1 files changed, 65 insertions, 0 deletions
diff --git a/slideshow/source/engine/transitions/waterfallwipe.cxx b/slideshow/source/engine/transitions/waterfallwipe.cxx
new file mode 100644
index 000000000..c3ef81ca5
--- /dev/null
+++ b/slideshow/source/engine/transitions/waterfallwipe.cxx
@@ -0,0 +1,65 @@
+/* -*- 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 <basegfx/point/b2dpoint.hxx>
+#include <basegfx/numeric/ftools.hxx>
+#include <basegfx/matrix/b2dhommatrixtools.hxx>
+#include "waterfallwipe.hxx"
+#include "transitiontools.hxx"
+
+
+namespace slideshow::internal {
+
+WaterfallWipe::WaterfallWipe( sal_Int32 nElements, bool flipOnYAxis )
+    : m_flipOnYAxis( flipOnYAxis )
+{
+    const sal_Int32 sqrtElements = static_cast<sal_Int32>(
+        sqrt( static_cast<double>(nElements) ) );
+    const double elementEdge = 1.0 / sqrtElements;
+    m_waterfall.append( ::basegfx::B2DPoint( 0.0, -1.0 ) );
+    for ( sal_Int32 pos = sqrtElements; pos--; )
+    {
+        const sal_Int32 xPos = sqrtElements - pos - 1;
+        const double yPos = ::basegfx::pruneScaleValue( ((pos + 1) * elementEdge) - 1.0 );
+        m_waterfall.append( ::basegfx::B2DPoint(
+                                ::basegfx::pruneScaleValue( xPos * elementEdge ),
+                                yPos ) );
+        m_waterfall.append( ::basegfx::B2DPoint(
+                                ::basegfx::pruneScaleValue( (xPos + 1) * elementEdge ),
+                                yPos ) );
+    }
+    m_waterfall.append( ::basegfx::B2DPoint( 1.0, -1.0 ) );
+    m_waterfall.setClosed(true);
+}
+
+::basegfx::B2DPolyPolygon WaterfallWipe::operator () ( double t )
+{
+    ::basegfx::B2DPolygon poly( m_waterfall );
+    poly.transform(basegfx::utils::createTranslateB2DHomMatrix(0.0, ::basegfx::pruneScaleValue(2.0 * t)));
+    poly.setB2DPoint( 0, ::basegfx::B2DPoint( 0.0, -1.0 ) );
+    poly.setB2DPoint( poly.count()-1, ::basegfx::B2DPoint( 1.0, -1.0 ) );
+
+    return m_flipOnYAxis ? flipOnYAxis( ::basegfx::B2DPolyPolygon(poly) )
+                         : ::basegfx::B2DPolyPolygon(poly);
+}
+
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */