValidSizeRange(Range(
+                            aRange.Min() + nScrollBarSize,
+                            aRange.Max() + nScrollBarSize));
+                    }
+                    break;
+
+                case PaneDockingWindow::VerticalOrientation:
+                    if (SetOrientation(Layouter::VERTICAL))
+                    {
+                        const Range aRange (mpLayouter->GetValidHorizontalSizeRange());
+                        pDockingWindow->SetValidSizeRange(Range(
+                            aRange.Min() + nScrollBarSize,
+                            aRange.Max() + nScrollBarSize));
+                    }
+                    break;
+
+                case PaneDockingWindow::UnknownOrientation:
+                    if (SetOrientation(Layouter::GRID))
+                    {
+                        const sal_Int32 nAdditionalSize (10);
+                        pDockingWindow->SetMinOutputSizePixel(Size(
+                            mpLayouter->GetValidHorizontalSizeRange().Min()
+                                + nScrollBarSize
+                                + nAdditionalSize,
+                            mpLayouter->GetValidVerticalSizeRange().Min()
+                                + nScrollBarSize
+                                + nAdditionalSize));
+                    }
+                    return;
+            }
+        }
+        else
+        {
+            // We are not placed in a docking window.  One possible reason
+            // is that the slide sorter is temporarily into a cache and was
+            // reparented to a non-docking window.
+            SetOrientation(Layouter::GRID);
+        }
+    }
+}
+
+void SlideSorterView::Layout ()
+{
+    sd::Window *pWindow (mrSlideSorter.GetContentWindow().get());
+    if (pWindow)
+    {
+        // Set the model area, i.e. the smallest rectangle that includes all
+        // page objects.
+        const ::tools::Rectangle aViewBox (mpLayouter->GetTotalBoundingBox());
+        pWindow->SetViewOrigin (aViewBox.TopLeft());
+        pWindow->SetViewSize (aViewBox.GetSize());
+
+        std::shared_ptr<PageObjectLayouter> pPageObjectLayouter(
+            mpLayouter->GetPageObjectLayouter());
+        if (pPageObjectLayouter)
+        {
+            const Size aNewPreviewSize (mpLayouter->GetPageObjectLayouter()->GetPreviewSize());
+            if (maPreviewSize != aNewPreviewSize && GetPreviewCache())
+            {
+                mpPreviewCache->ChangeSize(aNewPreviewSize, Bitmap::HasFastScale());
+                maPreviewSize = aNewPreviewSize;
+            }
+        }
+
+        // Iterate over all page objects and place them relative to the
+        // containing page.
+        model::PageEnumeration aPageEnumeration (
+            model::PageEnumerationProvider::CreateAllPagesEnumeration(mrModel));
+        while (aPageEnumeration.HasMoreElements())
+        {
+            model::SharedPageDescriptor pDescriptor (aPageEnumeration.GetNextElement());
+            pDescriptor->SetBoundingBox(mpLayouter->GetPageObjectBox(pDescriptor->GetPageIndex(), false));
+        }
+    }
+
+    InvalidatePageObjectVisibilities ();
+}
+
+void SlideSorterView::InvalidatePageObjectVisibilities()
+{
+    mbPageObjectVisibilitiesValid = false;
+}
+
+void SlideSorterView::DeterminePageObjectVisibilities()
+{
+    sd::Window *pWindow (mrSlideSorter.GetContentWindow().get());
+    if (!pWindow)
+        return;
+
+    // Set this flag to true here so that an invalidate during the
+    // visibility calculation can correctly invalidate it again.
+    mbPageObjectVisibilitiesValid = true;
+
+    ::tools::Rectangle aViewArea (pWindow->PixelToLogic(::tools::Rectangle(Point(0,0),pWindow->GetSizePixel())));
+    const Range aRange (mpLayouter->GetRangeOfVisiblePageObjects(aViewArea));
+    const Range aUnion(
+        ::std::min(maVisiblePageRange.Min(), aRange.Min()),
+        ::std::max(maVisiblePageRange.Max(), aRange.Max()));
+
+    // For page objects that just dropped off the visible area we
+    // decrease the priority of pending requests for preview bitmaps.
+    if (maVisiblePageRange != aRange)
+        mbPreciousFlagUpdatePending |= true;
+
+    model::SharedPageDescriptor pDescriptor;
+    for (::tools::Long nIndex=aUnion.Min(); nIndex<=aUnion.Max(); nIndex++)
+    {
+        pDescriptor = mrModel.GetPageDescriptor(nIndex);
+        if (pDescriptor)
+            SetState(
+                pDescriptor,
+                PageDescriptor::ST_Visible,
+                aRange.Contains(nIndex));
+    }
+
+    // Broadcast a change of the set of visible page objects.
+    if (maVisiblePageRange != aRange)
+    {
+        maVisiblePageRange = aRange;
+
+        // Tell the listeners that the visibility of some objects has
+        // changed.
+        ::std::vector<Link<LinkParamNone*,void>>& aChangeListeners (maVisibilityChangeListeners);
+        for (const auto& rLink : aChangeListeners)
+        {
+            rLink.Call(nullptr);
+        }
+    }
+
+    // Restore the mouse over state.
+    UpdatePageUnderMouse();
+}
+
+void SlideSorterView::UpdatePreciousFlags()
+{
+    if (!mbPreciousFlagUpdatePending)
+        return;
+
+    mbPreciousFlagUpdatePending = false;
+
+    model::SharedPageDescriptor pDescriptor;
+    std::shared_ptr<cache::PageCache> pCache = GetPreviewCache();
+    sal_Int32 nPageCount (mrModel.GetPageCount());
+
+    for (int nIndex=0; nIndex<=nPageCount; ++nIndex)
+    {
+        pDescriptor = mrModel.GetPageDescriptor(nIndex);
+        if (pDescriptor)
+        {
+            pCache->SetPreciousFlag(
+                pDescriptor->GetPage(),
+                maVisiblePageRange.Contains(nIndex));
+        }
+        else
+        {
+            // At least one cache entry can not be updated.  Remember to
+            // repeat the whole updating later and leave the loop now.
+            mbPreciousFlagUpdatePending = true;
+            break;
+        }
+    }
+}
+
+bool SlideSorterView::SetOrientation (const Layouter::Orientation eOrientation)
+{
+    if (meOrientation != eOrientation)
+    {
+        meOrientation = eOrientation;
+        return true;
+    }
+    else
+        return false;
+}
+
+void SlideSorterView::RequestRepaint()
+{
+    sd::Window *pWindow (mrSlideSorter.GetContentWindow().get());
+    if (pWindow)
+    {
+        mpLayeredDevice->InvalidateAllLayers(
+            ::tools::Rectangle(
+                pWindow->PixelToLogic(Point(0,0)),
+                pWindow->PixelToLogic(pWindow->GetSizePixel())));
+        pWindow->Invalidate();
+    }
+}
+
+void SlideSorterView::RequestRepaint (const model::SharedPageDescriptor& rpDescriptor)
+{
+    if (rpDescriptor)
+        RequestRepaint(rpDescriptor->GetBoundingBox());
+}
+
+void SlideSorterView::RequestRepaint (const ::tools::Rectangle& rRepaintBox)
+{
+    sd::Window *pWindow (mrSlideSorter.GetContentWindow().get());
+    if (pWindow)
+    {
+        mpLayeredDevice->InvalidateAllLayers(rRepaintBox);
+        pWindow->Invalidate(rRepaintBox);
+    }
+}
+
+void SlideSorterView::RequestRepaint (const vcl::Region& rRepaintRegion)
+{
+    sd::Window *pWindow (mrSlideSorter.GetContentWindow().get());
+    if (pWindow)
+    {
+        mpLayeredDevice->InvalidateAllLayers(rRepaintRegion);
+        pWindow->Invalidate(rRepaintRegion);
+    }
+}
+
+::tools::Rectangle SlideSorterView::GetModelArea() const
+{
+    return mpLayouter->GetTotalBoundingBox();
+}
+
+#ifdef DEBUG_TIMING
+static ::canvas::tools::ElapsedTime gaTimer;
+static const size_t gFrameTimeCount (10);
+static size_t gFrameTimeIndex (0);
+static ::std::vector<double> gFrameTimes (gFrameTimeCount, 0);
+static double gFrameTimeSum (0);
+static const ::tools::Rectangle gFrameTimeBox (10,10,150,20);
+static double gnLastFrameStart = 0;
+#endif
+
+void SlideSorterView::CompleteRedraw (
+    OutputDevice* pDevice,
+    const vcl::Region& rPaintArea,
+    sdr::contact::ViewObjectContactRedirector* pRedirector)
+{
+    (void)pRedirector;
+
+    if (comphelper::LibreOfficeKit::isActive())
+        return;
+
+    if (pDevice == nullptr || pDevice!=mrSlideSorter.GetContentWindow()->GetOutDev())
+        return;
+
+#ifdef DEBUG_TIMING
+    const double nStartTime (gaTimer.getElapsedTime());
+    SAL_INFO("sd.timing", "SlideSorterView::CompleteRedraw start" << (mnLockRedrawSmph ? " locked" : ""));
+#endif
+
+    // The parent implementation of CompleteRedraw is called only when
+    // painting is locked.  We do all the painting ourself.  When painting
+    // is locked the parent implementation keeps track of the repaint
+    // requests and later, when painting is unlocked, calls CompleteRedraw
+    // for all missed repaints.
+
+    if (mnLockRedrawSmph == 0)
+    {
+        if (mpLayeredDevice->HandleMapModeChange())
+            DeterminePageObjectVisibilities();
+        mpLayeredDevice->Repaint(rPaintArea);
+    }
+    else
+    {
+        maRedrawRegion.Union(rPaintArea);
+    }
+
+#ifdef DEBUG_TIMING
+    const double nEndTime (gaTimer.getElapsedTime());
+    SAL_INFO("sd.timing", "SlideSorterView::CompleteRedraw end after " << (nEndTime-nStartTime)*1000 << " ms");
+    gFrameTimeSum -= gFrameTimes[gFrameTimeIndex];
+    gFrameTimes[gFrameTimeIndex] = nStartTime - gnLastFrameStart;
+    gnLastFrameStart = nStartTime;
+    gFrameTimeSum += gFrameTimes[gFrameTimeIndex];
+    gFrameTimeIndex = (gFrameTimeIndex+1) % gFrameTimeCount;
+
+    mrSlideSorter.GetContentWindow()->SetFillColor(COL_BLUE);
+    mrSlideSorter.GetContentWindow()->DrawRect(gFrameTimeBox);
+    mrSlideSorter.GetContentWindow()->SetTextColor(COL_WHITE);
+    mrSlideSorter.GetContentWindow()->DrawText(
+        gFrameTimeBox,
+        OUString::number(1 / (gFrameTimeSum / gFrameTimeCount)),
+        DrawTextFlags::Right | DrawTextFlags::VCenter);
+    //    mrSlideSorter.GetContentWindow()->Invalidate(gFrameTimeBox);
+#endif
+}
+
+void SlideSorterView::Paint (
+    OutputDevice& rDevice,
+    const ::tools::Rectangle& rRepaintArea)
+{
+    if (rRepaintArea.IsEmpty())
+        return;
+
+    if ( ! mpPageObjectPainter)
+        if ( ! GetPageObjectPainter())
+            return;
+
+    // Update the page visibilities when they have been invalidated.
+    if ( ! mbPageObjectVisibilitiesValid)
+        DeterminePageObjectVisibilities();
+
+    if (mbPreciousFlagUpdatePending)
+        UpdatePreciousFlags();
+
+    if (mbIsRearrangePending)
+        Rearrange();
+
+    // Paint all page objects that are fully or partially inside the
+    // repaint region.
+    const Range aRange (mpLayouter->GetRangeOfVisiblePageObjects(rRepaintArea));
+    // Try to prefetch all graphics from the pages to paint. This will be done
+    // in threads to be more efficient than loading them on-demand one by one.
+    std::vector<Graphic*> graphics;
+    for (::tools::Long nIndex=aRange.Min(); nIndex<=aRange.Max(); ++nIndex)
+    {
+        model::SharedPageDescriptor pDescriptor (mrModel.GetPageDescriptor(nIndex));
+        if (!pDescriptor || ! pDescriptor->HasState(PageDescriptor::ST_Visible))
+            continue;
+        pDescriptor->GetPage()->getGraphicsForPrefetch(graphics);
+    }
+    // Handle also one page before and after to have those in advance on scrolling.
+    for (::tools::Long nIndex : { aRange.Min() - 1, aRange.Max() + 1 })
+    {
+        model::SharedPageDescriptor pDescriptor (mrModel.GetPageDescriptor(nIndex));
+        if (!pDescriptor)
+            continue;
+        pDescriptor->GetPage()->getGraphicsForPrefetch(graphics);
+    }
+    if(graphics.size() > 1) // threading does not help with loading just one
+        GraphicFilter::GetGraphicFilter().MakeGraphicsAvailableThreaded(graphics);
+
+    for (::tools::Long nIndex=aRange.Min(); nIndex<=aRange.Max(); ++nIndex)
+    {
+        model::SharedPageDescriptor pDescriptor (mrModel.GetPageDescriptor(nIndex));
+        if (!pDescriptor || ! pDescriptor->HasState(PageDescriptor::ST_Visible))
+            continue;
+
+        mpPageObjectPainter->PaintPageObject(rDevice, pDescriptor);
+    }
+}
+
+void SlideSorterView::ConfigurationChanged (
+    utl::ConfigurationBroadcaster* pBroadcaster,
+    ConfigurationHints nHint)
+{
+    // Some changes of the configuration (some of the colors for example)
+    // may affect the previews.  Throw away the old ones and create new ones.
+    cache::PageCacheManager::Instance()->InvalidateAllCaches();
+
+    ::sd::View::ConfigurationChanged(pBroadcaster, nHint);
+    RequestRepaint();
+
+}
+
+std::shared_ptr<cache::PageCache> const & SlideSorterView::GetPreviewCache()
+{
+    sd::Window *pWindow (mrSlideSorter.GetContentWindow().get());
+    if (pWindow && mpPreviewCache == nullptr)
+    {
+        mpPreviewCache =
+            std::make_shared<cache::PageCache>(
+                mpLayouter->GetPageObjectSize(),
+                Bitmap::HasFastScale(),
+                std::make_shared<ViewCacheContext>(mrSlideSorter));
+    }
+
+    return mpPreviewCache;
+}
+
+Range const & SlideSorterView::GetVisiblePageRange()
+{
+    if ( ! mbPageObjectVisibilitiesValid)
+        DeterminePageObjectVisibilities();
+    return maVisiblePageRange;
+}
+
+void SlideSorterView::AddVisibilityChangeListener (const Link<LinkParamNone*,void>& rListener)
+{
+    if (::std::find (
+        maVisibilityChangeListeners.begin(),
+        maVisibilityChangeListeners.end(),
+        rListener) == maVisibilityChangeListeners.end())
+    {
+        maVisibilityChangeListeners.push_back(rListener);
+    }
+}
+
+void SlideSorterView::RemoveVisibilityChangeListener(const Link<LinkParamNone*,void>&rListener)
+{
+    maVisibilityChangeListeners.erase (
+        ::std::find (
+            maVisibilityChangeListeners.begin(),
+            maVisibilityChangeListeners.end(),
+            rListener));
+}
+
+ToolTip& SlideSorterView::GetToolTip() const
+{
+    OSL_ASSERT(mpToolTip);
+    return *mpToolTip;
+}
+
+void SlideSorterView::DragFinished (sal_Int8 nDropAction)
+{
+    mrSlideSorter.GetController().GetClipboard().DragFinished(nDropAction);
+
+    View::DragFinished(nDropAction);
+}
+
+void SlideSorterView::UpdatePageUnderMouse ()
+{
+    VclPtr<ScrollBar> pVScrollBar (mrSlideSorter.GetVerticalScrollBar());
+    VclPtr<ScrollBar> pHScrollBar (mrSlideSorter.GetHorizontalScrollBar());
+    if ((pVScrollBar && pVScrollBar->IsVisible() && pVScrollBar->IsTracking())
+        || (pHScrollBar && pHScrollBar->IsVisible() && pHScrollBar->IsTracking()))
+    {
+        // One of the scroll bars is tracking mouse movement.  Do not
+        // highlight the slide under the mouse in this case.
+        SetPageUnderMouse(SharedPageDescriptor());
+        return;
+    }
+
+    sd::Window *pWindow (mrSlideSorter.GetContentWindow().get());
+    if (pWindow && pWindow->IsVisible() && ! pWindow->IsMouseCaptured())
+    {
+        const Window::PointerState aPointerState (pWindow->GetPointerState());
+        const ::tools::Rectangle aWindowBox (pWindow->GetPosPixel(), pWindow->GetSizePixel());
+        if (aWindowBox.Contains(aPointerState.maPos))
+        {
+            UpdatePageUnderMouse(aPointerState.maPos);
+            return;
+        }
+    }
+
+    SetPageUnderMouse(SharedPageDescriptor());
+}
+
+void SlideSorterView::UpdatePageUnderMouse (
+    const Point& rMousePosition)
+{
+    SetPageUnderMouse(mrSlideSorter.GetController().GetPageAt(rMousePosition));
+}
+
+void SlideSorterView::SetPageUnderMouse (
+    const model::SharedPageDescriptor& rpDescriptor)
+{
+    if (mpPageUnderMouse == rpDescriptor)
+        return;
+
+    if (mpPageUnderMouse)
+        SetState(mpPageUnderMouse, PageDescriptor::ST_MouseOver, false);
+
+    mpPageUnderMouse = rpDescriptor;
+
+    if (mpPageUnderMouse)
+        SetState(mpPageUnderMouse, PageDescriptor::ST_MouseOver, true);
+
+    // Change the quick help text to display the name of the page under
+    // the mouse.
+    mpToolTip->SetPage(rpDescriptor);
+}
+
+bool SlideSorterView::SetState (
+    const model::SharedPageDescriptor& rpDescriptor,
+    const PageDescriptor::State eState,
+    const bool bStateValue)
+{
+    if ( ! rpDescriptor)
+        return false;
+
+    const bool bModified (rpDescriptor->SetState(eState, bStateValue));
+    if ( ! bModified)
+        return false;
+
+    // When the page object is not visible (i.e. not on the screen then
+    // nothing has to be painted.
+    if (rpDescriptor->HasState(PageDescriptor::ST_Visible))
+    {
+        // For most states a change of that state leads to visible
+        // difference and we have to request a repaint.
+        if (eState != PageDescriptor::ST_WasSelected)
+            RequestRepaint(rpDescriptor);
+    }
+
+    return bModified;
+}
+
+std::shared_ptr<PageObjectPainter> const & SlideSorterView::GetPageObjectPainter()
+{
+    if ( ! mpPageObjectPainter)
+        mpPageObjectPainter = std::make_shared<PageObjectPainter>(mrSlideSorter);
+    return mpPageObjectPainter;
+}
+
+//===== SlideSorterView::DrawLock =============================================
+
+SlideSorterView::DrawLock::DrawLock (SlideSorter const & rSlideSorter)
+    : mrView(rSlideSorter.GetView()),
+      mpWindow(rSlideSorter.GetContentWindow())
+{
+    if (mrView.mnLockRedrawSmph == 0)
+        mrView.maRedrawRegion.SetEmpty();
+    ++mrView.mnLockRedrawSmph;
+}
+
+SlideSorterView::DrawLock::~DrawLock()
+{
+    OSL_ASSERT(mrView.mnLockRedrawSmph>0);
+    --mrView.mnLockRedrawSmph;
+    if (mrView.mnLockRedrawSmph == 0)
+        if (mpWindow)
+        {
+            mpWindow->Invalidate(mrView.maRedrawRegion);
+        }
+}
+
+void SlideSorterView::DrawLock::Dispose()
+{
+    mpWindow.reset();
+}
+
+} // end of namespace ::sd::slidesorter::view
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/view/SlsFramePainter.cxx b/sd/source/ui/slidesorter/view/SlsFramePainter.cxx
new file mode 100644
index 000000000..31c301868
--- /dev/null
+++ b/sd/source/ui/slidesorter/view/SlsFramePainter.cxx
@@ -0,0 +1,225 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "SlsFramePainter.hxx"
+#include <vcl/outdev.hxx>
+#include <osl/diagnose.h>
+
+namespace sd::slidesorter::view {
+
+FramePainter::FramePainter (const BitmapEx& rShadowBitmap)
+    : maTopLeft(rShadowBitmap,-1,-1),
+      maTop(rShadowBitmap,0,-1),
+      maTopRight(rShadowBitmap,+1,-1),
+      maLeft(rShadowBitmap,-1,0),
+      maRight(rShadowBitmap,+1,0),
+      maBottomLeft(rShadowBitmap,-1,+1),
+      maBottom(rShadowBitmap,0,+1),
+      maBottomRight(rShadowBitmap,+1,+1),
+      maCenter(rShadowBitmap,0,0),
+      mbIsValid(false)
+{
+    if (rShadowBitmap.GetSizePixel().Width() == rShadowBitmap.GetSizePixel().Height()
+        && (rShadowBitmap.GetSizePixel().Width()-1)%2 == 0
+        && ((rShadowBitmap.GetSizePixel().Width()-1)/2)%2 == 1)
+    {
+        mbIsValid = true;
+    }
+    else
+    {
+        OSL_ASSERT(rShadowBitmap.GetSizePixel().Width() == rShadowBitmap.GetSizePixel().Height());
+        OSL_ASSERT((rShadowBitmap.GetSizePixel().Width()-1)%2 == 0);
+        OSL_ASSERT(((rShadowBitmap.GetSizePixel().Width()-1)/2)%2 == 1);
+    }
+}
+
+FramePainter::~FramePainter()
+{
+}
+
+void FramePainter::PaintFrame (
+    OutputDevice& rDevice,
+    const ::tools::Rectangle& rBox) const
+{
+    if ( ! mbIsValid)
+        return;
+
+    // Paint the shadow.
+    maTopLeft.PaintCorner(rDevice, rBox.TopLeft());
+    maTopRight.PaintCorner(rDevice, rBox.TopRight());
+    maBottomLeft.PaintCorner(rDevice, rBox.BottomLeft());
+    maBottomRight.PaintCorner(rDevice, rBox.BottomRight());
+    maLeft.PaintSide(rDevice, rBox.TopLeft(), rBox.BottomLeft(), maTopLeft, maBottomLeft);
+    maRight.PaintSide(rDevice, rBox.TopRight(), rBox.BottomRight(), maTopRight, maBottomRight);
+    maTop.PaintSide(rDevice, rBox.TopLeft(), rBox.TopRight(), maTopLeft, maTopRight);
+    maBottom.PaintSide(rDevice, rBox.BottomLeft(), rBox.BottomRight(), maBottomLeft, maBottomRight);
+    maCenter.PaintCenter(rDevice,rBox);
+}
+
+void FramePainter::AdaptColor (
+    const Color aNewColor)
+{
+    // Get the source color.
+    if (maCenter.maBitmap.IsEmpty())
+        return;
+    const Color aSourceColor = maCenter.maBitmap.GetPixelColor(0,0);
+
+    // Erase the center bitmap.
+    maCenter.maBitmap.SetEmpty();
+
+    // Replace the color in all bitmaps.
+    maTopLeft.maBitmap.Replace(aSourceColor, aNewColor);
+    maTop.maBitmap.Replace(aSourceColor, aNewColor);
+    maTopRight.maBitmap.Replace(aSourceColor, aNewColor);
+    maLeft.maBitmap.Replace(aSourceColor, aNewColor);
+    maCenter.maBitmap.Replace(aSourceColor, aNewColor);
+    maRight.maBitmap.Replace(aSourceColor, aNewColor);
+    maBottomLeft.maBitmap.Replace(aSourceColor, aNewColor);
+    maBottom.maBitmap.Replace(aSourceColor, aNewColor);
+    maBottomRight.maBitmap.Replace(aSourceColor, aNewColor);
+}
+
+//===== FramePainter::OffsetBitmap ============================================
+
+FramePainter::OffsetBitmap::OffsetBitmap (
+    const BitmapEx& rBitmap,
+    const sal_Int32 nHorizontalPosition,
+    const sal_Int32 nVerticalPosition)
+{
+    OSL_ASSERT(nHorizontalPosition>=-1 && nHorizontalPosition<=+1);
+    OSL_ASSERT(nVerticalPosition>=-1 && nVerticalPosition<=+1);
+
+    const sal_Int32 nS (1);
+    const sal_Int32 nC (::std::max<sal_Int32>(0,(rBitmap.GetSizePixel().Width()-nS)/2));
+    const sal_Int32 nO (nC/2);
+
+    const Point aOrigin(
+        nHorizontalPosition<0 ? 0 : (nHorizontalPosition == 0 ? nC : nC+nS),
+        nVerticalPosition<0 ? 0 : (nVerticalPosition == 0 ? nC : nC+nS));
+    const Size aSize(
+        nHorizontalPosition==0 ? nS : nC,
+        nVerticalPosition==0 ? nS : nC);
+    maBitmap = BitmapEx(rBitmap, aOrigin, aSize);
+    if (maBitmap.IsEmpty())
+        return;
+    maOffset = Point(
+        nHorizontalPosition<0 ? -nO : nHorizontalPosition>0 ? -nO : 0,
+        nVerticalPosition<0 ? -nO : nVerticalPosition>0 ? -nO : 0);
+
+    // Enlarge the side bitmaps so that painting the frame requires less
+    // paint calls.
+    const sal_Int32 nSideBitmapSize (64);
+    if (nHorizontalPosition == 0 && nVerticalPosition == 0)
+    {
+        maBitmap.Scale(Size(nSideBitmapSize,nSideBitmapSize));
+    }
+    else if (nHorizontalPosition == 0)
+    {
+        maBitmap.Scale(Size(nSideBitmapSize,aSize.Height()));
+    }
+    else if (nVerticalPosition == 0)
+    {
+        maBitmap.Scale(Size(maBitmap.GetSizePixel().Width(), nSideBitmapSize));
+    }
+}
+
+void FramePainter::OffsetBitmap::PaintCorner (
+    OutputDevice& rDevice,
+    const Point& rAnchor) const
+{
+    if ( ! maBitmap.IsEmpty())
+        rDevice.DrawBitmapEx(rAnchor+maOffset, maBitmap);
+}
+
+void FramePainter::OffsetBitmap::PaintSide (
+    OutputDevice& rDevice,
+    const Point& rAnchor1,
+    const Point& rAnchor2,
+    const OffsetBitmap& rCornerBitmap1,
+    const OffsetBitmap& rCornerBitmap2) const
+{
+    if (maBitmap.IsEmpty())
+        return;
+
+    const Size aBitmapSize (maBitmap.GetSizePixel());
+    if (rAnchor1.Y() == rAnchor2.Y())
+    {
+        // Side is horizontal.
+        const sal_Int32 nY (rAnchor1.Y() + maOffset.Y());
+        const sal_Int32 nLeft (
+            rAnchor1.X()
+            + rCornerBitmap1.maBitmap.GetSizePixel().Width()
+            + rCornerBitmap1.maOffset.X());
+        const sal_Int32 nRight (
+            rAnchor2.X()
+            + rCornerBitmap2.maOffset.X()
+            - 1);
+        for (sal_Int32 nX=nLeft; nX<=nRight; nX+=aBitmapSize.Width())
+        {
+            rDevice.DrawBitmapEx(
+                Point(nX,nY),
+                Size(std::min(aBitmapSize.Width(),static_cast<::tools::Long>(nRight-nX+1)),aBitmapSize.Height()),
+                maBitmap);
+        }
+    }
+    else if (rAnchor1.X() == rAnchor2.X())
+    {
+        // Side is vertical.
+        const sal_Int32 nX (rAnchor1.X() + maOffset.X());
+        const sal_Int32 nTop (
+            rAnchor1.Y()
+            + rCornerBitmap1.maBitmap.GetSizePixel().Height()
+            + rCornerBitmap1.maOffset.Y());
+        const sal_Int32 nBottom (
+            rAnchor2.Y()
+            + rCornerBitmap2.maOffset.Y()
+            - 1);
+        for (sal_Int32 nY=nTop; nY<=nBottom; nY+=aBitmapSize.Height())
+        {
+            rDevice.DrawBitmapEx(
+                Point(nX,nY),
+                Size(aBitmapSize.Width(), std::min(aBitmapSize.Height(), static_cast<::tools::Long>(nBottom-nY+1))),
+                maBitmap);
+        }
+    }
+    else
+    {
+        // Diagonal sides indicates an error.
+        OSL_ASSERT(false);
+    }
+}
+
+void FramePainter::OffsetBitmap::PaintCenter (
+    OutputDevice& rDevice,
+    const ::tools::Rectangle& rBox) const
+{
+    const Size aBitmapSize (maBitmap.GetSizePixel());
+    for (::tools::Long nY=rBox.Top(); nY<=rBox.Bottom(); nY+=aBitmapSize.Height())
+        for (::tools::Long nX=rBox.Left(); nX<=rBox.Right(); nX+=aBitmapSize.Width())
+            rDevice.DrawBitmapEx(
+                Point(nX,nY),
+                Size(
+                    ::std::min(aBitmapSize.Width(), rBox.Right()-nX+1),
+                    std::min(aBitmapSize.Height(), rBox.Bottom()-nY+1)),
+                maBitmap);
+}
+
+} // end of namespace sd::slidesorter::view
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/view/SlsFramePainter.hxx b/sd/source/ui/slidesorter/view/SlsFramePainter.hxx
new file mode 100644
index 000000000..9398cb94e
--- /dev/null
+++ b/sd/source/ui/slidesorter/view/SlsFramePainter.hxx
@@ -0,0 +1,109 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <vcl/bitmapex.hxx>
+
+namespace sd::slidesorter::view {
+
+class FramePainter
+{
+public:
+    explicit FramePainter (const BitmapEx& rBitmap);
+    ~FramePainter();
+
+    /** Paint a border around the given box by using a set of bitmaps for
+        the corners and sides.
+    */
+    void PaintFrame (OutputDevice&rDevice, const ::tools::Rectangle& rBox) const;
+
+    /** Special functionality that takes the color from the center
+        bitmap and replaces that color in all bitmaps by the given new
+        color.  Alpha values are not modified.
+        The center bitmap is erased.
+    */
+    void AdaptColor (const Color aNewColor);
+
+private:
+    /** Bitmap with offset that is used when the bitmap is painted.  The bitmap
+    */
+    class OffsetBitmap {
+    public:
+        BitmapEx maBitmap;
+        Point maOffset;
+
+        /** Create one of the eight shadow bitmaps from one that combines
+            them all.  This larger bitmap is expected to have dimension NxN
+            with N=1+2*M.  Of this larger bitmap there are created four
+            corner bitmaps of size 2*M x 2*M and four side bitmaps of sizes
+            1xM (top and bottom) and Mx1 (left and right).  The corner
+            bitmaps have each one quadrant of size MxM that is painted under
+            the interior of the frame.
+            @param rBitmap
+                The larger bitmap of which the eight shadow bitmaps are cut
+                out from.
+            @param nHorizontalPosition
+                Valid values are -1 (left), 0 (center), and +1 (right).
+            @param nVerticalPosition
+                Valid values are -1 (top), 0 (center), and +1 (bottom).
+        */
+        OffsetBitmap (
+            const BitmapEx& rBitmap,
+            const sal_Int32 nHorizontalPosition,
+            const sal_Int32 nVerticalPosition);
+
+        /** Use the given device to paint the bitmap at the location that is
+            the sum of the given anchor and the internal offset.
+        */
+        void PaintCorner (OutputDevice& rDevice, const Point& rAnchor) const;
+
+        /** Use the given device to paint the bitmap stretched between the
+            two given locations.  Offsets of the adjacent corner bitmaps and
+            the offset of the side bitmap are used to determine the area
+            that is to be filled with the side bitmap.
+        */
+        void PaintSide (
+            OutputDevice& rDevice,
+            const Point& rAnchor1,
+            const Point& rAnchor2,
+            const OffsetBitmap& rCornerBitmap1,
+            const OffsetBitmap& rCornerBitmap2) const;
+
+        /** Fill the given rectangle with the bitmap.
+        */
+        void PaintCenter (
+            OutputDevice& rDevice,
+            const ::tools::Rectangle& rBox) const;
+    };
+    OffsetBitmap maTopLeft;
+    OffsetBitmap maTop;
+    OffsetBitmap maTopRight;
+    OffsetBitmap maLeft;
+    OffsetBitmap maRight;
+    OffsetBitmap maBottomLeft;
+    OffsetBitmap maBottom;
+    OffsetBitmap maBottomRight;
+    OffsetBitmap maCenter;
+    bool mbIsValid;
+};
+
+} // end of namespace sd::slidesorter::view
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/view/SlsInsertAnimator.cxx b/sd/source/ui/slidesorter/view/SlsInsertAnimator.cxx
new file mode 100644
index 000000000..361c55f05
--- /dev/null
+++ b/sd/source/ui/slidesorter/view/SlsInsertAnimator.cxx
@@ -0,0 +1,428 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <view/SlsInsertAnimator.hxx>
+#include <controller/SlideSorterController.hxx>
+#include <controller/SlsAnimationFunction.hxx>
+#include <view/SlideSorterView.hxx>
+#include <view/SlsLayouter.hxx>
+#include <model/SlideSorterModel.hxx>
+#include <SlideSorter.hxx>
+#include <Window.hxx>
+#include <osl/diagnose.h>
+
+#include <memory>
+#include <set>
+
+namespace sd::slidesorter::view {
+
+namespace {
+
+class PageObjectRun;
+
+class AnimatorAccess
+{
+public:
+    virtual void AddRun (const std::shared_ptr<PageObjectRun>& rRun) = 0;
+    virtual void RemoveRun (const std::shared_ptr<PageObjectRun>& rRun) = 0;
+    virtual model::SlideSorterModel& GetModel () const = 0;
+    virtual view::SlideSorterView& GetView () const = 0;
+    virtual std::shared_ptr<controller::Animator> GetAnimator () = 0;
+    virtual VclPtr<sd::Window> GetContentWindow () = 0;
+
+protected:
+    ~AnimatorAccess() COVERITY_NOEXCEPT_FALSE {}
+};
+
+/** Controller of the position offsets of all page objects in one row or one
+    column.
+*/
+class PageObjectRun : public std::enable_shared_from_this<PageObjectRun>
+{
+public:
+    PageObjectRun (
+        AnimatorAccess& rAnimatorAccess,
+        const sal_Int32 nRunIndex,
+        const sal_Int32 nStartIndex,
+        const sal_Int32 nEndIndex);
+
+    void operator () (const double nTime);
+
+    void UpdateOffsets(
+        const InsertPosition& rInsertPosition,
+        const view::Layouter& GetLayouter);
+    void ResetOffsets (const controller::Animator::AnimationMode eMode);
+
+    /// Index of the row or column that this run represents.
+    sal_Int32 mnRunIndex;
+    /// The index at which to make place for the insertion indicator (-1 for
+    /// no indicator).
+    sal_Int32 mnLocalInsertIndex;
+    /// Index of the first page in the run.
+    sal_Int32 mnStartIndex;
+    /// Index of the last page in the run.
+    sal_Int32 mnEndIndex;
+    /// Offset of each item in the run at the start of the current animation.
+    ::std::vector<Point> maStartOffset;
+    /// Target offset of each item in the run at the end of the current animation.
+    ::std::vector<Point> maEndOffset;
+    /// Time at which the current animation started.
+    double mnStartTime;
+
+    class Comparator
+    {
+        public: bool operator() (
+            const std::shared_ptr<PageObjectRun>& rpRunA,
+            const std::shared_ptr<PageObjectRun>& rpRunB) const
+        {
+            return rpRunA->mnRunIndex < rpRunB->mnRunIndex;
+        }
+    };
+private:
+    controller::Animator::AnimationId mnAnimationId;
+    AnimatorAccess& mrAnimatorAccess;
+    ::std::function<double (double)> maAccelerationFunction;
+
+    void RestartAnimation();
+};
+typedef std::shared_ptr<PageObjectRun> SharedPageObjectRun;
+
+Point Blend (const Point& rPointA, const Point& rPointB, const double nT)
+{
+    return Point(
+        sal_Int32(rPointA.X() * (1-nT) + rPointB.X() * nT),
+        sal_Int32(rPointA.Y() * (1-nT) + rPointB.Y() * nT));
+}
+
+} // end of anonymous namespace
+
+class InsertAnimator::Implementation : public AnimatorAccess
+{
+public:
+    explicit Implementation (SlideSorter& rSlideSorter);
+    virtual ~Implementation();
+
+    void SetInsertPosition (
+        const InsertPosition& rInsertPosition,
+        const controller::Animator::AnimationMode eAnimationMode);
+
+    virtual void AddRun (const std::shared_ptr<PageObjectRun>& rRun) override;
+    virtual void RemoveRun (const std::shared_ptr<PageObjectRun>& rRun) override;
+
+    virtual model::SlideSorterModel& GetModel() const override { return mrModel; }
+    virtual view::SlideSorterView& GetView() const override { return mrView; }
+    virtual std::shared_ptr<controller::Animator> GetAnimator() override { return mpAnimator; }
+    virtual VclPtr<sd::Window> GetContentWindow() override { return mrSlideSorter.GetContentWindow(); }
+
+private:
+    model::SlideSorterModel& mrModel;
+    view::SlideSorterView& mrView;
+    SlideSorter& mrSlideSorter;
+    std::shared_ptr<controller::Animator> mpAnimator;
+    typedef ::std::set<SharedPageObjectRun, PageObjectRun::Comparator> RunContainer;
+    RunContainer maRuns;
+    InsertPosition maInsertPosition;
+
+    SharedPageObjectRun GetRun (
+        view::Layouter const & rLayouter,
+        const InsertPosition& rInsertPosition);
+    RunContainer::const_iterator FindRun (const sal_Int32 nRunIndex) const;
+};
+
+//===== InsertAnimator ========================================================
+
+InsertAnimator::InsertAnimator (SlideSorter& rSlideSorter)
+    : mpImplementation(std::make_shared<Implementation>(rSlideSorter))
+{
+}
+
+void InsertAnimator::SetInsertPosition (const InsertPosition& rInsertPosition)
+{
+    mpImplementation->SetInsertPosition(rInsertPosition, controller::Animator::AM_Animated);
+}
+
+void InsertAnimator::Reset (const controller::Animator::AnimationMode eMode)
+{
+    mpImplementation->SetInsertPosition(InsertPosition(), eMode);
+}
+
+//===== InsertAnimator::Implementation ========================================
+
+InsertAnimator::Implementation::Implementation (SlideSorter& rSlideSorter)
+    : mrModel(rSlideSorter.GetModel()),
+      mrView(rSlideSorter.GetView()),
+      mrSlideSorter(rSlideSorter),
+      mpAnimator(rSlideSorter.GetController().GetAnimator())
+{
+}
+
+InsertAnimator::Implementation::~Implementation()
+{
+    SetInsertPosition(InsertPosition(), controller::Animator::AM_Immediate);
+}
+
+void InsertAnimator::Implementation::SetInsertPosition (
+    const InsertPosition& rInsertPosition,
+    const controller::Animator::AnimationMode eMode)
+{
+    if (maInsertPosition == rInsertPosition)
+        return;
+
+    SharedPageObjectRun pOldRun (GetRun(mrView.GetLayouter(), maInsertPosition));
+    SharedPageObjectRun pCurrentRun (GetRun(mrView.GetLayouter(), rInsertPosition));
+    maInsertPosition = rInsertPosition;
+
+    // When the new insert position is in a different run then move the page
+    // objects in the old run to their default positions.
+    if (pOldRun != pCurrentRun && pOldRun)
+        pOldRun->ResetOffsets(eMode);
+
+    if (pCurrentRun)
+    {
+        pCurrentRun->UpdateOffsets(rInsertPosition, mrView.GetLayouter());
+    }
+}
+
+SharedPageObjectRun InsertAnimator::Implementation::GetRun (
+    view::Layouter const & rLayouter,
+    const InsertPosition& rInsertPosition)
+{
+    const sal_Int32 nRow (rInsertPosition.GetRow());
+    if (nRow < 0)
+        return SharedPageObjectRun();
+
+    RunContainer::const_iterator iRun (maRuns.end());
+    if (rLayouter.GetColumnCount() == 1)
+    {
+        // There is only one run that contains all slides.
+        if (maRuns.empty())
+            maRuns.insert(std::make_shared<PageObjectRun>(
+                *this,
+                0,
+                0,
+                mrModel.GetPageCount()-1));
+        iRun = maRuns.begin();
+    }
+    else
+    {
+        iRun = FindRun(nRow);
+        if (iRun == maRuns.end())
+        {
+            // Create a new run.
+            const sal_Int32 nStartIndex (rLayouter.GetIndex(nRow, 0));
+            const sal_Int32 nEndIndex (rLayouter.GetIndex(nRow, rLayouter.GetColumnCount()-1));
+            if (nStartIndex <= nEndIndex)
+            {
+                iRun = maRuns.insert(std::make_shared<PageObjectRun>(
+                    *this,
+                    nRow,
+                    nStartIndex,
+                    nEndIndex)).first;
+                OSL_ASSERT(iRun != maRuns.end());
+            }
+        }
+    }
+
+    if (iRun != maRuns.end())
+        return *iRun;
+    else
+        return SharedPageObjectRun();
+}
+
+InsertAnimator::Implementation::RunContainer::const_iterator
+    InsertAnimator::Implementation::FindRun (const sal_Int32 nRunIndex) const
+{
+    return std::find_if(
+        maRuns.begin(),
+        maRuns.end(),
+        [nRunIndex] (std::shared_ptr<PageObjectRun> const& rRun)
+            { return rRun->mnRunIndex == nRunIndex; });
+}
+
+void InsertAnimator::Implementation::AddRun (const std::shared_ptr<PageObjectRun>& rRun)
+{
+    if (rRun)
+    {
+        maRuns.insert(rRun);
+    }
+    else
+    {
+        OSL_ASSERT(rRun);
+    }
+}
+
+void InsertAnimator::Implementation::RemoveRun (const std::shared_ptr<PageObjectRun>& rRun)
+{
+    if (rRun)
+    {
+        // Do not remove runs that show the space for the insertion indicator.
+        if (rRun->mnLocalInsertIndex == -1)
+        {
+            InsertAnimator::Implementation::RunContainer::const_iterator iRun (FindRun(rRun->mnRunIndex));
+            if (iRun != maRuns.end())
+            {
+                OSL_ASSERT(*iRun == rRun);
+                maRuns.erase(iRun);
+            }
+        }
+    }
+    else
+    {
+        OSL_ASSERT(rRun);
+    }
+}
+
+//===== PageObjectRun =========================================================
+
+PageObjectRun::PageObjectRun (
+    AnimatorAccess& rAnimatorAccess,
+    const sal_Int32 nRunIndex,
+    const sal_Int32 nStartIndex,
+    const sal_Int32 nEndIndex)
+    : mnRunIndex(nRunIndex),
+      mnLocalInsertIndex(-1),
+      mnStartIndex(nStartIndex),
+      mnEndIndex(nEndIndex),
+      mnStartTime(-1),
+      mnAnimationId(controller::Animator::NotAnAnimationId),
+      mrAnimatorAccess(rAnimatorAccess),
+      maAccelerationFunction(
+          controller::AnimationParametricFunction(
+              controller::AnimationBezierFunction (0.1,0.7)))
+{
+    maStartOffset.resize(nEndIndex - nStartIndex + 1);
+    maEndOffset.resize(nEndIndex - nStartIndex + 1);
+}
+
+void PageObjectRun::UpdateOffsets(
+    const InsertPosition& rInsertPosition,
+    const view::Layouter& rLayouter)
+{
+    const bool bIsVertical (rLayouter.GetColumnCount()==1);
+    const sal_Int32 nLocalInsertIndex(bIsVertical
+        ? rInsertPosition.GetRow()
+        : rInsertPosition.GetColumn());
+    if (nLocalInsertIndex == mnLocalInsertIndex)
+        return;
+
+    mnLocalInsertIndex = nLocalInsertIndex;
+
+    model::SlideSorterModel& rModel (mrAnimatorAccess.GetModel());
+    const sal_Int32 nRunLength (mnEndIndex - mnStartIndex + 1);
+    for (sal_Int32 nIndex=0; nIndex<nRunLength; ++nIndex)
+    {
+        model::SharedPageDescriptor pDescriptor(rModel.GetPageDescriptor(nIndex+mnStartIndex));
+        if (pDescriptor)
+            maStartOffset[nIndex] = pDescriptor->GetVisualState().GetLocationOffset();
+        maEndOffset[nIndex] = nIndex < mnLocalInsertIndex
+            ? rInsertPosition.GetLeadingOffset()
+            : rInsertPosition.GetTrailingOffset();
+        if (bIsVertical)
+            maEndOffset[nIndex].setX( 0 );
+        else
+            maEndOffset[nIndex].setY( 0 );
+    }
+    RestartAnimation();
+}
+
+void PageObjectRun::ResetOffsets (const controller::Animator::AnimationMode eMode)
+{
+    mnLocalInsertIndex = -1;
+    const sal_Int32 nRunLength (mnEndIndex - mnStartIndex + 1);
+    model::SlideSorterModel& rModel (mrAnimatorAccess.GetModel());
+    view::SlideSorterView& rView (mrAnimatorAccess.GetView());
+    for (sal_Int32 nIndex=0; nIndex<nRunLength; ++nIndex)
+    {
+        model::SharedPageDescriptor pDescriptor(rModel.GetPageDescriptor(nIndex+mnStartIndex));
+        if (pDescriptor)
+        {
+            if (eMode == controller::Animator::AM_Animated)
+                maStartOffset[nIndex] = pDescriptor->GetVisualState().GetLocationOffset();
+            else
+            {
+                const ::tools::Rectangle aOldBoundingBox (pDescriptor->GetBoundingBox());
+                pDescriptor->GetVisualState().SetLocationOffset(Point(0,0));
+                rView.RequestRepaint(aOldBoundingBox);
+                rView.RequestRepaint(pDescriptor);
+            }
+        }
+        maEndOffset[nIndex] = Point(0,0);
+    }
+    if (eMode == controller::Animator::AM_Animated)
+        RestartAnimation();
+    else
+        mrAnimatorAccess.RemoveRun(shared_from_this());
+}
+
+void PageObjectRun::RestartAnimation()
+{
+    // Stop the current animation.
+    if (mnAnimationId != controller::Animator::NotAnAnimationId)
+    {
+        mrAnimatorAccess.GetAnimator()->RemoveAnimation(mnAnimationId);
+    }
+
+    // Restart the animation.
+    mrAnimatorAccess.AddRun(shared_from_this());
+    auto sharedThis(shared_from_this());
+    mnAnimationId = mrAnimatorAccess.GetAnimator()->AddAnimation(
+        [this] (double const val) { (*this)(val); },
+        [sharedThis] () { sharedThis->mrAnimatorAccess.RemoveRun(sharedThis); }
+        );
+}
+
+void PageObjectRun::operator () (const double nGlobalTime)
+{
+    if (mnStartTime < 0)
+        mnStartTime = nGlobalTime;
+
+    double nLocalTime (nGlobalTime - mnStartTime);
+    if (nLocalTime > 1.0)
+        nLocalTime = 1.0;
+    nLocalTime = maAccelerationFunction(nLocalTime);
+
+    model::SlideSorterModel& rModel (mrAnimatorAccess.GetModel());
+    view::SlideSorterView& rView (mrAnimatorAccess.GetView());
+    for (sal_Int32 nIndex=mnStartIndex; nIndex<=mnEndIndex; ++nIndex)
+    {
+        model::SharedPageDescriptor pDescriptor (rModel.GetPageDescriptor(nIndex));
+        if ( ! pDescriptor)
+            continue;
+        const ::tools::Rectangle aOldBoundingBox (pDescriptor->GetBoundingBox());
+        pDescriptor->GetVisualState().SetLocationOffset(
+            Blend(
+                maStartOffset[nIndex-mnStartIndex],
+                maEndOffset[nIndex-mnStartIndex],
+                nLocalTime));
+
+        // Request a repaint of the old and new bounding box (which largely overlap.)
+        rView.RequestRepaint(aOldBoundingBox);
+        rView.RequestRepaint(pDescriptor);
+    }
+
+    // Call Flush to make
+    // a) animations a bit more smooth and
+    // b) on Mac without the Flush a Reset of the page locations is not properly
+    // visualized when the mouse leaves the window during drag-and-drop.
+    mrAnimatorAccess.GetContentWindow()->GetOutDev()->Flush();
+}
+
+} // end of namespace ::sd::slidesorter::view
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/view/SlsInsertionIndicatorOverlay.cxx b/sd/source/ui/slidesorter/view/SlsInsertionIndicatorOverlay.cxx
new file mode 100644
index 000000000..c1eb0ea90
--- /dev/null
+++ b/sd/source/ui/slidesorter/view/SlsInsertionIndicatorOverlay.cxx
@@ -0,0 +1,360 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <view/SlsInsertionIndicatorOverlay.hxx>
+
+#include <SlideSorter.hxx>
+#include <view/SlideSorterView.hxx>
+#include <view/SlsLayouter.hxx>
+#include <view/SlsPageObjectLayouter.hxx>
+#include <view/SlsTheme.hxx>
+#include "SlsFramePainter.hxx"
+#include "SlsLayeredDevice.hxx"
+#include <DrawDocShell.hxx>
+#include <drawdoc.hxx>
+#include <Window.hxx>
+
+#include <o3tl/safeint.hxx>
+#include <rtl/math.hxx>
+#include <vcl/virdev.hxx>
+#include <basegfx/range/b2drectangle.hxx>
+#include <basegfx/polygon/b2dpolygon.hxx>
+#include <basegfx/polygon/b2dpolygontools.hxx>
+
+namespace {
+
+const double gnPreviewOffsetScale = 1.0 / 8.0;
+
+::tools::Rectangle GrowRectangle (const ::tools::Rectangle& rBox, const sal_Int32 nOffset)
+{
+    return ::tools::Rectangle (
+        rBox.Left() - nOffset,
+        rBox.Top() - nOffset,
+        rBox.Right() + nOffset,
+        rBox.Bottom() + nOffset);
+}
+
+sal_Int32 RoundToInt (const double nValue) { return sal_Int32(::rtl::math::round(nValue)); }
+
+} // end of anonymous namespace
+
+namespace sd::slidesorter::view {
+
+//=====  InsertionIndicatorOverlay  ===========================================
+
+const sal_Int32 gnShadowBorder = 3;
+const sal_Int32 gnLayerIndex = 2;
+
+InsertionIndicatorOverlay::InsertionIndicatorOverlay (SlideSorter& rSlideSorter)
+    : mrSlideSorter(rSlideSorter),
+      mbIsVisible(false),
+      mpShadowPainter(
+          new FramePainter(mrSlideSorter.GetTheme()->GetIcon(Theme::Icon_RawInsertShadow)))
+{
+}
+
+InsertionIndicatorOverlay::~InsertionIndicatorOverlay()
+{
+    // cid#1491947 silence Uncaught exception
+    suppress_fun_call_w_exception(Hide());
+}
+
+void InsertionIndicatorOverlay::Create (const SdTransferable* pTransferable)
+{
+    if (pTransferable == nullptr)
+        return;
+
+    std::shared_ptr<controller::TransferableData> pData (
+        controller::TransferableData::GetFromTransferable(pTransferable));
+    if ( ! pData)
+        return;
+    sal_Int32 nSelectionCount (0);
+    if (pTransferable->HasPageBookmarks())
+        nSelectionCount = pTransferable->GetPageBookmarks().size();
+    else
+    {
+        DrawDocShell* pDataDocShell = dynamic_cast<DrawDocShell*>(pTransferable->GetDocShell().get());
+        if (pDataDocShell != nullptr)
+        {
+            SdDrawDocument* pDataDocument = pDataDocShell->GetDoc();
+            if (pDataDocument != nullptr)
+                nSelectionCount = pDataDocument->GetSdPageCount(PageKind::Standard);
+        }
+    }
+    Create(pData->GetRepresentatives(), nSelectionCount);
+}
+
+void InsertionIndicatorOverlay::Create (
+    const ::std::vector<controller::TransferableData::Representative>& rRepresentatives,
+    const sal_Int32 nSelectionCount)
+{
+    view::Layouter& rLayouter (mrSlideSorter.GetView().GetLayouter());
+    const std::shared_ptr<view::PageObjectLayouter>& pPageObjectLayouter (
+        rLayouter.GetPageObjectLayouter());
+    std::shared_ptr<view::Theme> pTheme (mrSlideSorter.GetTheme());
+    const Size aOriginalPreviewSize (pPageObjectLayouter->GetPreviewSize());
+
+    const double nPreviewScale (0.5);
+    const Size aPreviewSize (
+        RoundToInt(aOriginalPreviewSize.Width()*nPreviewScale),
+        RoundToInt(aOriginalPreviewSize.Height()*nPreviewScale));
+    const sal_Int32 nOffset (
+        RoundToInt(std::min(aPreviewSize.Width(),aPreviewSize.Height()) * gnPreviewOffsetScale));
+
+    // Determine size and offset depending on the number of previews.
+    sal_Int32 nCount (rRepresentatives.size());
+    if (nCount > 0)
+        --nCount;
+    Size aIconSize(
+        aPreviewSize.Width() + 2 * gnShadowBorder + nCount*nOffset,
+        aPreviewSize.Height() + 2 * gnShadowBorder + nCount*nOffset);
+
+    // Create virtual devices for bitmap and mask whose bitmaps later be
+    // combined to form the BitmapEx of the icon.
+    ScopedVclPtrInstance<VirtualDevice> pContent(
+        *mrSlideSorter.GetContentWindow()->GetOutDev(), DeviceFormat::DEFAULT, DeviceFormat::DEFAULT);
+    pContent->SetOutputSizePixel(aIconSize);
+
+    pContent->SetFillColor();
+    pContent->SetLineColor(pTheme->GetColor(Theme::Color_PreviewBorder));
+    const Point aOffset = PaintRepresentatives(*pContent, aPreviewSize, nOffset, rRepresentatives);
+
+    PaintPageCount(*pContent, nSelectionCount, aPreviewSize, aOffset);
+
+    maIcon = pContent->GetBitmapEx(Point(0,0), aIconSize);
+    maIcon.Scale(aIconSize);
+}
+
+Point InsertionIndicatorOverlay::PaintRepresentatives (
+    OutputDevice& rContent,
+    const Size& rPreviewSize,
+    const sal_Int32 nOffset,
+    const ::std::vector<controller::TransferableData::Representative>& rRepresentatives) const
+{
+    const Point aOffset (0,rRepresentatives.size()==1 ? -nOffset : 0);
+
+    // Paint the pages.
+    Point aPageOffset (0,0);
+    double nTransparency (0);
+    const BitmapEx aExclusionOverlay (mrSlideSorter.GetTheme()->GetIcon(Theme::Icon_HideSlideOverlay));
+    for (sal_Int32 nIndex=2; nIndex>=0; --nIndex)
+    {
+        if (rRepresentatives.size() <= o3tl::make_unsigned(nIndex))
+            continue;
+        switch(nIndex)
+        {
+            case 0 :
+                aPageOffset = Point(0, nOffset);
+                nTransparency = 0.85;
+                break;
+            case 1:
+                aPageOffset = Point(nOffset, 0);
+                nTransparency = 0.75;
+                break;
+            case 2:
+                aPageOffset = Point(2*nOffset, 2*nOffset);
+                nTransparency = 0.65;
+                break;
+        }
+        aPageOffset += aOffset;
+        aPageOffset.AdjustX(gnShadowBorder );
+        aPageOffset.AdjustY(gnShadowBorder );
+
+        // Paint the preview.
+        BitmapEx aPreview (rRepresentatives[nIndex].maBitmap);
+        aPreview.Scale(rPreviewSize, BmpScaleFlag::BestQuality);
+        rContent.DrawBitmapEx(aPageOffset, aPreview);
+
+        // When the page is marked as excluded from the slide show then
+        // paint an overlay that visualizes this.
+        if (rRepresentatives[nIndex].mbIsExcluded)
+        {
+            const vcl::Region aSavedClipRegion (rContent.GetClipRegion());
+            rContent.IntersectClipRegion(::tools::Rectangle(aPageOffset, rPreviewSize));
+            // Paint bitmap tiled over the preview to mark it as excluded.
+            const sal_Int32 nIconWidth (aExclusionOverlay.GetSizePixel().Width());
+            const sal_Int32 nIconHeight (aExclusionOverlay.GetSizePixel().Height());
+            if (nIconWidth>0 && nIconHeight>0)
+            {
+                for (::tools::Long nX=0; nX<rPreviewSize.Width(); nX+=nIconWidth)
+                    for (::tools::Long nY=0; nY<rPreviewSize.Height(); nY+=nIconHeight)
+                        rContent.DrawBitmapEx(Point(nX,nY)+aPageOffset, aExclusionOverlay);
+            }
+            rContent.SetClipRegion(aSavedClipRegion);
+        }
+
+        // Tone down the bitmap.  The further back the darker it becomes.
+        ::tools::Rectangle aBox (
+            aPageOffset.X(),
+            aPageOffset.Y(),
+            aPageOffset.X()+rPreviewSize.Width()-1,
+            aPageOffset.Y()+rPreviewSize.Height()-1);
+        rContent.SetFillColor(COL_BLACK);
+        rContent.SetLineColor();
+        rContent.DrawTransparent(
+            basegfx::B2DHomMatrix(),
+            ::basegfx::B2DPolyPolygon(::basegfx::utils::createPolygonFromRect(
+                ::basegfx::B2DRectangle(aBox.Left(), aBox.Top(), aBox.Right()+1, aBox.Bottom()+1),
+                0,
+                0)),
+            nTransparency);
+
+        // Draw border around preview.
+        ::tools::Rectangle aBorderBox (GrowRectangle(aBox, 1));
+        rContent.SetLineColor(COL_GRAY);
+        rContent.SetFillColor();
+        rContent.DrawRect(aBorderBox);
+
+        // Draw shadow around preview.
+        mpShadowPainter->PaintFrame(rContent, aBorderBox);
+    }
+
+    return aPageOffset;
+}
+
+void InsertionIndicatorOverlay::PaintPageCount (
+    OutputDevice& rDevice,
+    const sal_Int32 nSelectionCount,
+    const Size& rPreviewSize,
+    const Point& rFirstPageOffset) const
+{
+    // Paint the number of slides.
+    std::shared_ptr<view::Theme> pTheme (mrSlideSorter.GetTheme());
+    std::shared_ptr<vcl::Font> pFont(Theme::GetFont(Theme::Font_PageCount, rDevice));
+    if (!pFont)
+        return;
+
+    OUString sNumber (OUString::number(nSelectionCount));
+
+    // Determine the size of the (painted) text and create a bounding
+    // box that centers the text on the first preview.
+    rDevice.SetFont(*pFont);
+    ::tools::Rectangle aTextBox;
+    rDevice.GetTextBoundRect(aTextBox, sNumber);
+    Point aTextOffset (aTextBox.TopLeft());
+    Size aTextSize (aTextBox.GetSize());
+    // Place text inside the first page preview.
+    Point aTextLocation(rFirstPageOffset);
+    // Center the text.
+    aTextLocation += Point(
+        (rPreviewSize.Width()-aTextBox.GetWidth())/2,
+        (rPreviewSize.Height()-aTextBox.GetHeight())/2);
+    aTextBox = ::tools::Rectangle(aTextLocation, aTextSize);
+
+    // Paint background, border and text.
+    static const sal_Int32 nBorder = 5;
+    rDevice.SetFillColor(pTheme->GetColor(Theme::Color_Selection));
+    rDevice.SetLineColor(pTheme->GetColor(Theme::Color_Selection));
+    rDevice.DrawRect(GrowRectangle(aTextBox, nBorder));
+
+    rDevice.SetFillColor();
+    rDevice.SetLineColor(pTheme->GetColor(Theme::Color_PageCountFontColor));
+    rDevice.DrawRect(GrowRectangle(aTextBox, nBorder-1));
+
+    rDevice.SetTextColor(pTheme->GetColor(Theme::Color_PageCountFontColor));
+    rDevice.DrawText(aTextBox.TopLeft()-aTextOffset, sNumber);
+}
+
+void InsertionIndicatorOverlay::SetLocation (const Point& rLocation)
+{
+    const Point  aTopLeft (
+        rLocation - Point(
+            maIcon.GetSizePixel().Width()/2,
+            maIcon.GetSizePixel().Height()/2));
+    if (maLocation != aTopLeft)
+    {
+        const ::tools::Rectangle aOldBoundingBox (GetBoundingBox());
+
+        maLocation = aTopLeft;
+
+        if (mpLayerInvalidator && IsVisible())
+        {
+            mpLayerInvalidator->Invalidate(aOldBoundingBox);
+            mpLayerInvalidator->Invalidate(GetBoundingBox());
+        }
+    }
+}
+
+void InsertionIndicatorOverlay::Paint (
+    OutputDevice& rDevice,
+    const ::tools::Rectangle&)
+{
+    if ( ! IsVisible())
+        return;
+
+    rDevice.DrawImage(maLocation, Image(maIcon));
+}
+
+void InsertionIndicatorOverlay::SetLayerInvalidator (const SharedILayerInvalidator& rpInvalidator)
+{
+    mpLayerInvalidator = rpInvalidator;
+
+    if (mbIsVisible && mpLayerInvalidator)
+        mpLayerInvalidator->Invalidate(GetBoundingBox());
+}
+
+void InsertionIndicatorOverlay::Show()
+{
+    if (  mbIsVisible)
+        return;
+
+    mbIsVisible = true;
+
+    std::shared_ptr<LayeredDevice> pLayeredDevice (
+        mrSlideSorter.GetView().GetLayeredDevice());
+    if (pLayeredDevice)
+    {
+        pLayeredDevice->RegisterPainter(shared_from_this(), gnLayerIndex);
+        if (mpLayerInvalidator)
+            mpLayerInvalidator->Invalidate(GetBoundingBox());
+    }
+}
+
+void InsertionIndicatorOverlay::Hide()
+{
+    if (!mbIsVisible)
+        return;
+
+    mbIsVisible = false;
+
+    std::shared_ptr<LayeredDevice> pLayeredDevice (
+        mrSlideSorter.GetView().GetLayeredDevice());
+    if (pLayeredDevice)
+    {
+        if (mpLayerInvalidator)
+            mpLayerInvalidator->Invalidate(GetBoundingBox());
+        pLayeredDevice->RemovePainter(shared_from_this(), gnLayerIndex);
+    }
+}
+
+::tools::Rectangle InsertionIndicatorOverlay::GetBoundingBox() const
+{
+    return ::tools::Rectangle(maLocation, maIcon.GetSizePixel());
+}
+
+Size InsertionIndicatorOverlay::GetSize() const
+{
+    return Size(
+        maIcon.GetSizePixel().Width() + 10,
+        maIcon.GetSizePixel().Height() + 10);
+}
+
+} // end of namespace ::sd::slidesorter::view
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/view/SlsLayeredDevice.cxx b/sd/source/ui/slidesorter/view/SlsLayeredDevice.cxx
new file mode 100644
index 000000000..b41bbe307
--- /dev/null
+++ b/sd/source/ui/slidesorter/view/SlsLayeredDevice.cxx
@@ -0,0 +1,491 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "SlsLayeredDevice.hxx"
+#include <Window.hxx>
+
+#include <vcl/virdev.hxx>
+#include <sal/log.hxx>
+#include <o3tl/safeint.hxx>
+#include <osl/diagnose.h>
+
+#include <tools/gen.hxx>
+#include <tools/fract.hxx>
+
+#include <functional>
+
+namespace sd::slidesorter::view {
+
+namespace {
+const sal_Int32 gnMaximumLayerCount = 8;
+
+class LayerInvalidator : public ILayerInvalidator
+{
+public:
+    LayerInvalidator (
+        const std::shared_ptr<LayeredDevice>& rpLayeredDevice,
+        sd::Window *pTargetWindow,
+        const int nLayer)
+        : mpLayeredDevice(rpLayeredDevice),
+          mpTargetWindow(pTargetWindow),
+          mnLayer(nLayer)
+    {
+    }
+
+    virtual void Invalidate (const ::tools::Rectangle& rInvalidationBox) override
+    {
+        mpLayeredDevice->Invalidate(rInvalidationBox, mnLayer);
+        mpTargetWindow->Invalidate(rInvalidationBox);
+    }
+
+private:
+    const std::shared_ptr<LayeredDevice> mpLayeredDevice;
+    VclPtr<sd::Window> mpTargetWindow;
+    const int mnLayer;
+};
+
+void DeviceCopy (
+    vcl::RenderContext& rTargetDevice,
+    vcl::RenderContext const & rSourceDevice,
+    const ::tools::Rectangle& rBox)
+{
+    rTargetDevice.DrawOutDev(
+        rBox.TopLeft(),
+        rBox.GetSize(),
+        rBox.TopLeft(),
+        rBox.GetSize(),
+        rSourceDevice);
+}
+
+void ForAllRectangles (const vcl::Region& rRegion, const std::function<void (const ::tools::Rectangle&)>& aFunction)
+{
+    OSL_ASSERT(aFunction);
+    RectangleVector aRectangles;
+    rRegion.GetRegionRectangles(aRectangles);
+
+    if(aRectangles.empty())
+    {
+        aFunction(::tools::Rectangle());
+    }
+    else
+    {
+        for(const auto& rRect : aRectangles)
+        {
+            aFunction(rRect);
+        }
+
+        //Region aMutableRegionCopy (rRegion);
+        //RegionHandle aHandle(aMutableRegionCopy.BeginEnumRects());
+        //Rectangle aBox;
+        //while (aMutableRegionCopy.GetEnumRects(aHandle, aBox))
+        //    aFunction(aBox);
+        //aMutableRegionCopy.EndEnumRects(aHandle);
+    }
+}
+
+class Layer
+{
+public:
+    Layer();
+    Layer(const Layer&) = delete;
+    Layer& operator=(const Layer&) = delete;
+
+    void Initialize (sd::Window *pTargetWindow);
+    void InvalidateRectangle (const ::tools::Rectangle& rInvalidationBox);
+    void InvalidateRegion (const vcl::Region& rInvalidationRegion);
+    void Validate (const MapMode& rMapMode);
+    void Repaint (
+        OutputDevice& rTargetDevice,
+        const ::tools::Rectangle& rRepaintRectangle);
+    void Resize (const Size& rSize);
+    void AddPainter (const SharedILayerPainter& rpPainter);
+    void RemovePainter (const SharedILayerPainter& rpPainter);
+    bool HasPainter() const;
+    void Dispose();
+
+private:
+    ScopedVclPtr<VirtualDevice> mpLayerDevice;
+    ::std::vector<SharedILayerPainter> maPainters;
+    vcl::Region maInvalidationRegion;
+
+    void ValidateRectangle (const ::tools::Rectangle& rBox);
+};
+typedef std::shared_ptr<Layer> SharedLayer;
+
+} // end of anonymous namespace
+
+class LayeredDevice::LayerContainer
+{
+public:
+    LayerContainer()  {}
+
+    bool empty() const { return mvLayers.empty(); }
+
+    size_t size() const { return mvLayers.size(); }
+
+    const SharedLayer& back() const { return mvLayers.back(); }
+
+    ::std::vector<SharedLayer>::const_iterator begin() const { return mvLayers.begin(); }
+    ::std::vector<SharedLayer>::const_iterator end() const { return mvLayers.end(); }
+
+    void clear() { mvLayers.clear(); }
+
+    void pop_back() { mvLayers.pop_back(); }
+
+    void resize(size_t n) { mvLayers.resize(n); }
+
+    SharedLayer& operator[](size_t i) { return mvLayers[i]; }
+
+private:
+    ::std::vector<SharedLayer> mvLayers;
+};
+
+//===== LayeredDevice =========================================================
+
+LayeredDevice::LayeredDevice (const VclPtr<sd::Window>& pTargetWindow)
+    : mpTargetWindow(pTargetWindow),
+      mpLayers(new LayerContainer()),
+      mpBackBuffer(VclPtr<VirtualDevice>::Create(*mpTargetWindow->GetOutDev())),
+      maSavedMapMode(pTargetWindow->GetMapMode())
+{
+    mpBackBuffer->SetOutputSizePixel(mpTargetWindow->GetSizePixel());
+}
+
+LayeredDevice::~LayeredDevice()
+{
+}
+
+void LayeredDevice::Invalidate (
+    const ::tools::Rectangle& rInvalidationArea,
+    const sal_Int32 nLayer)
+{
+    if (nLayer<0 || o3tl::make_unsigned(nLayer)>=mpLayers->size())
+    {
+        OSL_ASSERT(nLayer>=0 && o3tl::make_unsigned(nLayer)<mpLayers->size());
+        return;
+    }
+
+    (*mpLayers)[nLayer]->InvalidateRectangle(rInvalidationArea);
+}
+
+void LayeredDevice::InvalidateAllLayers (const ::tools::Rectangle& rInvalidationArea)
+{
+    for (size_t nLayer=0; nLayer<mpLayers->size(); ++nLayer)
+        (*mpLayers)[nLayer]->InvalidateRectangle(rInvalidationArea);
+}
+
+void LayeredDevice::InvalidateAllLayers (const vcl::Region& rInvalidationRegion)
+{
+    for (size_t nLayer=0; nLayer<mpLayers->size(); ++nLayer)
+        (*mpLayers)[nLayer]->InvalidateRegion(rInvalidationRegion);
+}
+
+void LayeredDevice::RegisterPainter (
+    const SharedILayerPainter& rpPainter,
+    const sal_Int32 nLayer)
+{
+    OSL_ASSERT(mpLayers);
+    if ( ! rpPainter)
+    {
+        OSL_ASSERT(rpPainter);
+        return;
+    }
+    if (nLayer<0 || nLayer>=gnMaximumLayerCount)
+    {
+        OSL_ASSERT(nLayer>=0 && nLayer<gnMaximumLayerCount);
+        return;
+    }
+
+    // Provide the layers.
+    if (o3tl::make_unsigned(nLayer) >= mpLayers->size())
+    {
+        const sal_Int32 nOldLayerCount (mpLayers->size());
+        mpLayers->resize(nLayer+1);
+
+        for (size_t nIndex=nOldLayerCount; nIndex<mpLayers->size(); ++nIndex)
+            (*mpLayers)[nIndex] = std::make_shared<Layer>();
+    }
+
+    (*mpLayers)[nLayer]->AddPainter(rpPainter);
+    if (nLayer == 0)
+        (*mpLayers)[nLayer]->Initialize(mpTargetWindow);
+
+    rpPainter->SetLayerInvalidator(
+        std::make_shared<LayerInvalidator>(shared_from_this(),mpTargetWindow,nLayer));
+}
+
+void LayeredDevice::RemovePainter (
+    const SharedILayerPainter& rpPainter,
+    const sal_Int32 nLayer)
+{
+    if ( ! rpPainter)
+    {
+        OSL_ASSERT(rpPainter);
+        return;
+    }
+    if (nLayer<0 || o3tl::make_unsigned(nLayer)>=mpLayers->size())
+    {
+        OSL_ASSERT(nLayer>=0 && o3tl::make_unsigned(nLayer)<mpLayers->size());
+        return;
+    }
+
+    rpPainter->SetLayerInvalidator(SharedILayerInvalidator());
+
+    (*mpLayers)[nLayer]->RemovePainter(rpPainter);
+
+    // Remove top most layers that do not contain any painters.
+    while ( ! mpLayers->empty() && ! mpLayers->back()->HasPainter())
+        mpLayers->pop_back();
+}
+
+void LayeredDevice::Repaint (const vcl::Region& rRepaintRegion)
+{
+    // Validate the contents of all layers (that have their own devices.)
+    for (auto const& it : *mpLayers)
+    {
+        it->Validate(mpTargetWindow->GetMapMode());
+    }
+
+    ForAllRectangles(rRepaintRegion,
+            [this] (::tools::Rectangle const& r) { this->RepaintRectangle(r); });
+}
+
+void LayeredDevice::RepaintRectangle (const ::tools::Rectangle& rRepaintRectangle)
+{
+    if (mpLayers->empty())
+        return;
+    else if (mpLayers->size() == 1)
+    {
+        // Just copy the main layer into the target device.
+        (*mpLayers)[0]->Repaint(*mpTargetWindow->GetOutDev(), rRepaintRectangle);
+    }
+    else
+    {
+        // Paint all layers first into the back buffer (to avoid flickering
+        // due to synchronous paints) and then copy that into the target
+        // device.
+        mpBackBuffer->SetMapMode(mpTargetWindow->GetMapMode());
+        for (auto const& it : *mpLayers)
+        {
+            it->Repaint(*mpBackBuffer, rRepaintRectangle);
+        }
+        DeviceCopy(*mpTargetWindow->GetOutDev(), *mpBackBuffer, rRepaintRectangle);
+    }
+}
+
+void LayeredDevice::Resize()
+{
+    const Size aSize (mpTargetWindow->GetSizePixel());
+    mpBackBuffer->SetOutputSizePixel(aSize);
+    for (auto const& it : *mpLayers)
+    {
+        it->Resize(aSize);
+    }
+}
+
+void LayeredDevice::Dispose()
+{
+    for (auto const& it : *mpLayers)
+    {
+        it->Dispose();
+    }
+    mpLayers->clear();
+}
+
+bool LayeredDevice::HandleMapModeChange()
+{
+    const MapMode& rMapMode (mpTargetWindow->GetMapMode());
+    if (maSavedMapMode == rMapMode)
+        return false;
+
+    const ::tools::Rectangle aLogicWindowBox (
+        mpTargetWindow->PixelToLogic(::tools::Rectangle(Point(0,0), mpTargetWindow->GetSizePixel())));
+    if (maSavedMapMode.GetScaleX() != rMapMode.GetScaleX()
+        || maSavedMapMode.GetScaleY() != rMapMode.GetScaleY()
+        || maSavedMapMode.GetMapUnit() != rMapMode.GetMapUnit())
+    {
+        // When the scale has changed then we have to paint everything.
+        InvalidateAllLayers(aLogicWindowBox);
+    }
+    else if (maSavedMapMode.GetOrigin() != rMapMode.GetOrigin())
+    {
+        // Window has been scrolled.  Adapt contents of backbuffers and
+        // layer devices.
+        const Point aDelta (rMapMode.GetOrigin() - maSavedMapMode.GetOrigin());
+        mpBackBuffer->CopyArea(
+            aLogicWindowBox.TopLeft(),
+            mpTargetWindow->PixelToLogic(Point(0,0), maSavedMapMode),
+            aLogicWindowBox.GetSize());
+
+        // Invalidate the area(s) that have been exposed.
+        const ::tools::Rectangle aWindowBox (Point(0,0), mpTargetWindow->GetSizePixel());
+        if (aDelta.Y() < 0)
+            InvalidateAllLayers(mpTargetWindow->PixelToLogic(::tools::Rectangle(
+                aWindowBox.Left(),
+                aWindowBox.Bottom()+aDelta.Y(),
+                aWindowBox.Right(),
+                aWindowBox.Bottom())));
+        else if (aDelta.Y() > 0)
+            InvalidateAllLayers(mpTargetWindow->PixelToLogic(::tools::Rectangle(
+                aWindowBox.Left(),
+                aWindowBox.Top(),
+                aWindowBox.Right(),
+                aWindowBox.Top()+aDelta.Y())));
+        if (aDelta.X() < 0)
+            InvalidateAllLayers(mpTargetWindow->PixelToLogic(::tools::Rectangle(
+                aWindowBox.Right()+aDelta.X(),
+                aWindowBox.Top(),
+                aWindowBox.Right(),
+                aWindowBox.Bottom())));
+        else if (aDelta.X() > 0)
+            InvalidateAllLayers(mpTargetWindow->PixelToLogic(::tools::Rectangle(
+                aWindowBox.Left(),
+                aWindowBox.Top(),
+                aWindowBox.Left()+aDelta.X(),
+                aWindowBox.Bottom())));
+    }
+    else
+    {
+        // Can this happen?  Lets trigger a warning when it does.
+        OSL_ASSERT(false);
+    }
+
+    maSavedMapMode = rMapMode;
+
+    return true;
+}
+
+//===== Layer =================================================================
+
+Layer::Layer()
+{
+}
+
+void Layer::Initialize (sd::Window *pTargetWindow)
+{
+#if 0
+    (void)pTargetWindow;
+#else
+    if ( ! mpLayerDevice)
+    {
+        mpLayerDevice.disposeAndReset(VclPtr<VirtualDevice>::Create(*pTargetWindow->GetOutDev()));
+        mpLayerDevice->SetOutputSizePixel(pTargetWindow->GetSizePixel());
+    }
+#endif
+}
+
+void Layer::InvalidateRectangle (const ::tools::Rectangle& rInvalidationBox)
+{
+    maInvalidationRegion.Union(rInvalidationBox);
+}
+
+void Layer::InvalidateRegion (const vcl::Region& rInvalidationRegion)
+{
+    maInvalidationRegion.Union(rInvalidationRegion);
+}
+
+void Layer::Validate (const MapMode& rMapMode)
+{
+    if (mpLayerDevice && ! maInvalidationRegion.IsEmpty())
+    {
+        vcl::Region aRegion (maInvalidationRegion);
+        maInvalidationRegion.SetEmpty();
+
+        mpLayerDevice->SetMapMode(rMapMode);
+        ForAllRectangles(
+            aRegion,
+            [this] (::tools::Rectangle const& r) { return this->ValidateRectangle(r); });
+    }
+}
+
+void Layer::ValidateRectangle (const ::tools::Rectangle& rBox)
+{
+    if ( ! mpLayerDevice)
+        return;
+    const vcl::Region aSavedClipRegion (mpLayerDevice->GetClipRegion());
+    mpLayerDevice->IntersectClipRegion(rBox);
+
+    for (const auto& rxPainter : maPainters)
+    {
+        rxPainter->Paint(*mpLayerDevice, rBox);
+    }
+
+    mpLayerDevice->SetClipRegion(aSavedClipRegion);
+}
+
+void Layer::Repaint (
+    OutputDevice& rTargetDevice,
+    const ::tools::Rectangle& rRepaintRectangle)
+{
+    if (mpLayerDevice)
+    {
+        DeviceCopy(rTargetDevice, *mpLayerDevice, rRepaintRectangle);
+    }
+    else
+    {
+        for (auto const& it : maPainters)
+        {
+            it->Paint(rTargetDevice, rRepaintRectangle);
+        }
+    }
+}
+
+void Layer::Resize (const Size& rSize)
+{
+    if (mpLayerDevice)
+    {
+        mpLayerDevice->SetOutputSizePixel(rSize);
+        maInvalidationRegion = ::tools::Rectangle(Point(0,0), rSize);
+    }
+}
+
+void Layer::AddPainter (const SharedILayerPainter& rpPainter)
+{
+    OSL_ASSERT(::std::find(maPainters.begin(), maPainters.end(), rpPainter) == maPainters.end());
+
+    maPainters.push_back(rpPainter);
+}
+
+void Layer::RemovePainter (const SharedILayerPainter& rpPainter)
+{
+    const ::std::vector<SharedILayerPainter>::iterator iPainter (
+        ::std::find(maPainters.begin(), maPainters.end(), rpPainter));
+    if (iPainter != maPainters.end())
+    {
+        maPainters.erase(iPainter);
+    }
+    else
+    {
+        SAL_WARN("sd", "LayeredDevice::RemovePainter called for painter that is not registered");
+    }
+}
+
+bool Layer::HasPainter() const
+{
+    return !maPainters.empty();
+}
+
+void Layer::Dispose()
+{
+    maPainters.clear();
+}
+
+} // end of namespace ::sd::slidesorter::view
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/view/SlsLayeredDevice.hxx b/sd/source/ui/slidesorter/view/SlsLayeredDevice.hxx
new file mode 100644
index 000000000..5ec0d0e9f
--- /dev/null
+++ b/sd/source/ui/slidesorter/view/SlsLayeredDevice.hxx
@@ -0,0 +1,84 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <view/SlsILayerPainter.hxx>
+
+#include <vcl/vclptr.hxx>
+#include <vcl/mapmod.hxx>
+
+#include <memory>
+
+namespace sd { class Window; }
+namespace tools { class Rectangle; }
+namespace vcl { class Region; }
+
+class VirtualDevice;
+
+namespace sd::slidesorter::view {
+
+/** A simple wrapper around an OutputDevice that provides support for
+    independent layers and buffering.
+    Each layer may contain any number of painters.
+*/
+class LayeredDevice
+    : public std::enable_shared_from_this<LayeredDevice>
+
+{
+public:
+    explicit LayeredDevice (const VclPtr<sd::Window>& pTargetWindow);
+    ~LayeredDevice ();
+
+    void Invalidate (
+        const ::tools::Rectangle& rInvalidationBox,
+        const sal_Int32 nLayer);
+    void InvalidateAllLayers (
+        const ::tools::Rectangle& rInvalidationBox);
+    void InvalidateAllLayers (
+        const vcl::Region& rInvalidationRegion);
+
+    void RegisterPainter (
+        const SharedILayerPainter& rPainter,
+        const sal_Int32 nLayer);
+
+    void RemovePainter (
+        const SharedILayerPainter& rPainter,
+        const sal_Int32 nLayer);
+
+    bool HandleMapModeChange();
+    void Repaint (const vcl::Region& rRepaintRegion);
+
+    void Resize();
+
+    void Dispose();
+
+private:
+    VclPtr<sd::Window> mpTargetWindow;
+    class LayerContainer;
+    std::unique_ptr<LayerContainer> mpLayers;
+    ScopedVclPtr<VirtualDevice> mpBackBuffer;
+    MapMode maSavedMapMode;
+
+    void RepaintRectangle (const ::tools::Rectangle& rRepaintRectangle);
+};
+
+} // end of namespace ::sd::slidesorter::view
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/view/SlsLayouter.cxx b/sd/source/ui/slidesorter/view/SlsLayouter.cxx
new file mode 100644
index 000000000..21f0be13c
--- /dev/null
+++ b/sd/source/ui/slidesorter/view/SlsLayouter.cxx
@@ -0,0 +1,1225 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <view/SlsPageObjectLayouter.hxx>
+#include <view/SlsTheme.hxx>
+#include <view/SlsLayouter.hxx>
+#include <model/SlideSorterModel.hxx>
+#include <model/SlsPageDescriptor.hxx>
+#include <Window.hxx>
+#include <osl/diagnose.h>
+
+namespace sd::slidesorter::view {
+
+class Layouter::Implementation
+{
+public:
+    VclPtr<sd::Window> mpWindow;
+    static const sal_Int32 mnRequestedLeftBorder = 5;
+    static const sal_Int32 mnRequestedRightBorder = 5;
+    static const sal_Int32 mnRequestedTopBorder = 5;
+    static const sal_Int32 mnRequestedBottomBorder = 5;
+    sal_Int32 mnLeftBorder;
+    sal_Int32 mnRightBorder;
+    sal_Int32 mnTopBorder;
+    sal_Int32 mnBottomBorder;
+    static const sal_Int32 gnVerticalGap = 10 - 2*Theme_FocusIndicatorWidth;
+    static const sal_Int32 gnHorizontalGap = 10 - 2*Theme_FocusIndicatorWidth;
+    Size      maMinimalSize;
+    Size      maPreferredSize;
+    Size      maMaximalSize;
+    sal_Int32 mnMinimalColumnCount;
+    sal_Int32 mnMaximalColumnCount;
+    sal_Int32 mnPageCount;
+    sal_Int32 mnColumnCount;
+    sal_Int32 mnRowCount;
+    /// The maximum number of columns.  Can only be larger than the current
+    /// number of columns when there are not enough pages to fill all
+    /// available columns.
+    sal_Int32 mnMaxColumnCount;
+    /// The maximum number of rows.  Can only be larger than the current
+    /// number of rows when there are not enough pages to fill all available
+    /// rows.
+    sal_Int32 mnMaxRowCount;
+    Size maPageObjectSize;
+    std::shared_ptr<PageObjectLayouter> mpPageObjectLayouter;
+    std::shared_ptr<view::Theme> mpTheme;
+
+    /** Specify how the gap between two page objects is associated with the
+      page objects.
+    */
+    enum GapMembership {
+        GM_NONE,       // Gap is not associated with any page object.
+        GM_PREVIOUS,   // The whole gap is associated with the previous page
+                       // object (left or above the gap.)
+        GM_BOTH,       // Half of the gap is associated with previous, half
+                       // with the next page object.
+        GM_NEXT,       // The whole gap is associated with the next page
+                       // object (right or below the gap.)
+        GM_PAGE_BORDER
+    };
+
+    static Implementation* Create (
+        const Implementation& rImplementation,
+        const Layouter::Orientation eOrientation);
+
+    virtual Layouter::Orientation GetOrientation() const = 0;
+
+    bool Rearrange (
+        const Size& rWindowSize,
+        const Size& rPreviewModelSize,
+        const sal_uInt32 nPageCount);
+
+    /** Calculate the row that the point with the given vertical coordinate
+        is over.  The horizontal component is ignored.
+        @param nYPosition
+            Vertical position in model coordinates.
+        @param bIncludeBordersAndGaps
+            When this flag is <TRUE/> then the area of borders and gaps are
+            interpreted as belonging to one of the rows.
+        @param eGapMembership
+            Specifies to what row the gap areas belong.  Here GM_NONE
+            corresponds to bIncludeBordersAndGaps being <FALSE/>.  When
+            GM_BOTH is given then the upper half is associated to the row
+            above and the lower half to the row below.  Values of
+            GM_PREVIOUS and GM_NEXT associate the whole gap area with the
+            row above or below respectively.
+    */
+    sal_Int32 GetRowAtPosition (
+        sal_Int32 nYPosition,
+        bool bIncludeBordersAndGaps,
+        GapMembership eGapMembership) const;
+
+    /** Calculate the column that the point with the given horizontal
+        coordinate is over.  The vertical component is ignored.
+        @param nXPosition
+            Horizontal position in model coordinates.
+        @param bIncludeBordersAndGaps
+            When this flag is <TRUE/> then the area of borders and gaps are
+            interpreted as belonging to one of the columns.
+        @param eGapMembership
+            Specifies to what column the gap areas belong.
+    */
+    sal_Int32 GetColumnAtPosition (
+        sal_Int32 nXPosition,
+        bool bIncludeBordersAndGaps,
+        GapMembership eGapMembership) const;
+
+    /** This method is typically called from GetRowAtPosition() and
+        GetColumnAtPosition() to handle a position that lies inside the gap
+        between two adjacent rows or columns.
+        @param nDistanceIntoGap
+            Vertical distance from the bottom of the upper row down into the
+            gap or horizontal distance from the right edge right into the
+            gap.
+        @param eGapMemberhship
+            This value decides what areas in the gap belong to which (or no)
+            row or column.
+        @param nIndex
+            The row index of the upper row or the column index of the left
+            column.
+        @param nGap
+             Width or height of the gap in model coordinates between the
+             page borders.
+        @return
+           Returns either the index of the upper row (as given as nRow), the
+           index of the lower row (nRow+1) or -1 to indicate that the
+           position belongs to no row.
+        */
+    static sal_Int32 ResolvePositionInGap (
+        sal_Int32 nDistanceIntoGap,
+        GapMembership eGapMembership,
+        sal_Int32 nIndex,
+        sal_Int32 nGap);
+
+    /** Calculate the logical part of the insert position, i.e. the page
+        after which to insert.
+    */
+    virtual void CalculateLogicalInsertPosition (
+        const Point& rModelPosition,
+        InsertPosition& rPosition) const = 0;
+
+    /** Calculate the geometrical part of the insert position, i.e. the
+        location of where to display the insertion indicator and the
+        distances about which the leading and trailing pages have to be
+        moved to make room for the indicator.
+    */
+    void CalculateGeometricPosition (
+        InsertPosition& rPosition,
+        const Size& rIndicatorSize,
+        const bool bIsVertical,
+        model::SlideSorterModel const & rModel) const;
+
+    /** Return the bounding box of the preview or, when selected, of the page
+        object.  Thus, it returns something like a visual bounding box.
+    */
+    ::tools::Rectangle GetInnerBoundingBox (
+        model::SlideSorterModel const & rModel,
+        const sal_Int32 nIndex) const;
+
+    Range GetValidHorizontalSizeRange() const;
+    Range GetValidVerticalSizeRange() const;
+
+    Range GetRangeOfVisiblePageObjects (const ::tools::Rectangle& aVisibleArea) const;
+    sal_Int32 GetIndex (
+        const sal_Int32 nRow,
+        const sal_Int32 nColumn,
+        const bool bClampToValidRange) const;
+
+        ::tools::Rectangle GetPageObjectBox (
+        const sal_Int32 nIndex,
+        const bool bIncludeBorderAndGap = false) const;
+
+    ::tools::Rectangle GetPageObjectBox (
+        const sal_Int32 nRow,
+        const sal_Int32 nColumn) const;
+
+    ::tools::Rectangle AddBorderAndGap (
+        const ::tools::Rectangle& rBoundingBox,
+        const sal_Int32 nRow,
+        const sal_Int32 nColumn) const;
+
+    ::tools::Rectangle GetTotalBoundingBox() const;
+
+    virtual ~Implementation();
+
+protected:
+    Implementation (
+        sd::Window *pWindow,
+        const std::shared_ptr<view::Theme>& rpTheme);
+    explicit Implementation (const Implementation& rImplementation);
+
+    virtual void CalculateRowAndColumnCount (const Size& rWindowSize) = 0;
+    virtual void CalculateMaxRowAndColumnCount (const Size& rWindowSize) = 0;
+    virtual Size CalculateTargetSize (
+        const Size& rWindowSize) const = 0;
+    Size GetTargetSize (
+        const Size& rWindowSize,
+        const bool bCalculateWidth,
+        const bool bCalculateHeight) const;
+    void CalculateVerticalLogicalInsertPosition (
+        const Point& rModelPosition,
+        InsertPosition& rPosition) const;
+};
+
+namespace {
+
+/** The vertical layouter has one column and as many rows as there are
+    pages.
+*/
+class VerticalImplementation : public Layouter::Implementation
+{
+public:
+    explicit VerticalImplementation (const Implementation& rImplementation);
+
+    virtual Layouter::Orientation GetOrientation() const override;
+
+    void CalculateLogicalInsertPosition (
+        const Point& rModelPosition,
+        InsertPosition& rPosition) const override;
+
+protected:
+    virtual void CalculateRowAndColumnCount (const Size& rWindowSize) override;
+    virtual void CalculateMaxRowAndColumnCount (const Size& rWindowSize) override;
+    virtual Size CalculateTargetSize (
+        const Size& rWindowSize) const override;
+};
+
+/** The horizontal layouter has one row and as many columns as there are
+    pages.
+*/
+class HorizontalImplementation : public Layouter::Implementation
+{
+public:
+    explicit HorizontalImplementation(const Implementation& rImplementation);
+
+    virtual Layouter::Orientation GetOrientation() const override;
+
+    void CalculateLogicalInsertPosition (
+        const Point& rModelPosition,
+        InsertPosition& rPosition) const override;
+
+protected:
+    virtual void CalculateRowAndColumnCount (const Size& rWindowSize) override;
+    virtual void CalculateMaxRowAndColumnCount (const Size& rWindowSize) override;
+    virtual Size CalculateTargetSize (
+        const Size& rWindowSize) const override;
+};
+
+/** The number of columns of the grid layouter is defined via a control in
+    the slide sorter tool bar.  The number of rows is calculated from the
+    number of columns and the number of pages.
+*/
+class GridImplementation : public Layouter::Implementation
+{
+public:
+    GridImplementation (
+        sd::Window *pWindow,
+        const std::shared_ptr<view::Theme>& rpTheme);
+    explicit GridImplementation(const Implementation& rImplementation);
+
+    virtual Layouter::Orientation GetOrientation() const override;
+
+    void CalculateLogicalInsertPosition (
+        const Point& rModelPosition,
+        InsertPosition& rPosition) const override;
+
+protected:
+    virtual void CalculateRowAndColumnCount (const Size& rWindowSize) override;
+    virtual void CalculateMaxRowAndColumnCount (const Size& rWindowSize) override;
+    virtual Size CalculateTargetSize (
+        const Size& rWindowSize) const override;
+};
+
+}
+
+//===== Layouter ==============================================================
+
+Layouter::Layouter (
+    sd::Window *pWindow,
+    const std::shared_ptr<Theme>& rpTheme)
+    : mpImplementation(new GridImplementation(pWindow, rpTheme)),
+      mpWindow(pWindow)
+{
+}
+
+Layouter::~Layouter()
+{
+}
+
+std::shared_ptr<PageObjectLayouter> const & Layouter::GetPageObjectLayouter() const
+{
+    return mpImplementation->mpPageObjectLayouter;
+}
+
+void Layouter::SetColumnCount (
+    sal_Int32 nMinimalColumnCount,
+        sal_Int32 nMaximalColumnCount)
+{
+    if (nMinimalColumnCount <= nMaximalColumnCount)
+    {
+        mpImplementation->mnMinimalColumnCount = nMinimalColumnCount;
+        mpImplementation->mnMaximalColumnCount = nMaximalColumnCount;
+    }
+}
+
+bool Layouter::Rearrange (
+    const Orientation eOrientation,
+    const Size& rWindowSize,
+    const Size& rPageSize,
+    const sal_uInt32 nPageCount)
+{
+    OSL_ASSERT(mpWindow);
+
+    if (eOrientation != mpImplementation->GetOrientation())
+        mpImplementation.reset(Implementation::Create(*mpImplementation, eOrientation));
+
+    return mpImplementation->Rearrange(rWindowSize, rPageSize, nPageCount);
+}
+
+sal_Int32 Layouter::GetColumnCount() const
+{
+    return mpImplementation->mnColumnCount;
+}
+
+sal_Int32 Layouter::GetIndex (const sal_Int32 nRow, const sal_Int32 nColumn) const
+{
+    return mpImplementation->GetIndex(nRow,nColumn,true);
+}
+
+Size const & Layouter::GetPageObjectSize() const
+{
+    return mpImplementation->maPageObjectSize;
+}
+
+::tools::Rectangle Layouter::GetPageObjectBox (
+    const sal_Int32 nIndex,
+    const bool bIncludeBorderAndGap) const
+{
+    return mpImplementation->GetPageObjectBox(nIndex, bIncludeBorderAndGap);
+}
+
+::tools::Rectangle Layouter::GetTotalBoundingBox() const
+{
+    return mpImplementation->GetTotalBoundingBox();
+}
+
+InsertPosition Layouter::GetInsertPosition (
+    const Point& rModelPosition,
+    const Size& rIndicatorSize,
+    model::SlideSorterModel const & rModel) const
+{
+    InsertPosition aPosition;
+    mpImplementation->CalculateLogicalInsertPosition(
+        rModelPosition,
+        aPosition);
+    mpImplementation->CalculateGeometricPosition(
+        aPosition,
+        rIndicatorSize,
+        GetColumnCount()==1,
+        rModel);
+    return aPosition;
+}
+
+Range Layouter::GetValidHorizontalSizeRange() const
+{
+    return mpImplementation->GetValidHorizontalSizeRange();
+}
+
+Range Layouter::GetValidVerticalSizeRange() const
+{
+    return mpImplementation->GetValidVerticalSizeRange();
+}
+
+Range Layouter::GetRangeOfVisiblePageObjects (const ::tools::Rectangle& aVisibleArea) const
+{
+    return mpImplementation->GetRangeOfVisiblePageObjects(aVisibleArea);
+}
+
+sal_Int32 Layouter::GetIndexAtPoint (
+    const Point& rPosition,
+    const bool bIncludePageBorders,
+    const bool bClampToValidRange) const
+{
+    const sal_Int32 nRow (
+        mpImplementation->GetRowAtPosition (
+            rPosition.Y(),
+            bIncludePageBorders,
+            bIncludePageBorders ? Implementation::GM_PAGE_BORDER : Implementation::GM_NONE));
+    const sal_Int32 nColumn (
+        mpImplementation->GetColumnAtPosition (
+            rPosition.X(),
+            bIncludePageBorders,
+            bIncludePageBorders ? Implementation::GM_PAGE_BORDER : Implementation::GM_NONE));
+
+    return mpImplementation->GetIndex(nRow,nColumn,bClampToValidRange);
+}
+
+//===== Layouter::Implementation ==============================================
+
+Layouter::Implementation* Layouter::Implementation::Create (
+    const Implementation& rImplementation,
+    const Layouter::Orientation eOrientation)
+{
+    switch (eOrientation)
+    {
+        case HORIZONTAL: return new HorizontalImplementation(rImplementation);
+        case VERTICAL: return new VerticalImplementation(rImplementation);
+        case GRID:
+        default: return new GridImplementation(rImplementation);
+    }
+}
+
+Layouter::Implementation::Implementation (
+    sd::Window *pWindow,
+    const std::shared_ptr<view::Theme>& rpTheme)
+    : mpWindow(pWindow),
+      mnLeftBorder(5),
+      mnRightBorder(5),
+      mnTopBorder(5),
+      mnBottomBorder(5),
+      maMinimalSize(132,98),
+      maPreferredSize(200,150),
+      maMaximalSize(600,400),
+      mnMinimalColumnCount(1),
+      mnMaximalColumnCount(15),
+      mnPageCount(0),
+      mnColumnCount(1),
+      mnRowCount(0),
+      mnMaxColumnCount(0),
+      mnMaxRowCount(0),
+      maPageObjectSize(1,1),
+      mpTheme(rpTheme)
+{
+}
+
+Layouter::Implementation::Implementation (const Implementation& rImplementation)
+    : mpWindow(rImplementation.mpWindow),
+      mnLeftBorder(rImplementation.mnLeftBorder),
+      mnRightBorder(rImplementation.mnRightBorder),
+      mnTopBorder(rImplementation.mnTopBorder),
+      mnBottomBorder(rImplementation.mnBottomBorder),
+      maMinimalSize(rImplementation.maMinimalSize),
+      maPreferredSize(rImplementation.maPreferredSize),
+      maMaximalSize(rImplementation.maMaximalSize),
+      mnMinimalColumnCount(rImplementation.mnMinimalColumnCount),
+      mnMaximalColumnCount(rImplementation.mnMaximalColumnCount),
+      mnPageCount(rImplementation.mnPageCount),
+      mnColumnCount(rImplementation.mnColumnCount),
+      mnRowCount(rImplementation.mnRowCount),
+      mnMaxColumnCount(rImplementation.mnMaxColumnCount),
+      mnMaxRowCount(rImplementation.mnMaxRowCount),
+      maPageObjectSize(rImplementation.maPageObjectSize),
+      mpTheme(rImplementation.mpTheme)
+{
+}
+
+Layouter::Implementation::~Implementation()
+{
+}
+
+bool Layouter::Implementation::Rearrange (
+    const Size& rWindowSize,
+    const Size& rPreviewModelSize,
+    const sal_uInt32 nPageCount)
+{
+    mnPageCount = nPageCount;
+
+    // Return early when the window or the model have not yet been initialized.
+    if (rWindowSize.IsEmpty())
+        return false;
+    if (rPreviewModelSize.IsEmpty())
+        return false;
+
+    CalculateRowAndColumnCount(rWindowSize);
+
+    // Update the border values.
+    mnLeftBorder = mnRequestedLeftBorder;
+    mnTopBorder = mnRequestedTopBorder;
+    mnRightBorder = mnRequestedRightBorder;
+    mnBottomBorder = mnRequestedBottomBorder;
+    if (mnColumnCount > 1)
+    {
+        int nMinimumBorderWidth = gnHorizontalGap/2;
+        if (mnLeftBorder < nMinimumBorderWidth)
+            mnLeftBorder = nMinimumBorderWidth;
+        if (mnRightBorder < nMinimumBorderWidth)
+            mnRightBorder = nMinimumBorderWidth;
+    }
+    else
+    {
+        int nMinimumBorderHeight = gnVerticalGap/2;
+        if (mnTopBorder < nMinimumBorderHeight)
+            mnTopBorder = nMinimumBorderHeight;
+        if (mnBottomBorder < nMinimumBorderHeight)
+            mnBottomBorder = nMinimumBorderHeight;
+    }
+
+    mpPageObjectLayouter =
+        std::make_shared<PageObjectLayouter>(
+            CalculateTargetSize(rWindowSize),
+            rPreviewModelSize,
+            mpWindow,
+            mnPageCount);
+
+    maPageObjectSize = mpPageObjectLayouter->GetGridMaxSize();
+
+    CalculateMaxRowAndColumnCount(rWindowSize);
+
+    return true;
+}
+
+sal_Int32 Layouter::Implementation::GetRowAtPosition (
+    sal_Int32 nYPosition,
+    bool bIncludeBordersAndGaps,
+    GapMembership eGapMembership) const
+{
+    sal_Int32 nRow = -1;
+
+    const sal_Int32 nY = nYPosition - mnTopBorder;
+    if (nY >= 0)
+    {
+        // Vertical distance from one row to the next.
+        const sal_Int32 nRowOffset (maPageObjectSize.Height() + gnVerticalGap);
+
+        // Calculate row consisting of page objects and gap below.
+        nRow = nY / nRowOffset;
+
+        const sal_Int32 nDistanceIntoGap ((nY - nRow*nRowOffset) - maPageObjectSize.Height());
+        // When inside the gap below then nYPosition is not over a page
+        // object.
+        if (nDistanceIntoGap > 0)
+        {
+            sal_Int32 nResolvedRow = ResolvePositionInGap(
+                nDistanceIntoGap,
+                eGapMembership,
+                nRow,
+                gnVerticalGap);
+            if (!bIncludeBordersAndGaps || nResolvedRow != -1)
+                nRow = nResolvedRow;
+        }
+    }
+    else if (bIncludeBordersAndGaps)
+    {
+        // We are in the top border area.  Set nRow to the first row when
+        // the top border shall be considered to belong to the first row.
+        nRow = 0;
+    }
+
+    return nRow;
+}
+
+sal_Int32 Layouter::Implementation::GetColumnAtPosition (
+    sal_Int32 nXPosition,
+    bool bIncludeBordersAndGaps,
+    GapMembership eGapMembership) const
+{
+    sal_Int32 nColumn = -1;
+
+    sal_Int32 nX = nXPosition - mnLeftBorder;
+    if (nX >= 0)
+    {
+        // Horizontal distance from one column to the next.
+        const sal_Int32 nColumnOffset (maPageObjectSize.Width() + gnHorizontalGap);
+
+        // Calculate row consisting of page objects and gap below.
+        nColumn = nX / nColumnOffset;
+        if (nColumn < 0)
+            nColumn = 0;
+        else if (nColumn >= mnColumnCount)
+            nColumn = mnColumnCount-1;
+
+        const sal_Int32 nDistanceIntoGap ((nX - nColumn*nColumnOffset) - maPageObjectSize.Width());
+        // When inside the gap at the right then nXPosition is not over a
+        // page object.
+        if (nDistanceIntoGap > 0)
+        {
+            sal_Int32 nResolvedColumn = ResolvePositionInGap(
+                nDistanceIntoGap,
+                eGapMembership,
+                nColumn,
+                gnHorizontalGap);
+            if (!bIncludeBordersAndGaps || nResolvedColumn != -1)
+                nColumn = nResolvedColumn;
+        }
+    }
+    else if (bIncludeBordersAndGaps)
+    {
+        // We are in the left border area.  Set nColumn to the first column
+        // when the left border shall be considered to belong to the first
+        // column.
+        nColumn = 0;
+    }
+    return nColumn;
+}
+
+sal_Int32 Layouter::Implementation::ResolvePositionInGap (
+    sal_Int32 nDistanceIntoGap,
+    GapMembership eGapMembership,
+    sal_Int32 nIndex,
+    sal_Int32 nGap)
+{
+    switch (eGapMembership)
+    {
+        case GM_NONE:
+            // The gap is no man's land.
+            nIndex = -1;
+            break;
+
+        case GM_BOTH:
+        {
+            // The lower half of the gap belongs to the next row or column.
+            sal_Int32 nFirstHalfGapWidth = nGap / 2;
+            if (nDistanceIntoGap > nFirstHalfGapWidth)
+                nIndex ++;
+            break;
+        }
+
+        case GM_PREVIOUS:
+            // Row or column already at correct value.
+            break;
+
+        case GM_NEXT:
+            // The complete gap belongs to the next row or column.
+            nIndex ++;
+            break;
+
+        case GM_PAGE_BORDER:
+            if (nDistanceIntoGap > 0)
+            {
+                if (nDistanceIntoGap > nGap)
+                {
+                    // Inside the border of the next row or column.
+                    nIndex ++;
+                }
+                else
+                {
+                    // Inside the gap between the page borders.
+                    nIndex = -1;
+                }
+            }
+            break;
+
+        default:
+            nIndex = -1;
+    }
+
+    return nIndex;
+}
+
+void Layouter::Implementation::CalculateGeometricPosition (
+    InsertPosition& rPosition,
+    const Size& rIndicatorSize,
+    const bool bIsVertical,
+    model::SlideSorterModel const & rModel) const
+{
+    // 1. Determine right/bottom of the leading page and the left/top of the
+    // trailing page object and how to distribute the missing space.
+    sal_Int32 nLeadingLocation (0);
+    sal_Int32 nTrailingLocation (0);
+    bool bIsLeadingFixed (false);
+    bool bIsTrailingFixed (false);
+    sal_Int32 nSecondaryLocation (0);
+    const sal_Int32 nIndex (rPosition.GetIndex());
+
+    if (rPosition.IsAtRunStart())
+    {
+        // Place indicator at the top of the column.
+        const ::tools::Rectangle aOuterBox (GetPageObjectBox(nIndex));
+        const ::tools::Rectangle aInnerBox (GetInnerBoundingBox(rModel, nIndex));
+        if (bIsVertical)
+        {
+            nLeadingLocation = aOuterBox.Top();
+            nTrailingLocation = aInnerBox.Top();
+            nSecondaryLocation = aInnerBox.Center().X();
+        }
+        else
+        {
+            nLeadingLocation = aOuterBox.Left();
+            nTrailingLocation = aInnerBox.Left();
+            nSecondaryLocation = aInnerBox.Center().Y();
+        }
+        bIsLeadingFixed = true;
+    }
+    else if (rPosition.IsAtRunEnd())
+    {
+        // Place indicator at the bottom/right of the column/row.
+
+        const ::tools::Rectangle aOuterBox (GetPageObjectBox(nIndex-1));
+        const ::tools::Rectangle aInnerBox (GetInnerBoundingBox(rModel, nIndex-1));
+        if (bIsVertical)
+        {
+            nLeadingLocation = aInnerBox.Bottom();
+            nTrailingLocation = aOuterBox.Bottom();
+            nSecondaryLocation = aInnerBox.Center().X();
+        }
+        else
+        {
+            nLeadingLocation = aInnerBox.Right();
+            nTrailingLocation = aOuterBox.Right();
+            nSecondaryLocation = aInnerBox.Center().Y();
+        }
+        bIsTrailingFixed = true;
+        if ( ! rPosition.IsExtraSpaceNeeded())
+            bIsLeadingFixed = true;
+    }
+    else
+    {
+        // Place indicator between two rows/columns.
+        const ::tools::Rectangle aBox1 (GetInnerBoundingBox(rModel, nIndex-1));
+        const ::tools::Rectangle aBox2 (GetInnerBoundingBox(rModel, nIndex));
+        if (bIsVertical)
+        {
+            nLeadingLocation = aBox1.Bottom();
+            nTrailingLocation = aBox2.Top();
+            nSecondaryLocation = (aBox1.Center().X() + aBox2.Center().X()) / 2;
+        }
+        else
+        {
+            nLeadingLocation = aBox1.Right();
+            nTrailingLocation = aBox2.Left();
+            nSecondaryLocation = (aBox1.Center().Y() + aBox2.Center().Y()) / 2;
+        }
+    }
+
+    // 2. Calculate the location of the insert indicator and the offsets of
+    // leading and trailing pages.
+    const sal_Int32 nAvailableSpace (nTrailingLocation - nLeadingLocation);
+    const sal_Int32 nRequiredSpace (bIsVertical ? rIndicatorSize.Height():rIndicatorSize.Width());
+    const sal_Int32 nMissingSpace (::std::max(sal_Int32(0), nRequiredSpace - nAvailableSpace));
+    sal_Int32 nPrimaryLocation (0);
+    sal_Int32 nLeadingOffset (0);
+    sal_Int32 nTrailingOffset (0);
+    if (bIsLeadingFixed)
+    {
+        nPrimaryLocation = nLeadingLocation + nRequiredSpace/2;
+        if ( ! bIsTrailingFixed)
+            nTrailingOffset = nMissingSpace;
+    }
+    else if (bIsTrailingFixed)
+    {
+        nPrimaryLocation = nTrailingLocation - nRequiredSpace/2;
+        nLeadingOffset = -nMissingSpace;
+    }
+    else
+    {
+        nPrimaryLocation = (nLeadingLocation + nTrailingLocation) /2;
+        nLeadingOffset = -nMissingSpace/2;
+        nTrailingOffset = nMissingSpace + nLeadingOffset;
+    }
+
+    if (bIsVertical)
+    {
+        rPosition.SetGeometricalPosition(
+            Point(nSecondaryLocation, nPrimaryLocation),
+            Point(0, nLeadingOffset),
+            Point(0, nTrailingOffset));
+    }
+    else
+    {
+        rPosition.SetGeometricalPosition(
+            Point(nPrimaryLocation, nSecondaryLocation),
+            Point(nLeadingOffset, 0),
+            Point(nTrailingOffset, 0));
+    }
+}
+
+::tools::Rectangle Layouter::Implementation::GetInnerBoundingBox (
+    model::SlideSorterModel const & rModel,
+    const sal_Int32 nIndex) const
+{
+    model::SharedPageDescriptor pDescriptor (rModel.GetPageDescriptor(nIndex));
+    if ( ! pDescriptor)
+        return ::tools::Rectangle();
+
+    PageObjectLayouter::Part ePart = PageObjectLayouter::Part::Preview;
+
+    if (pDescriptor->HasState(model::PageDescriptor::ST_Selected))
+        ePart = PageObjectLayouter::Part::PageObject;
+
+    return mpPageObjectLayouter->GetBoundingBox(
+            pDescriptor, ePart,
+            PageObjectLayouter::ModelCoordinateSystem, true);
+}
+
+Range Layouter::Implementation::GetValidHorizontalSizeRange() const
+{
+    return Range(
+        mnLeftBorder + maMinimalSize.Width() + mnRightBorder,
+        mnLeftBorder + maMaximalSize.Width() + mnRightBorder);
+}
+
+Range Layouter::Implementation::GetValidVerticalSizeRange() const
+{
+    return Range(
+        mnTopBorder + maMinimalSize.Height() + mnBottomBorder,
+        mnTopBorder + maMaximalSize.Height() + mnBottomBorder);
+}
+
+Range Layouter::Implementation::GetRangeOfVisiblePageObjects (const ::tools::Rectangle& aVisibleArea) const
+{
+    // technically that's not empty, but it's the default, so...
+    if (aVisibleArea.IsEmpty())
+        return Range(-1, -1);
+
+    const sal_Int32 nRow0 (GetRowAtPosition(aVisibleArea.Top(), true, GM_NEXT));
+    const sal_Int32 nCol0 (GetColumnAtPosition(aVisibleArea.Left(),true, GM_NEXT));
+    const sal_Int32 nRow1 (GetRowAtPosition(aVisibleArea.Bottom(), true, GM_PREVIOUS));
+    const sal_Int32 nCol1 (GetColumnAtPosition(aVisibleArea.Right(), true, GM_PREVIOUS));
+
+    // When start and end lie in different rows then the range may include
+    // slides outside (left or right of) the given area.
+    return Range(GetIndex(nRow0,nCol0,true), GetIndex(nRow1,nCol1,true));
+}
+
+Size Layouter::Implementation::GetTargetSize (
+    const Size& rWindowSize,
+    const bool bCalculateWidth,
+    const bool bCalculateHeight) const
+{
+    if (mnColumnCount<=0 || mnRowCount<=0)
+        return maPreferredSize;
+    if ( ! (bCalculateWidth || bCalculateHeight))
+    {
+        OSL_ASSERT(bCalculateWidth || bCalculateHeight);
+        return maPreferredSize;
+    }
+
+    // Calculate the width of each page object.
+    Size aTargetSize (0,0);
+    if (bCalculateWidth)
+        aTargetSize.setWidth(
+            (rWindowSize.Width() - mnLeftBorder - mnRightBorder
+                - (mnColumnCount-1) * gnHorizontalGap)
+                    / mnColumnCount);
+    else if (bCalculateHeight)
+        aTargetSize.setHeight(
+            (rWindowSize.Height() - mnTopBorder - mnBottomBorder
+                - (mnRowCount-1) * gnVerticalGap)
+                    / mnRowCount);
+
+    if (bCalculateWidth)
+    {
+        if (aTargetSize.Width() < maMinimalSize.Width())
+            aTargetSize.setWidth(maMinimalSize.Width());
+        else if (aTargetSize.Width() > maMaximalSize.Width())
+            aTargetSize.setWidth(maMaximalSize.Width());
+    }
+    else if (bCalculateHeight)
+    {
+        if (aTargetSize.Height() < maMinimalSize.Height())
+            aTargetSize.setHeight(maMinimalSize.Height());
+        else if (aTargetSize.Height() > maMaximalSize.Height())
+            aTargetSize.setHeight(maMaximalSize.Height());
+    }
+
+    return aTargetSize;
+}
+
+sal_Int32 Layouter::Implementation::GetIndex (
+    const sal_Int32 nRow,
+    const sal_Int32 nColumn,
+    const bool bClampToValidRange) const
+{
+    if (nRow >= 0 && nColumn >= 0)
+    {
+        const sal_Int32 nIndex (nRow * mnColumnCount + nColumn);
+        if (nIndex >= mnPageCount)
+            if (bClampToValidRange)
+                return mnPageCount-1;
+            else
+                return -1;
+        else
+            return nIndex;
+    }
+    else if (bClampToValidRange)
+        return 0;
+    else
+        return -1;
+}
+
+::tools::Rectangle Layouter::Implementation::GetPageObjectBox (
+    const sal_Int32 nIndex,
+    const bool bIncludeBorderAndGap) const
+{
+    const sal_Int32 nRow (nIndex / mnColumnCount);
+    const sal_Int32 nColumn (nIndex % mnColumnCount);
+
+    const ::tools::Rectangle aBoundingBox (GetPageObjectBox(nRow,nColumn));
+    if (bIncludeBorderAndGap)
+        return AddBorderAndGap(aBoundingBox, nRow, nColumn);
+    else
+        return aBoundingBox;
+}
+
+::tools::Rectangle Layouter::Implementation::GetPageObjectBox (
+    const sal_Int32 nRow,
+    const sal_Int32 nColumn) const
+{
+    return ::tools::Rectangle(
+        Point (mnLeftBorder
+            + nColumn * maPageObjectSize.Width()
+            + std::max<sal_Int32>(nColumn,0) * gnHorizontalGap,
+            mnTopBorder
+            + nRow * maPageObjectSize.Height()
+            + std::max<sal_Int32>(nRow,0) * gnVerticalGap),
+        maPageObjectSize);
+}
+
+::tools::Rectangle Layouter::Implementation::AddBorderAndGap (
+    const ::tools::Rectangle& rBoundingBox,
+    const sal_Int32 nRow,
+    const sal_Int32 nColumn) const
+{
+    ::tools::Rectangle aBoundingBox (rBoundingBox);
+
+    if (nColumn == 0)
+        aBoundingBox.SetLeft( 0 );
+    else
+        aBoundingBox.AdjustLeft( -(gnHorizontalGap/2) );
+    if (nColumn == mnColumnCount-1)
+        aBoundingBox.AdjustRight(mnRightBorder );
+    else
+        aBoundingBox.AdjustRight(gnHorizontalGap/2 );
+    if (nRow == 0)
+        aBoundingBox.SetTop( 0 );
+    else
+        aBoundingBox.AdjustTop( -(gnVerticalGap/2) );
+    if (nRow == mnRowCount-1)
+        aBoundingBox.AdjustBottom(mnBottomBorder );
+    else
+        aBoundingBox.AdjustBottom(gnVerticalGap/2 );
+    return aBoundingBox;
+}
+
+::tools::Rectangle Layouter::Implementation::GetTotalBoundingBox() const
+{
+    sal_Int32 nHorizontalSize = 0;
+    sal_Int32 nVerticalSize = 0;
+    if (mnColumnCount > 0)
+    {
+        sal_Int32 nRowCount = (mnPageCount+mnColumnCount-1) / mnColumnCount;
+        nHorizontalSize =
+            mnLeftBorder
+            + mnRightBorder
+            + mnColumnCount * maPageObjectSize.Width();
+        if (mnColumnCount > 1)
+            nHorizontalSize +=  (mnColumnCount-1) * gnHorizontalGap;
+        nVerticalSize =
+            mnTopBorder
+            + mnBottomBorder
+            + nRowCount * maPageObjectSize.Height();
+        if (nRowCount > 1)
+            nVerticalSize += (nRowCount-1) * gnVerticalGap;
+    }
+
+    return ::tools::Rectangle (
+        Point(0,0),
+        Size (nHorizontalSize, nVerticalSize)
+        );
+}
+
+void Layouter::Implementation::CalculateVerticalLogicalInsertPosition (
+    const Point& rModelPosition,
+    InsertPosition& rPosition) const
+{
+    const sal_Int32 nY = rModelPosition.Y() - mnTopBorder + maPageObjectSize.Height()/2;
+    const sal_Int32 nRowHeight (maPageObjectSize.Height() + gnVerticalGap);
+    const sal_Int32 nRow (::std::min(mnPageCount, nY / nRowHeight));
+    rPosition.SetLogicalPosition (
+        nRow,
+        0,
+        nRow,
+        (nRow == 0),
+        (nRow == mnRowCount),
+        (nRow >= mnMaxRowCount));
+}
+
+//===== HorizontalImplementation ================================================
+
+HorizontalImplementation::HorizontalImplementation (const Implementation& rImplementation)
+    : Implementation(rImplementation)
+{
+}
+
+Layouter::Orientation HorizontalImplementation::GetOrientation() const
+{
+    return Layouter::HORIZONTAL;
+}
+
+void HorizontalImplementation::CalculateRowAndColumnCount (const Size&)
+{
+    // Row and column count are fixed (for a given page count.)
+    mnColumnCount = mnPageCount;
+    mnRowCount = 1;
+}
+
+void HorizontalImplementation::CalculateMaxRowAndColumnCount (const Size& rWindowSize)
+{
+    mnMaxColumnCount = (rWindowSize.Width() - mnLeftBorder - mnRightBorder)
+        / (maPageObjectSize.Width()  + gnHorizontalGap);
+    mnMaxRowCount = 1;
+}
+
+Size HorizontalImplementation::CalculateTargetSize (
+    const Size& rWindowSize) const
+{
+    return Implementation::GetTargetSize(rWindowSize, false, true);
+}
+
+void HorizontalImplementation::CalculateLogicalInsertPosition (
+    const Point& rModelPosition,
+    InsertPosition& rPosition) const
+{
+    const sal_Int32 nX = rModelPosition.X() - mnLeftBorder + maPageObjectSize.Width()/2;
+    const sal_Int32 nColumnWidth (maPageObjectSize.Width() + gnHorizontalGap);
+    const sal_Int32 nColumn (::std::min(mnPageCount, nX / nColumnWidth));
+    rPosition.SetLogicalPosition (
+        0,
+        nColumn,
+        nColumn,
+        (nColumn == 0),
+        (nColumn == mnColumnCount),
+        (nColumn >= mnMaxColumnCount));
+}
+
+//===== VerticalImplementation ================================================
+
+VerticalImplementation::VerticalImplementation (const Implementation& rImplementation)
+    : Implementation(rImplementation)
+{
+}
+
+Layouter::Orientation VerticalImplementation::GetOrientation() const
+{
+    return Layouter::VERTICAL;
+}
+
+void VerticalImplementation::CalculateRowAndColumnCount (const Size&)
+{
+    // Row and column count are fixed (for a given page count.)
+    mnRowCount = mnPageCount;
+    mnColumnCount = 1;
+
+}
+
+void VerticalImplementation::CalculateMaxRowAndColumnCount (const Size& rWindowSize)
+{
+    mnMaxRowCount = (rWindowSize.Height() - mnTopBorder - mnBottomBorder)
+        / (maPageObjectSize.Height()  + gnVerticalGap);
+    mnMaxColumnCount = 1;
+}
+
+Size VerticalImplementation::CalculateTargetSize (
+    const Size& rWindowSize) const
+{
+    return Implementation::GetTargetSize(rWindowSize, true, false);
+}
+
+void VerticalImplementation::CalculateLogicalInsertPosition (
+    const Point& rModelPosition,
+    InsertPosition& rPosition) const
+{
+    return CalculateVerticalLogicalInsertPosition(rModelPosition, rPosition);
+}
+
+//===== GridImplementation ================================================
+
+GridImplementation::GridImplementation (
+    sd::Window *pWindow,
+    const std::shared_ptr<view::Theme>& rpTheme)
+    : Implementation(pWindow, rpTheme)
+{
+}
+
+GridImplementation::GridImplementation (const Implementation& rImplementation)
+    : Implementation(rImplementation)
+{
+}
+
+Layouter::Orientation GridImplementation::GetOrientation() const
+{
+    return Layouter::GRID;
+}
+
+void GridImplementation::CalculateRowAndColumnCount (const Size& rWindowSize)
+{
+    // Calculate the column count.
+    mnColumnCount
+        = (rWindowSize.Width() - mnRequestedLeftBorder - mnRequestedRightBorder)
+        / (maPreferredSize.Width()  + gnHorizontalGap);
+    if (mnColumnCount < mnMinimalColumnCount)
+        mnColumnCount = mnMinimalColumnCount;
+    if (mnColumnCount > mnMaximalColumnCount)
+        mnColumnCount = mnMaximalColumnCount;
+    mnRowCount = (mnPageCount + mnColumnCount-1)/mnColumnCount;
+}
+
+void GridImplementation::CalculateMaxRowAndColumnCount (const Size& rWindowSize)
+{
+    mnMaxColumnCount = (rWindowSize.Width() - mnLeftBorder - mnRightBorder)
+        / (maPageObjectSize.Width()  + gnHorizontalGap);
+    mnMaxRowCount = (rWindowSize.Height() - mnTopBorder - mnBottomBorder)
+        / (maPageObjectSize.Height()  + gnVerticalGap);
+}
+
+Size GridImplementation::CalculateTargetSize (
+    const Size& rWindowSize) const
+{
+    return Implementation::GetTargetSize(rWindowSize, true, true);
+}
+
+void GridImplementation::CalculateLogicalInsertPosition (
+    const Point& rModelPosition,
+    InsertPosition& rPosition) const
+{
+    if (mnColumnCount == 1)
+    {
+        CalculateVerticalLogicalInsertPosition(rModelPosition, rPosition);
+    }
+    else
+    {
+        // Handle the general case of more than one column.
+        sal_Int32 nRow (::std::min(
+            mnRowCount-1,
+            GetRowAtPosition (rModelPosition.Y(), true, GM_BOTH)));
+        const sal_Int32 nX = rModelPosition.X() - mnLeftBorder + maPageObjectSize.Width()/2;
+        const sal_Int32 nColumnWidth (maPageObjectSize.Width() + gnHorizontalGap);
+        sal_Int32 nColumn (::std::min(mnColumnCount, nX / nColumnWidth));
+        sal_Int32 nIndex (nRow * mnColumnCount + nColumn);
+        bool bIsAtRunEnd (nColumn == mnColumnCount);
+
+        if (nIndex >= mnPageCount)
+        {
+            nIndex = mnPageCount;
+            nRow = mnRowCount-1;
+            nColumn = ::std::min(::std::min(mnPageCount, mnColumnCount), nColumn);
+            bIsAtRunEnd = true;
+        }
+
+        rPosition.SetLogicalPosition (
+            nRow,
+            nColumn,
+            nIndex,
+            (nColumn == 0),
+            bIsAtRunEnd,
+            (nColumn >= mnMaxColumnCount));
+    }
+}
+
+//===== InsertPosition ========================================================
+
+InsertPosition::InsertPosition()
+    : mnRow(-1),
+      mnColumn(-1),
+      mnIndex(-1),
+      mbIsAtRunStart(false),
+      mbIsAtRunEnd(false),
+      mbIsExtraSpaceNeeded(false),
+      maLocation(0,0),
+      maLeadingOffset(0,0),
+      maTrailingOffset(0,0)
+{
+}
+
+bool InsertPosition::operator== (const InsertPosition& rInsertPosition) const
+{
+    // Do not compare the geometrical information (maLocation).
+    return mnRow==rInsertPosition.mnRow
+        && mnColumn==rInsertPosition.mnColumn
+        && mnIndex==rInsertPosition.mnIndex
+        && mbIsAtRunStart==rInsertPosition.mbIsAtRunStart
+        && mbIsAtRunEnd==rInsertPosition.mbIsAtRunEnd
+        && mbIsExtraSpaceNeeded==rInsertPosition.mbIsExtraSpaceNeeded;
+}
+
+bool InsertPosition::operator!= (const InsertPosition& rInsertPosition) const
+{
+    return !operator==(rInsertPosition);
+}
+
+void InsertPosition::SetLogicalPosition (
+    const sal_Int32 nRow,
+    const sal_Int32 nColumn,
+    const sal_Int32 nIndex,
+    const bool bIsAtRunStart,
+    const bool bIsAtRunEnd,
+    const bool bIsExtraSpaceNeeded)
+{
+    mnRow = nRow;
+    mnColumn = nColumn;
+    mnIndex = nIndex;
+    mbIsAtRunStart = bIsAtRunStart;
+    mbIsAtRunEnd = bIsAtRunEnd;
+    mbIsExtraSpaceNeeded = bIsExtraSpaceNeeded;
+}
+
+void InsertPosition::SetGeometricalPosition(
+    const Point& rLocation,
+    const Point& rLeadingOffset,
+    const Point& rTrailingOffset)
+{
+    maLocation = rLocation;
+    maLeadingOffset = rLeadingOffset;
+    maTrailingOffset = rTrailingOffset;
+}
+
+} // end of namespace ::sd::slidesorter::namespace
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/view/SlsPageObjectLayouter.cxx b/sd/source/ui/slidesorter/view/SlsPageObjectLayouter.cxx
new file mode 100644
index 000000000..b26eb0746
--- /dev/null
+++ b/sd/source/ui/slidesorter/view/SlsPageObjectLayouter.cxx
@@ -0,0 +1,259 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <view/SlsPageObjectLayouter.hxx>
+
+#include <model/SlsPageDescriptor.hxx>
+#include <view/SlsTheme.hxx>
+#include <tools/IconCache.hxx>
+#include <Window.hxx>
+
+#include <bitmaps.hlst>
+#include <osl/diagnose.h>
+
+namespace sd::slidesorter::view {
+
+namespace {
+const sal_Int32 gnLeftPageNumberOffset = 2;
+const sal_Int32 gnRightPageNumberOffset = 5;
+const sal_Int32 gnOuterBorderWidth = 5;
+const sal_Int32 gnInfoAreaMinWidth = 26;
+}
+
+PageObjectLayouter::PageObjectLayouter (
+    const Size& rPageObjectWindowSize,
+    const Size& rPageSize,
+    sd::Window *pWindow,
+    const sal_Int32 nPageCount)
+    : mpWindow(pWindow),
+      maTransitionEffectIcon(IconCache::Instance().GetIcon(BMP_FADE_EFFECT_INDICATOR)),
+      maCustomAnimationEffectIcon(IconCache::Instance().GetIcon(BMP_CUSTOM_ANIMATION_INDICATOR)),
+      mpPageNumberFont(Theme::GetFont(Theme::Font_PageNumber, *pWindow->GetOutDev()))
+{
+    const Size aPageNumberAreaSize (GetPageNumberAreaSize(nPageCount));
+
+    const int nMaximumBorderWidth (gnOuterBorderWidth);
+    const int nFocusIndicatorWidth (Theme_FocusIndicatorWidth);
+
+    Size aPageObjectSize(rPageObjectWindowSize.Width(), rPageObjectWindowSize.Height());
+    maPreviewBoundingBox = CalculatePreviewBoundingBox(
+        aPageObjectSize,
+        Size(rPageSize.Width(), rPageSize.Height()),
+        aPageNumberAreaSize.Width(),
+        nFocusIndicatorWidth);
+    maFocusIndicatorBoundingBox = ::tools::Rectangle(Point(0,0), aPageObjectSize);
+    maPageObjectBoundingBox = ::tools::Rectangle(
+        Point(
+            nFocusIndicatorWidth,
+            nFocusIndicatorWidth),
+        Size(
+            aPageObjectSize.Width()-2*nFocusIndicatorWidth,
+            aPageObjectSize.Height()-2*nFocusIndicatorWidth));
+
+    maPageNumberAreaBoundingBox = ::tools::Rectangle(
+        Point(
+            std::max(gnLeftPageNumberOffset,
+                sal_Int32(maPreviewBoundingBox.Left()
+                - gnRightPageNumberOffset
+                - aPageNumberAreaSize.Width())),
+            nMaximumBorderWidth),
+        aPageNumberAreaSize);
+
+    const Size aIconSize (maTransitionEffectIcon.GetSizePixel());
+    maTransitionEffectBoundingBox = ::tools::Rectangle(
+        Point(
+            (maPreviewBoundingBox.Left() - 2*aIconSize.Width()) / 2,
+            maPreviewBoundingBox.Bottom() - aIconSize.Height()),
+        aIconSize);
+    maCustomAnimationEffectBoundingBox = ::tools::Rectangle(
+        Point(
+            (maPreviewBoundingBox.Left() - 2*aIconSize.Width()) / 2,
+            maPreviewBoundingBox.Bottom() - 2*aIconSize.Height()),
+        aIconSize);
+}
+
+PageObjectLayouter::~PageObjectLayouter()
+{
+}
+
+::tools::Rectangle PageObjectLayouter::CalculatePreviewBoundingBox (
+    Size& rPageObjectSize,
+    const Size& rPageSize,
+    const sal_Int32 nPageNumberAreaWidth,
+    const sal_Int32 nFocusIndicatorWidth)
+{
+    const sal_Int32 nIconWidth (maTransitionEffectIcon.GetSizePixel().Width());
+    const sal_Int32 nLeftAreaWidth (
+        ::std::max(
+            gnInfoAreaMinWidth,
+            gnRightPageNumberOffset
+                + ::std::max(
+                    nPageNumberAreaWidth,
+                    nIconWidth)));
+    sal_Int32 nPreviewWidth;
+    sal_Int32 nPreviewHeight;
+    const double nPageAspectRatio (double(rPageSize.Width()) / double(rPageSize.Height()));
+    if (rPageObjectSize.Height() == 0)
+    {
+        // Calculate height so that the preview fills the available
+        // horizontal space completely while observing the aspect ratio of
+        // the preview.
+        nPreviewWidth = rPageObjectSize.Width()
+            - nLeftAreaWidth - gnOuterBorderWidth - 2*nFocusIndicatorWidth - 1;
+        nPreviewHeight = ::basegfx::fround(nPreviewWidth / nPageAspectRatio);
+        rPageObjectSize.setHeight(nPreviewHeight + 2*gnOuterBorderWidth + 2*nFocusIndicatorWidth + 1);
+    }
+    else if (rPageObjectSize.Width() == 0)
+    {
+        // Calculate the width of the page object so that the preview fills
+        // the available vertical space completely while observing the
+        // aspect ratio of the preview.
+        nPreviewHeight = rPageObjectSize.Height() - 2*gnOuterBorderWidth - 2*nFocusIndicatorWidth - 1;
+        nPreviewWidth = ::basegfx::fround(nPreviewHeight * nPageAspectRatio);
+        rPageObjectSize.setWidth(nPreviewWidth
+            + nLeftAreaWidth + gnOuterBorderWidth + 2*nFocusIndicatorWidth + 1);
+
+    }
+    else
+    {
+        // The size of the page object is given.  Calculate the size of the
+        // preview.
+        nPreviewWidth = rPageObjectSize.Width()
+            - nLeftAreaWidth - gnOuterBorderWidth - 2*nFocusIndicatorWidth - 1;
+        nPreviewHeight = rPageObjectSize.Height()
+            - gnOuterBorderWidth - 2*nFocusIndicatorWidth - 1;
+        if (double(nPreviewWidth)/double(nPreviewHeight) > nPageAspectRatio)
+            nPreviewWidth = ::basegfx::fround(nPreviewHeight * nPageAspectRatio);
+        else
+            nPreviewHeight = ::basegfx::fround(nPreviewWidth / nPageAspectRatio);
+    }
+    // When the preview does not fill the available space completely then
+    // place it flush right and vertically centered.
+    const int nLeft (rPageObjectSize.Width()
+        - gnOuterBorderWidth - nPreviewWidth - nFocusIndicatorWidth - 1);
+    const int nTop ((rPageObjectSize.Height() - nPreviewHeight)/2);
+    return ::tools::Rectangle(
+        nLeft,
+        nTop,
+        nLeft + nPreviewWidth,
+        nTop + nPreviewHeight);
+}
+
+::tools::Rectangle PageObjectLayouter::GetBoundingBox (
+    const model::SharedPageDescriptor& rpPageDescriptor,
+    const Part ePart,
+    const CoordinateSystem eCoordinateSystem,
+    bool bIgnoreLocation)
+{
+    OSL_ASSERT(rpPageDescriptor);
+    Point aLocation(0,0);
+    if (rpPageDescriptor)
+        aLocation = rpPageDescriptor->GetLocation( bIgnoreLocation );
+    return GetBoundingBox(aLocation, ePart, eCoordinateSystem);
+}
+
+::tools::Rectangle PageObjectLayouter::GetBoundingBox (
+    const Point& rPageObjectLocation,
+    const Part ePart,
+    const CoordinateSystem eCoordinateSystem)
+{
+    ::tools::Rectangle aBoundingBox;
+    switch (ePart)
+    {
+        case Part::FocusIndicator:
+            aBoundingBox = maFocusIndicatorBoundingBox;
+            break;
+
+        case Part::PageObject:
+            aBoundingBox = maPageObjectBoundingBox;
+            break;
+
+        case Part::Preview:
+            aBoundingBox = maPreviewBoundingBox;
+            break;
+
+        case Part::PageNumber:
+            aBoundingBox = maPageNumberAreaBoundingBox;
+            break;
+
+        case Part::TransitionEffectIndicator:
+            aBoundingBox = maTransitionEffectBoundingBox;
+            break;
+        case Part::CustomAnimationEffectIndicator:
+            aBoundingBox = maCustomAnimationEffectBoundingBox;
+            break;
+    }
+
+    // Adapt coordinates to the requested coordinate system.
+    Point aLocation (rPageObjectLocation);
+    if (eCoordinateSystem == WindowCoordinateSystem)
+        aLocation += mpWindow->GetMapMode().GetOrigin();
+
+    return ::tools::Rectangle(
+        aBoundingBox.TopLeft() + aLocation,
+        aBoundingBox.BottomRight() + aLocation);
+}
+
+Size PageObjectLayouter::GetPreviewSize ()
+{
+    return GetBoundingBox(Point(0,0), PageObjectLayouter::Part::Preview,
+                          WindowCoordinateSystem).GetSize();
+}
+
+Size PageObjectLayouter::GetGridMaxSize()
+{
+    return GetBoundingBox(Point(0,0), PageObjectLayouter::Part::FocusIndicator,
+                          WindowCoordinateSystem).GetSize();
+}
+
+Size PageObjectLayouter::GetPageNumberAreaSize (const int nPageCount)
+{
+    OSL_ASSERT(mpWindow);
+
+    // Set the correct font.
+    vcl::Font aOriginalFont (mpWindow->GetFont());
+    if (mpPageNumberFont)
+        mpWindow->SetFont(*mpPageNumberFont);
+
+    OUString sPageNumberTemplate;
+    if (nPageCount < 10)
+        sPageNumberTemplate = "9";
+    else if (nPageCount < 100)
+        sPageNumberTemplate = "99";
+    else if (nPageCount < 200)
+        // Just for the case that 1 is narrower than 9.
+        sPageNumberTemplate = "199";
+    else if (nPageCount < 1000)
+        sPageNumberTemplate = "999";
+    else
+        sPageNumberTemplate = "9999";
+    // More than 9999 pages are not handled.
+
+    const Size aSize (
+        mpWindow->GetTextWidth(sPageNumberTemplate),
+        mpWindow->GetTextHeight());
+
+    mpWindow->SetFont(aOriginalFont);
+
+    return aSize;
+}
+
+} // end of namespace ::sd::slidesorter::view
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/view/SlsPageObjectPainter.cxx b/sd/source/ui/slidesorter/view/SlsPageObjectPainter.cxx
new file mode 100644
index 000000000..feaf5a5fa
--- /dev/null
+++ b/sd/source/ui/slidesorter/view/SlsPageObjectPainter.cxx
@@ -0,0 +1,442 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <view/SlsPageObjectPainter.hxx>
+
+#include <model/SlsPageDescriptor.hxx>
+#include <view/SlideSorterView.hxx>
+#include <view/SlsPageObjectLayouter.hxx>
+#include <view/SlsLayouter.hxx>
+#include <view/SlsTheme.hxx>
+#include <SlideSorter.hxx>
+#include "SlsFramePainter.hxx"
+#include <cache/SlsPageCache.hxx>
+#include <Window.hxx>
+#include <sdpage.hxx>
+#include <vcl/virdev.hxx>
+#include <CustomAnimationEffect.hxx>
+#include <osl/diagnose.h>
+#include <memory>
+
+using namespace ::drawinglayer::primitive2d;
+
+namespace sd::slidesorter::view {
+
+//===== PageObjectPainter =====================================================
+
+PageObjectPainter::PageObjectPainter (
+    const SlideSorter& rSlideSorter)
+    : mrLayouter(rSlideSorter.GetView().GetLayouter()),
+      mpCache(rSlideSorter.GetView().GetPreviewCache()),
+      mpTheme(rSlideSorter.GetTheme()),
+      mpPageNumberFont(Theme::GetFont(Theme::Font_PageNumber, *rSlideSorter.GetContentWindow()->GetOutDev())),
+      mpShadowPainter(new FramePainter(mpTheme->GetIcon(Theme::Icon_RawShadow))),
+      mpFocusBorderPainter(new FramePainter(mpTheme->GetIcon(Theme::Icon_FocusBorder)))
+{
+    // Replace the color (not the alpha values) in the focus border with a
+    // color derived from the current selection color.
+    Color aColor (mpTheme->GetColor(Theme::Color_Selection));
+    sal_uInt16 nHue, nSat, nBri;
+    aColor.RGBtoHSB(nHue, nSat, nBri);
+    aColor = Color::HSBtoRGB(nHue, 28, 65);
+    mpFocusBorderPainter->AdaptColor(aColor);
+}
+
+PageObjectPainter::~PageObjectPainter()
+{
+}
+
+void PageObjectPainter::PaintPageObject (
+    OutputDevice& rDevice,
+    const model::SharedPageDescriptor& rpDescriptor)
+{
+    if (!UpdatePageObjectLayouter())
+        return;
+
+    PageObjectLayouter *pPageObjectLayouter = mrLayouter.GetPageObjectLayouter().get();
+    // Turn off antialiasing to avoid the bitmaps from being
+    // shifted by fractions of a pixel and thus show blurry edges.
+    const AntialiasingFlags nSavedAntialiasingMode (rDevice.GetAntialiasing());
+    rDevice.SetAntialiasing(nSavedAntialiasingMode & ~AntialiasingFlags::Enable);
+
+    PaintBackground(pPageObjectLayouter, rDevice, rpDescriptor);
+    PaintPreview(pPageObjectLayouter, rDevice, rpDescriptor);
+    PaintPageNumber(pPageObjectLayouter, rDevice, rpDescriptor);
+    PaintTransitionEffect(pPageObjectLayouter, rDevice, rpDescriptor);
+    if (rpDescriptor->GetPage()->hasAnimationNode())
+        PaintCustomAnimationEffect(pPageObjectLayouter, rDevice, rpDescriptor);
+    rDevice.SetAntialiasing(nSavedAntialiasingMode);
+}
+
+bool PageObjectPainter::UpdatePageObjectLayouter()
+{
+    // The page object layouter is quite volatile. It may have been replaced
+    // since the last call.  Update it now.
+    PageObjectLayouter *pPageObjectLayouter = mrLayouter.GetPageObjectLayouter().get();
+    if ( ! pPageObjectLayouter)
+    {
+        OSL_FAIL("no page object layouter");
+        return false;
+    }
+
+    return true;
+}
+
+void PageObjectPainter::SetTheme (const std::shared_ptr<view::Theme>& rpTheme)
+{
+    mpTheme = rpTheme;
+}
+
+void PageObjectPainter::PaintBackground (
+    PageObjectLayouter *pPageObjectLayouter,
+    OutputDevice& rDevice,
+    const model::SharedPageDescriptor& rpDescriptor) const
+{
+    PaintBackgroundDetail(pPageObjectLayouter, rDevice, rpDescriptor);
+
+    // Fill the interior of the preview area with the default background
+    // color of the page.
+    SdPage* pPage = rpDescriptor->GetPage();
+    if (pPage != nullptr)
+    {
+        rDevice.SetFillColor(pPage->GetPageBackgroundColor(nullptr));
+        rDevice.SetLineColor(pPage->GetPageBackgroundColor(nullptr));
+        const ::tools::Rectangle aPreviewBox (pPageObjectLayouter->GetBoundingBox(
+            rpDescriptor,
+            PageObjectLayouter::Part::Preview,
+            PageObjectLayouter::ModelCoordinateSystem));
+        rDevice.DrawRect(aPreviewBox);
+    }
+}
+
+void PageObjectPainter::PaintPreview (
+    PageObjectLayouter *pPageObjectLayouter,
+    OutputDevice& rDevice,
+    const model::SharedPageDescriptor& rpDescriptor) const
+{
+    const ::tools::Rectangle aBox (pPageObjectLayouter->GetBoundingBox(
+        rpDescriptor,
+        PageObjectLayouter::Part::Preview,
+        PageObjectLayouter::ModelCoordinateSystem));
+
+    if (mpCache == nullptr)
+        return;
+
+    const SdrPage* pPage = rpDescriptor->GetPage();
+    mpCache->SetPreciousFlag(pPage, true);
+
+    const BitmapEx aPreview (GetPreviewBitmap(rpDescriptor, &rDevice));
+    if ( ! aPreview.IsEmpty())
+    {
+        if (aPreview.GetSizePixel() != aBox.GetSize())
+            rDevice.DrawBitmapEx(aBox.TopLeft(), aBox.GetSize(), aPreview);
+        else
+            rDevice.DrawBitmapEx(aBox.TopLeft(), aPreview);
+    }
+}
+
+BitmapEx PageObjectPainter::CreateMarkedPreview (
+    const Size& rSize,
+    const BitmapEx& rPreview,
+    const BitmapEx& rOverlay,
+    const OutputDevice* pReferenceDevice)
+{
+    ScopedVclPtr<VirtualDevice> pDevice;
+    if (pReferenceDevice != nullptr)
+        pDevice.disposeAndReset(VclPtr<VirtualDevice>::Create(*pReferenceDevice));
+    else
+        pDevice.disposeAndReset(VclPtr<VirtualDevice>::Create());
+    pDevice->SetOutputSizePixel(rSize);
+
+    pDevice->DrawBitmapEx(Point(0,0), rSize, rPreview);
+
+    // Paint bitmap tiled over the preview to mark it as excluded.
+    const sal_Int32 nIconWidth (rOverlay.GetSizePixel().Width());
+    const sal_Int32 nIconHeight (rOverlay.GetSizePixel().Height());
+    if (nIconWidth>0 && nIconHeight>0)
+    {
+        for (::tools::Long nX=0; nX<rSize.Width(); nX+=nIconWidth)
+            for (::tools::Long nY=0; nY<rSize.Height(); nY+=nIconHeight)
+                pDevice->DrawBitmapEx(Point(nX,nY), rOverlay);
+    }
+    return pDevice->GetBitmapEx(Point(0,0), rSize);
+}
+
+BitmapEx PageObjectPainter::GetPreviewBitmap (
+    const model::SharedPageDescriptor& rpDescriptor,
+    const OutputDevice* pReferenceDevice) const
+{
+    const SdrPage* pPage = rpDescriptor->GetPage();
+    const bool bIsExcluded (rpDescriptor->HasState(model::PageDescriptor::ST_Excluded));
+
+    if (bIsExcluded)
+    {
+        PageObjectLayouter *pPageObjectLayouter = mrLayouter.GetPageObjectLayouter().get();
+
+        BitmapEx aMarkedPreview (mpCache->GetMarkedPreviewBitmap(pPage));
+        const ::tools::Rectangle aPreviewBox (pPageObjectLayouter->GetBoundingBox(
+            rpDescriptor,
+            PageObjectLayouter::Part::Preview,
+            PageObjectLayouter::ModelCoordinateSystem));
+        if (aMarkedPreview.IsEmpty() || aMarkedPreview.GetSizePixel()!=aPreviewBox.GetSize())
+        {
+            aMarkedPreview = CreateMarkedPreview(
+                aPreviewBox.GetSize(),
+                mpCache->GetPreviewBitmap(pPage,true),
+                mpTheme->GetIcon(Theme::Icon_HideSlideOverlay),
+                pReferenceDevice);
+            mpCache->SetMarkedPreviewBitmap(pPage, aMarkedPreview);
+        }
+        return aMarkedPreview;
+    }
+    else
+    {
+        return mpCache->GetPreviewBitmap(pPage,false);
+    }
+}
+
+void PageObjectPainter::PaintPageNumber (
+    PageObjectLayouter *pPageObjectLayouter,
+    OutputDevice& rDevice,
+    const model::SharedPageDescriptor& rpDescriptor) const
+{
+    const ::tools::Rectangle aBox (pPageObjectLayouter->GetBoundingBox(
+        rpDescriptor,
+        PageObjectLayouter::Part::PageNumber,
+        PageObjectLayouter::ModelCoordinateSystem));
+
+    // Determine the color of the page number.
+    Color aPageNumberColor (mpTheme->GetColor(Theme::Color_PageNumberDefault));
+    if (rpDescriptor->HasState(model::PageDescriptor::ST_MouseOver) ||
+        rpDescriptor->HasState(model::PageDescriptor::ST_Selected))
+    {
+        // Page number is painted on background for hover or selection or
+        // both.  Each of these background colors has a predefined luminance
+        // which is compatible with the PageNumberHover color.
+        aPageNumberColor = mpTheme->GetColor(Theme::Color_PageNumberHover);
+    }
+    else
+    {
+        const Color aBackgroundColor (mpTheme->GetColor(Theme::Color_Background));
+        const sal_Int32 nBackgroundLuminance (aBackgroundColor.GetLuminance());
+        // When the background color is black then this is interpreted as
+        // high contrast mode and the font color is set to white.
+        if (nBackgroundLuminance == 0)
+            aPageNumberColor = mpTheme->GetColor(Theme::Color_PageNumberHighContrast);
+        else
+        {
+            // Compare luminance of default page number color and background
+            // color.  When the two are similar then use a darker
+            // (preferred) or brighter font color.
+            const sal_Int32 nFontLuminance (aPageNumberColor.GetLuminance());
+            if (abs(nBackgroundLuminance - nFontLuminance) < 60)
+            {
+                if (nBackgroundLuminance > nFontLuminance-30)
+                    aPageNumberColor = mpTheme->GetColor(Theme::Color_PageNumberBrightBackground);
+                else
+                    aPageNumberColor = mpTheme->GetColor(Theme::Color_PageNumberDarkBackground);
+            }
+        }
+    }
+
+    // Paint the page number.
+    OSL_ASSERT(rpDescriptor->GetPage()!=nullptr);
+    const sal_Int32 nPageNumber ((rpDescriptor->GetPage()->GetPageNum() - 1) / 2 + 1);
+    const OUString sPageNumber(OUString::number(nPageNumber));
+    rDevice.SetFont(*mpPageNumberFont);
+    rDevice.SetTextColor(aPageNumberColor);
+    rDevice.DrawText(aBox, sPageNumber, DrawTextFlags::Right | DrawTextFlags::VCenter);
+}
+
+void PageObjectPainter::PaintTransitionEffect (
+    PageObjectLayouter *pPageObjectLayouter,
+    OutputDevice& rDevice,
+    const model::SharedPageDescriptor& rpDescriptor)
+{
+    const SdPage* pPage = rpDescriptor->GetPage();
+    if (pPage!=nullptr && pPage->getTransitionType() > 0)
+    {
+        const ::tools::Rectangle aBox (pPageObjectLayouter->GetBoundingBox(
+            rpDescriptor,
+            PageObjectLayouter::Part::TransitionEffectIndicator,
+            PageObjectLayouter::ModelCoordinateSystem));
+
+        rDevice.DrawBitmapEx(
+            aBox.TopCenter(),
+            pPageObjectLayouter->GetTransitionEffectIcon().GetBitmapEx());
+    }
+}
+
+void PageObjectPainter::PaintCustomAnimationEffect (
+    PageObjectLayouter *pPageObjectLayouter,
+    OutputDevice& rDevice,
+    const model::SharedPageDescriptor& rpDescriptor)
+{
+    SdPage* pPage = rpDescriptor->GetPage();
+    std::shared_ptr< MainSequence > aMainSequence = pPage->getMainSequence();
+    EffectSequence::iterator aIter = aMainSequence->getBegin();
+    EffectSequence::iterator aEnd = aMainSequence->getEnd();
+    if ( aIter != aEnd )
+    {
+        const ::tools::Rectangle aBox (pPageObjectLayouter->GetBoundingBox(
+            rpDescriptor,
+            PageObjectLayouter::Part::CustomAnimationEffectIndicator,
+            PageObjectLayouter::ModelCoordinateSystem));
+        rDevice.DrawBitmapEx(
+            aBox.TopCenter(),
+            pPageObjectLayouter->GetCustomAnimationEffectIcon().GetBitmapEx());
+    }
+}
+
+void PageObjectPainter::PaintBackgroundDetail (
+    PageObjectLayouter *pPageObjectLayouter,
+    OutputDevice& rDevice,
+    const model::SharedPageDescriptor& rpDescriptor) const
+{
+    enum State { None = 0x00, Selected = 0x01, MouseOver = 0x02, Focused = 0x04 };
+    const int eState =
+          (rpDescriptor->HasState(model::PageDescriptor::ST_Selected) ? Selected : None)
+        | (rpDescriptor->HasState(model::PageDescriptor::ST_MouseOver) ? MouseOver : None)
+        | (rpDescriptor->HasState(model::PageDescriptor::ST_Focused) ? Focused : None);
+
+    bool bHasFocusBorder;
+    Theme::GradientColorType eColorType;
+
+    switch (eState)
+    {
+        case MouseOver | Selected | Focused:
+            eColorType = Theme::Gradient_MouseOverSelectedAndFocusedPage;
+            bHasFocusBorder = true;
+            break;
+
+        case MouseOver | Selected:
+            eColorType = Theme::Gradient_MouseOverSelected;
+            bHasFocusBorder = false;
+            break;
+
+        case MouseOver:
+            eColorType = Theme::Gradient_MouseOverPage;
+            bHasFocusBorder = false;
+            break;
+
+        case MouseOver | Focused:
+            eColorType = Theme::Gradient_MouseOverPage;
+            bHasFocusBorder = true;
+            break;
+
+        case Selected | Focused:
+            eColorType = Theme::Gradient_SelectedAndFocusedPage;
+            bHasFocusBorder = true;
+            break;
+
+        case Selected:
+            eColorType = Theme::Gradient_SelectedPage;
+            bHasFocusBorder = false;
+            break;
+
+        case Focused:
+            eColorType = Theme::Gradient_FocusedPage;
+            bHasFocusBorder = true;
+            break;
+
+        case None:
+        default:
+            eColorType = Theme::Gradient_NormalPage;
+            bHasFocusBorder = false;
+            break;
+    }
+
+    const ::tools::Rectangle aFocusSize (pPageObjectLayouter->GetBoundingBox(
+                                        rpDescriptor,
+                                        PageObjectLayouter::Part::FocusIndicator,
+                                        PageObjectLayouter::ModelCoordinateSystem));
+
+    const ::tools::Rectangle aPageObjectBox (pPageObjectLayouter->GetBoundingBox(
+                                        rpDescriptor,
+                                        PageObjectLayouter::Part::PageObject,
+                                        PageObjectLayouter::ModelCoordinateSystem));
+
+    // Fill the background with the background color of the slide sorter.
+    const Color aBackgroundColor (mpTheme->GetColor(Theme::Color_Background));
+    rDevice.SetFillColor(aBackgroundColor);
+    rDevice.SetLineColor(aBackgroundColor);
+    rDevice.DrawRect(aFocusSize);
+
+    // Paint the slide area with a linear gradient that starts some pixels
+    // below the top and ends some pixels above the bottom.
+    const Color aTopColor(mpTheme->GetGradientColor(eColorType, Theme::GradientColorClass::Fill1));
+    const Color aBottomColor(mpTheme->GetGradientColor(eColorType, Theme::GradientColorClass::Fill2));
+    if (aTopColor != aBottomColor)
+    {
+        Gradient gradient(GradientStyle::Linear, aTopColor, aBottomColor);
+        rDevice.DrawGradient(aPageObjectBox, gradient);
+    }
+    else
+    {
+        rDevice.SetFillColor(aTopColor);
+        rDevice.DrawRect(aPageObjectBox);
+    }
+
+    // Paint the simple border and, for some backgrounds, the focus border.
+    if (bHasFocusBorder)
+        mpFocusBorderPainter->PaintFrame(rDevice, aPageObjectBox);
+    else
+        PaintBorder(rDevice, eColorType, aPageObjectBox);
+
+    // Get bounding box of the preview around which a shadow is painted.
+    // Compensate for the border around the preview.
+    const ::tools::Rectangle aBox (pPageObjectLayouter->GetBoundingBox(
+                                rpDescriptor,
+                                PageObjectLayouter::Part::Preview,
+                                PageObjectLayouter::ModelCoordinateSystem));
+    ::tools::Rectangle aFrameBox (aBox.Left()-1,aBox.Top()-1,aBox.Right()+1,aBox.Bottom()+1);
+    mpShadowPainter->PaintFrame(rDevice, aFrameBox);
+}
+
+void PageObjectPainter::PaintBorder (
+    OutputDevice& rDevice,
+    const Theme::GradientColorType eColorType,
+    const ::tools::Rectangle& rBox) const
+{
+    rDevice.SetFillColor();
+    const sal_Int32 nBorderWidth (1);
+    for (int nIndex=0; nIndex<nBorderWidth; ++nIndex)
+    {
+        const int nDelta (nIndex);
+        rDevice.SetLineColor(mpTheme->GetGradientColor(eColorType, Theme::GradientColorClass::Border2));
+        rDevice.DrawLine(
+            Point(rBox.Left()-nDelta, rBox.Top()-nDelta),
+            Point(rBox.Left()-nDelta, rBox.Bottom()+nDelta));
+        rDevice.DrawLine(
+            Point(rBox.Left()-nDelta, rBox.Bottom()+nDelta),
+            Point(rBox.Right()+nDelta, rBox.Bottom()+nDelta));
+        rDevice.DrawLine(
+            Point(rBox.Right()+nDelta, rBox.Bottom()+nDelta),
+            Point(rBox.Right()+nDelta, rBox.Top()-nDelta));
+
+        rDevice.SetLineColor(mpTheme->GetGradientColor(eColorType, Theme::GradientColorClass::Border1));
+        rDevice.DrawLine(
+            Point(rBox.Left()-nDelta, rBox.Top()-nDelta),
+            Point(rBox.Right()+nDelta, rBox.Top()-nDelta));
+    }
+}
+
+} // end of namespace sd::slidesorter::view
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/view/SlsTheme.cxx b/sd/source/ui/slidesorter/view/SlsTheme.cxx
new file mode 100644
index 000000000..5172e6241
--- /dev/null
+++ b/sd/source/ui/slidesorter/view/SlsTheme.cxx
@@ -0,0 +1,239 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <bitmaps.hlst>
+#include <view/SlsTheme.hxx>
+#include <controller/SlsProperties.hxx>
+#include <tools/color.hxx>
+#include <vcl/outdev.hxx>
+#include <vcl/svapp.hxx>
+#include <vcl/settings.hxx>
+
+#include <osl/diagnose.h>
+
+namespace sd::slidesorter::view {
+
+const Color Black(0x000000);
+const Color White(0xffffff);
+
+static Color ChangeLuminance (Color aColor, const int nValue)
+{
+    if (nValue > 0)
+        aColor.IncreaseLuminance(nValue);
+    else
+        aColor.DecreaseLuminance(-nValue);
+    return aColor;
+}
+
+static Color HGBAdapt (
+    const Color aColor,
+    const sal_Int32 nNewSaturation,
+    const sal_Int32 nNewBrightness)
+{
+    sal_uInt16 nHue (0);
+    sal_uInt16 nSaturation (0);
+    sal_uInt16 nBrightness (0);
+    aColor.RGBtoHSB(nHue, nSaturation, nBrightness);
+    return Color::HSBtoRGB(
+        nHue,
+        nNewSaturation>=0 ? nNewSaturation : nSaturation,
+        nNewBrightness>=0 ? nNewBrightness : nBrightness);
+}
+
+Theme::Theme (const std::shared_ptr<controller::Properties>& rpProperties)
+    : maBackgroundColor(rpProperties->GetBackgroundColor())
+{
+    maColor.resize(ColorType_Size_);
+    maColor[Color_Background] = maBackgroundColor;
+    maColor[Color_PageNumberDefault] = Color(0x0808080);
+    maColor[Color_PageNumberHover] = Color(0x4c4c4c);
+    maColor[Color_PageNumberHighContrast] = White;
+    maColor[Color_PageNumberBrightBackground] = Color(0x333333);
+    maColor[Color_PageNumberDarkBackground] = Color(0xcccccc);
+    maColor[Color_PreviewBorder] = Color(0x949599);
+
+    Update(rpProperties);
+}
+
+void Theme::Update (const std::shared_ptr<controller::Properties>& rpProperties)
+{
+    // Set up colors.
+    maBackgroundColor = rpProperties->GetBackgroundColor();
+
+    maColor[Color_Background] = maBackgroundColor;
+
+    maGradients.resize(GradientColorType_Size_);
+
+    maColor[Color_Background] = maBackgroundColor;
+    const Color aSelectionColor (rpProperties->GetSelectionColor());
+    maColor[Color_Selection] = aSelectionColor;
+    if (aSelectionColor.IsBright())
+        maColor[Color_PageCountFontColor] = Black;
+    else
+        maColor[Color_PageCountFontColor] = White;
+
+    // Set up gradients.
+    SetGradient(Gradient_MouseOverPage, aSelectionColor, 0, 60, +80,+100, +50,+25);
+    SetGradient(Gradient_SelectedPage, aSelectionColor, 50, 50, +80,+100, +50,+25);
+    SetGradient(Gradient_FocusedPage, aSelectionColor, -1,-1, 0,0, -50,-75);
+    SetGradient(Gradient_MouseOverSelected, aSelectionColor, 55, 60, +80,+100, +50,+25);
+    SetGradient(Gradient_SelectedAndFocusedPage, aSelectionColor, 50, 50, +80,+100, -50,-75);
+    SetGradient(Gradient_MouseOverSelectedAndFocusedPage, aSelectionColor, 55, 60, +80,+100, -50,-75);
+
+    SetGradient(Gradient_NormalPage, maBackgroundColor, -1,-1, 0,0, 0,0);
+
+    // The focused gradient needs special handling because its fill color is
+    // like that of the NormalPage gradient.
+    GetGradient(Gradient_FocusedPage).maFillColor1 = GetGradient(Gradient_NormalPage).maFillColor1;
+    GetGradient(Gradient_FocusedPage).maFillColor2 = GetGradient(Gradient_NormalPage).maFillColor2;
+
+    // Set up icons.
+    if (maIcons.empty())
+    {
+        maIcons.resize(IconType_Size_);
+
+        InitializeIcon(Icon_RawShadow, IMAGE_SHADOW);
+        InitializeIcon(Icon_RawInsertShadow, IMAGE_INSERT_SHADOW);
+        InitializeIcon(Icon_HideSlideOverlay, IMAGE_HIDE_SLIDE_OVERLAY);
+        InitializeIcon(Icon_FocusBorder, IMAGE_FOCUS_BORDER);
+    }
+}
+
+std::shared_ptr<vcl::Font> Theme::GetFont (
+    const FontType eType,
+    const OutputDevice& rDevice)
+{
+    std::shared_ptr<vcl::Font> pFont;
+
+    switch (eType)
+    {
+        case Font_PageNumber:
+            pFont = std::make_shared<vcl::Font>(Application::GetSettings().GetStyleSettings().GetAppFont());
+            pFont->SetTransparent(true);
+            pFont->SetWeight(WEIGHT_BOLD);
+            break;
+
+        case Font_PageCount:
+            pFont = std::make_shared<vcl::Font>(Application::GetSettings().GetStyleSettings().GetAppFont());
+            pFont->SetTransparent(true);
+            pFont->SetWeight(WEIGHT_NORMAL);
+            {
+                const Size aSize (pFont->GetFontSize());
+                pFont->SetFontSize(Size(aSize.Width()*5/3, aSize.Height()*5/3));
+            }
+            break;
+    }
+
+    if (pFont)
+    {
+        // Transform the point size to pixel size.
+        const MapMode aFontMapMode (MapUnit::MapPoint);
+        const Size aFontSize (rDevice.LogicToPixel(pFont->GetFontSize(), aFontMapMode));
+
+        // Transform the font size to the logical coordinates of the device.
+        pFont->SetFontSize(rDevice.PixelToLogic(aFontSize));
+    }
+
+    return pFont;
+}
+
+Color Theme::GetColor (const ColorType eType)
+{
+    if (sal_uInt32(eType)<maColor.size())
+        return maColor[eType];
+    else
+        return Color(0);
+}
+
+Color Theme::GetGradientColor (
+    const GradientColorType eType,
+    const GradientColorClass eClass)
+{
+    GradientDescriptor& rDescriptor (GetGradient(eType));
+
+    switch (eClass)
+    {
+        case GradientColorClass::Border1: return rDescriptor.maBorderColor1;
+        case GradientColorClass::Border2: return rDescriptor.maBorderColor2;
+        case GradientColorClass::Fill1: return rDescriptor.maFillColor1;
+        case GradientColorClass::Fill2: return rDescriptor.maFillColor2;
+    }
+    return Color(0);
+}
+
+void Theme::SetGradient (
+    const GradientColorType eType,
+    const Color aBaseColor,
+    const sal_Int32 nSaturationOverride,
+    const sal_Int32 nBrightnessOverride,
+    const sal_Int32 nFillStartOffset,
+    const sal_Int32 nFillEndOffset,
+    const sal_Int32 nBorderStartOffset,
+    const sal_Int32 nBorderEndOffset)
+{
+    GradientDescriptor& rGradient (GetGradient(eType));
+
+    const Color aColor (nSaturationOverride>=0 || nBrightnessOverride>=0
+        ? HGBAdapt(aBaseColor, nSaturationOverride, nBrightnessOverride)
+        : aBaseColor);
+
+    rGradient.maFillColor1 = ChangeLuminance(aColor, nFillStartOffset);
+    rGradient.maFillColor2 = ChangeLuminance(aColor, nFillEndOffset);
+    rGradient.maBorderColor1 = ChangeLuminance(aColor, nBorderStartOffset);
+    rGradient.maBorderColor2 = ChangeLuminance(aColor, nBorderEndOffset);
+}
+
+const BitmapEx& Theme::GetIcon (const IconType eType)
+{
+    if (size_t(eType)<maIcons.size())
+        return maIcons[eType];
+    else
+    {
+        OSL_ASSERT(eType>=0 && size_t(eType)<maIcons.size());
+        return maIcons[0];
+    }
+}
+
+Theme::GradientDescriptor& Theme::GetGradient (const GradientColorType eType)
+{
+    if (size_t(eType)<maGradients.size())
+        return maGradients[eType];
+    else
+    {
+        OSL_ASSERT(eType>=0 && size_t(eType)<maGradients.size());
+        return maGradients[0];
+    }
+}
+
+void Theme::InitializeIcon(const IconType eType, const OUString& rResourceId)
+{
+    if (size_t(eType)<maIcons.size())
+    {
+        const BitmapEx aIcon(rResourceId);
+        maIcons[eType] = aIcon;
+    }
+    else
+    {
+        OSL_ASSERT(eType>=0 && size_t(eType)<maIcons.size());
+    }
+}
+
+} // end of namespace ::sd::slidesorter::view
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/view/SlsToolTip.cxx b/sd/source/ui/slidesorter/view/SlsToolTip.cxx
new file mode 100644
index 000000000..c266bbe3d
--- /dev/null
+++ b/sd/source/ui/slidesorter/view/SlsToolTip.cxx
@@ -0,0 +1,160 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <view/SlsPageObjectLayouter.hxx>
+#include <view/SlsToolTip.hxx>
+#include <view/SlideSorterView.hxx>
+#include <view/SlsLayouter.hxx>
+#include <SlideSorter.hxx>
+#include <Window.hxx>
+#include <sdpage.hxx>
+#include <sdresid.hxx>
+#include <strings.hrc>
+
+#include <osl/diagnose.h>
+#include <vcl/settings.hxx>
+#include <vcl/help.hxx>
+
+namespace sd::slidesorter::view {
+
+ToolTip::ToolTip (SlideSorter& rSlideSorter)
+    : mrSlideSorter(rSlideSorter),
+      mnHelpWindowHandle(nullptr),
+      maShowTimer("sd::slidesorter::view::ToolTip maShowTimer"),
+      maHiddenTimer("sd::slidesorter::view::ToolTip maHiddenTimer")
+{
+    maShowTimer.SetTimeout(HelpSettings::GetTipDelay());
+    maShowTimer.SetInvokeHandler(LINK(this, ToolTip, DelayTrigger));
+    maHiddenTimer.SetTimeout(HelpSettings::GetTipDelay());
+}
+
+ToolTip::~ToolTip()
+{
+    maShowTimer.Stop();
+    maHiddenTimer.Stop();
+    Hide();
+}
+
+void ToolTip::SetPage (const model::SharedPageDescriptor& rpDescriptor)
+{
+    if (mpDescriptor == rpDescriptor)
+        return;
+
+    maShowTimer.Stop();
+    bool bWasVisible = Hide();
+
+    if (bWasVisible)
+    {
+        maHiddenTimer.Start();
+    }
+
+    mpDescriptor = rpDescriptor;
+
+    if (mpDescriptor)
+    {
+        SdPage* pPage = mpDescriptor->GetPage();
+        OUString sHelpText;
+        if (pPage != nullptr)
+            sHelpText = pPage->GetName();
+        else
+        {
+            OSL_ASSERT(mpDescriptor->GetPage() != nullptr);
+        }
+        if (sHelpText.isEmpty())
+        {
+            sHelpText = SdResId(STR_PAGE) +
+                OUString::number(mpDescriptor->GetPageIndex()+1);
+        }
+
+        msCurrentHelpText = sHelpText;
+        // show new tooltip immediately, if last one was recently hidden
+        if(maHiddenTimer.IsActive())
+            DoShow();
+        else
+            maShowTimer.Start();
+    }
+    else
+    {
+        msCurrentHelpText.clear();
+    }
+}
+
+void ToolTip::DoShow()
+{
+    if (maShowTimer.IsActive())
+    {
+        // The delay timer is active.  Wait for it to trigger the showing of
+        // the tool tip.
+        return;
+    }
+
+    sd::Window *pWindow (mrSlideSorter.GetContentWindow().get());
+    if (msCurrentHelpText.isEmpty() || !pWindow)
+        return;
+
+    ::tools::Rectangle aBox (
+        mrSlideSorter.GetView().GetLayouter().GetPageObjectLayouter()->GetBoundingBox(
+            mpDescriptor,
+            PageObjectLayouter::Part::Preview,
+            PageObjectLayouter::WindowCoordinateSystem));
+
+    // Do not show the help text when the (lower edge of the ) preview
+    // is not visible.  The tool tip itself may still be outside the
+    // window.
+    if (aBox.Bottom() >= pWindow->GetSizePixel().Height())
+        return;
+
+    vcl::Window* pParent (pWindow);
+    while (pParent!=nullptr && pParent->GetParent()!=nullptr)
+        pParent = pParent->GetParent();
+    const Point aOffset (pWindow->GetWindowExtentsRelative(pParent).TopLeft());
+
+    // We do not know how high the tool tip will be but want its top
+    // edge not its bottom to be at a specific position (a little below
+    // the preview).  Therefore we use a little trick and place the tool
+    // tip at the top of a rectangle that is placed below the preview.
+    aBox.Move(aOffset.X(), aOffset.Y() + aBox.GetHeight() + 3);
+    mnHelpWindowHandle = Help::ShowPopover(
+        pWindow,
+        aBox,
+        msCurrentHelpText,
+        QuickHelpFlags::Center | QuickHelpFlags::Top);
+}
+
+bool ToolTip::Hide()
+{
+    if (mnHelpWindowHandle)
+    {
+        sd::Window *pWindow (mrSlideSorter.GetContentWindow().get());
+        Help::HidePopover(pWindow, mnHelpWindowHandle);
+        mnHelpWindowHandle = nullptr;
+        return true;
+    }
+    else
+        return false;
+}
+
+IMPL_LINK_NOARG(ToolTip, DelayTrigger, Timer *, void)
+{
+    DoShow();
+}
+
+} // end of namespace ::sd::slidesorter::view
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/view/SlsViewCacheContext.cxx b/sd/source/ui/slidesorter/view/SlsViewCacheContext.cxx
new file mode 100644
index 000000000..ce27cec28
--- /dev/null
+++ b/sd/source/ui/slidesorter/view/SlsViewCacheContext.cxx
@@ -0,0 +1,117 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "SlsViewCacheContext.hxx"
+
+#include <SlideSorter.hxx>
+#include <model/SlideSorterModel.hxx>
+#include <model/SlsPageDescriptor.hxx>
+#include <model/SlsPageEnumerationProvider.hxx>
+#include <view/SlideSorterView.hxx>
+#include <sdpage.hxx>
+#include <Window.hxx>
+#include <drawdoc.hxx>
+#include <tools/IdleDetection.hxx>
+#include <svx/svdpage.hxx>
+
+namespace sd::slidesorter::view {
+
+ViewCacheContext::ViewCacheContext (SlideSorter& rSlideSorter)
+    : mrModel(rSlideSorter.GetModel()),
+      mrSlideSorter(rSlideSorter)
+{
+}
+
+ViewCacheContext::~ViewCacheContext()
+{
+}
+
+void ViewCacheContext::NotifyPreviewCreation(cache::CacheKey aKey)
+{
+    const model::SharedPageDescriptor pDescriptor (GetDescriptor(aKey));
+    if (pDescriptor)
+    {
+        // Force a repaint that will trigger their re-creation.
+        mrSlideSorter.GetView().RequestRepaint(pDescriptor);
+    }
+    else
+    {
+        // It is OK when a preview was created for a page that is not
+        // currently displayed because both normal and master pages are
+        // kept in the same cache.
+    }
+}
+
+bool ViewCacheContext::IsIdle()
+{
+    tools::IdleState nIdleState (tools::IdleDetection::GetIdleState(mrSlideSorter.GetContentWindow()));
+    return nIdleState == tools::IdleState::Idle;
+}
+
+bool ViewCacheContext::IsVisible (cache::CacheKey aKey)
+{
+    const model::SharedPageDescriptor pDescriptor (GetDescriptor(aKey));
+    return pDescriptor && pDescriptor->HasState(model::PageDescriptor::ST_Visible);
+}
+
+const SdrPage* ViewCacheContext::GetPage (cache::CacheKey aKey)
+{
+    return aKey;
+}
+
+std::shared_ptr<std::vector<cache::CacheKey> > ViewCacheContext::GetEntryList (bool bVisible)
+{
+    auto pKeys = std::make_shared<std::vector<cache::CacheKey>>();
+
+    model::PageEnumeration aPageEnumeration (
+        bVisible
+            ? model::PageEnumerationProvider::CreateVisiblePagesEnumeration(mrModel)
+            : model::PageEnumerationProvider::CreateAllPagesEnumeration(mrModel));
+
+    while (aPageEnumeration.HasMoreElements())
+    {
+        model::SharedPageDescriptor pDescriptor (aPageEnumeration.GetNextElement());
+        pKeys->push_back(pDescriptor->GetPage());
+    }
+
+    return pKeys;
+}
+
+sal_Int32 ViewCacheContext::GetPriority (cache::CacheKey aKey)
+{
+    return - (aKey->GetPageNum()-1) / 2;
+}
+
+model::SharedPageDescriptor ViewCacheContext::GetDescriptor (cache::CacheKey aKey)
+{
+    sal_uInt16 nPageIndex ((aKey->GetPageNum() - 1) / 2);
+    return mrModel.GetPageDescriptor(nPageIndex);
+}
+
+css::uno::Reference<css::uno::XInterface> ViewCacheContext::GetModel()
+{
+    if (mrModel.GetDocument() == nullptr)
+        return nullptr;
+    else
+        return mrModel.GetDocument()->getUnoModel();
+}
+
+} // end of namespace ::sd::slidesorter::view
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sd/source/ui/slidesorter/view/SlsViewCacheContext.hxx b/sd/source/ui/slidesorter/view/SlsViewCacheContext.hxx
new file mode 100644
index 000000000..501517cb8
--- /dev/null
+++ b/sd/source/ui/slidesorter/view/SlsViewCacheContext.hxx
@@ -0,0 +1,61 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include <cache/SlsCacheContext.hxx>
+#include <model/SlsSharedPageDescriptor.hxx>
+
+namespace sd::slidesorter::model
+{
+class SlideSorterModel;
+}
+namespace sd::slidesorter
+{
+class SlideSorter;
+}
+
+namespace sd::slidesorter::view
+{
+/** The cache context for the SlideSorter as used by Draw and Impress.  See
+    the base class for documentation of the individual methods.
+*/
+class ViewCacheContext : public cache::CacheContext
+{
+public:
+    explicit ViewCacheContext(SlideSorter& rSlideSorter);
+    virtual ~ViewCacheContext() override;
+    virtual void NotifyPreviewCreation(cache::CacheKey aKey) override;
+    virtual bool IsIdle() override;
+    virtual bool IsVisible(cache::CacheKey aKey) override;
+    virtual const SdrPage* GetPage(cache::CacheKey aKey) override;
+    virtual std::shared_ptr<std::vector<cache::CacheKey>> GetEntryList(bool bVisible) override;
+    virtual sal_Int32 GetPriority(cache::CacheKey aKey) override;
+    virtual css::uno::Reference<css::uno::XInterface> GetModel() override;
+
+private:
+    model::SlideSorterModel& mrModel;
+    SlideSorter& mrSlideSorter;
+
+    model::SharedPageDescriptor GetDescriptor(cache::CacheKey aKey);
+};
+
+} // end of namespace ::sd::slidesorter::view
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */