diff options
Diffstat (limited to 'layout/generic/TextOverflow.cpp')
| -rw-r--r-- | layout/generic/TextOverflow.cpp | 935 |
1 files changed, 935 insertions, 0 deletions
diff --git a/layout/generic/TextOverflow.cpp b/layout/generic/TextOverflow.cpp new file mode 100644 index 0000000000..7d10e7fa5b --- /dev/null +++ b/layout/generic/TextOverflow.cpp @@ -0,0 +1,935 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* 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/. */ + +#include "TextOverflow.h" +#include <algorithm> + +// Please maintain alphabetical order below +#include "gfxContext.h" +#include "nsBlockFrame.h" +#include "nsCaret.h" +#include "nsContentUtils.h" +#include "nsCSSAnonBoxes.h" +#include "nsFontMetrics.h" +#include "nsGfxScrollFrame.h" +#include "nsIScrollableFrame.h" +#include "nsLayoutUtils.h" +#include "nsPresContext.h" +#include "nsRect.h" +#include "nsTextFrame.h" +#include "nsIFrameInlines.h" +#include "mozilla/ArrayUtils.h" +#include "mozilla/Likely.h" +#include "mozilla/PresShell.h" +#include "mozilla/dom/Selection.h" +#include "TextDrawTarget.h" + +using mozilla::layout::TextDrawTarget; + +namespace mozilla { +namespace css { + +class LazyReferenceRenderingDrawTargetGetterFromFrame final + : public gfxFontGroup::LazyReferenceDrawTargetGetter { + public: + typedef mozilla::gfx::DrawTarget DrawTarget; + + explicit LazyReferenceRenderingDrawTargetGetterFromFrame(nsIFrame* aFrame) + : mFrame(aFrame) {} + virtual already_AddRefed<DrawTarget> GetRefDrawTarget() override { + UniquePtr<gfxContext> ctx = + mFrame->PresShell()->CreateReferenceRenderingContext(); + RefPtr<DrawTarget> dt = ctx->GetDrawTarget(); + return dt.forget(); + } + + private: + nsIFrame* mFrame; +}; + +static gfxTextRun* GetEllipsisTextRun(nsIFrame* aFrame) { + RefPtr<nsFontMetrics> fm = + nsLayoutUtils::GetInflatedFontMetricsForFrame(aFrame); + LazyReferenceRenderingDrawTargetGetterFromFrame lazyRefDrawTargetGetter( + aFrame); + return fm->GetThebesFontGroup()->GetEllipsisTextRun( + aFrame->PresContext()->AppUnitsPerDevPixel(), + nsLayoutUtils::GetTextRunOrientFlagsForStyle(aFrame->Style()), + lazyRefDrawTargetGetter); +} + +static nsIFrame* GetSelfOrNearestBlock(nsIFrame* aFrame) { + MOZ_ASSERT(aFrame); + return aFrame->IsBlockFrameOrSubclass() + ? aFrame + : nsLayoutUtils::FindNearestBlockAncestor(aFrame); +} + +// Return true if the frame is an atomic inline-level element. +// It's not supposed to be called for block frames since we never +// process block descendants for text-overflow. +static bool IsAtomicElement(nsIFrame* aFrame, LayoutFrameType aFrameType) { + MOZ_ASSERT(!aFrame->IsBlockFrameOrSubclass() || !aFrame->IsBlockOutside(), + "unexpected block frame"); + MOZ_ASSERT(aFrameType != LayoutFrameType::Placeholder, + "unexpected placeholder frame"); + return !aFrame->IsFrameOfType(nsIFrame::eLineParticipant); +} + +static bool IsFullyClipped(nsTextFrame* aFrame, nscoord aLeft, nscoord aRight, + nscoord* aSnappedLeft, nscoord* aSnappedRight) { + *aSnappedLeft = aLeft; + *aSnappedRight = aRight; + if (aLeft <= 0 && aRight <= 0) { + return false; + } + return !aFrame->MeasureCharClippedText(aLeft, aRight, aSnappedLeft, + aSnappedRight); +} + +static bool IsInlineAxisOverflowVisible(nsIFrame* aFrame) { + MOZ_ASSERT(aFrame && aFrame->IsBlockFrameOrSubclass(), + "expected a block frame"); + + nsIFrame* f = aFrame; + while (f && f->Style()->IsAnonBox() && !f->IsScrollFrame()) { + f = f->GetParent(); + } + if (!f) { + return true; + } + auto overflow = aFrame->GetWritingMode().IsVertical() + ? f->StyleDisplay()->mOverflowY + : f->StyleDisplay()->mOverflowX; + return overflow == StyleOverflow::Visible; +} + +static void ClipMarker(const nsRect& aContentArea, const nsRect& aMarkerRect, + DisplayListClipState::AutoSaveRestore& aClipState) { + nscoord rightOverflow = aMarkerRect.XMost() - aContentArea.XMost(); + nsRect markerRect = aMarkerRect; + if (rightOverflow > 0) { + // Marker overflows on the right side (content width < marker width). + markerRect.width -= rightOverflow; + aClipState.ClipContentDescendants(markerRect); + } else { + nscoord leftOverflow = aContentArea.x - aMarkerRect.x; + if (leftOverflow > 0) { + // Marker overflows on the left side + markerRect.width -= leftOverflow; + markerRect.x += leftOverflow; + aClipState.ClipContentDescendants(markerRect); + } + } +} + +static void InflateIStart(WritingMode aWM, LogicalRect* aRect, nscoord aDelta) { + nscoord iend = aRect->IEnd(aWM); + aRect->IStart(aWM) -= aDelta; + aRect->ISize(aWM) = std::max(iend - aRect->IStart(aWM), 0); +} + +static void InflateIEnd(WritingMode aWM, LogicalRect* aRect, nscoord aDelta) { + aRect->ISize(aWM) = std::max(aRect->ISize(aWM) + aDelta, 0); +} + +static bool IsFrameDescendantOfAny( + nsIFrame* aChild, const TextOverflow::FrameHashtable& aSetOfFrames, + nsIFrame* aCommonAncestor) { + for (nsIFrame* f = aChild; f && f != aCommonAncestor; + f = nsLayoutUtils::GetCrossDocParentFrameInProcess(f)) { + if (aSetOfFrames.Contains(f)) { + return true; + } + } + return false; +} + +class nsDisplayTextOverflowMarker final : public nsPaintedDisplayItem { + public: + nsDisplayTextOverflowMarker(nsDisplayListBuilder* aBuilder, nsIFrame* aFrame, + const nsRect& aRect, nscoord aAscent, + const StyleTextOverflowSide& aStyle) + : nsPaintedDisplayItem(aBuilder, aFrame), + mRect(aRect), + mStyle(aStyle), + mAscent(aAscent) { + MOZ_COUNT_CTOR(nsDisplayTextOverflowMarker); + } + + MOZ_COUNTED_DTOR_OVERRIDE(nsDisplayTextOverflowMarker) + + virtual nsRect GetBounds(nsDisplayListBuilder* aBuilder, + bool* aSnap) const override { + *aSnap = false; + nsRect shadowRect = nsLayoutUtils::GetTextShadowRectsUnion(mRect, mFrame); + return mRect.Union(shadowRect); + } + + virtual nsRect GetComponentAlphaBounds( + nsDisplayListBuilder* aBuilder) const override { + if (gfxPlatform::GetPlatform()->RespectsFontStyleSmoothing()) { + // On OS X, web authors can turn off subpixel text rendering using the + // CSS property -moz-osx-font-smoothing. If they do that, we don't need + // to use component alpha layers for the affected text. + if (mFrame->StyleFont()->mFont.smoothing == NS_FONT_SMOOTHING_GRAYSCALE) { + return nsRect(); + } + } + bool snap; + return GetBounds(aBuilder, &snap); + } + + virtual void Paint(nsDisplayListBuilder* aBuilder, gfxContext* aCtx) override; + + void PaintTextToContext(gfxContext* aCtx, nsPoint aOffsetFromRect); + + virtual bool CreateWebRenderCommands( + mozilla::wr::DisplayListBuilder& aBuilder, + mozilla::wr::IpcResourceUpdateQueue& aResources, + const StackingContextHelper& aSc, + layers::RenderRootStateManager* aManager, + nsDisplayListBuilder* aDisplayListBuilder) override; + + NS_DISPLAY_DECL_NAME("TextOverflow", TYPE_TEXT_OVERFLOW) + private: + nsRect mRect; // in reference frame coordinates + const StyleTextOverflowSide mStyle; + nscoord mAscent; // baseline for the marker text in mRect +}; + +static void PaintTextShadowCallback(gfxContext* aCtx, nsPoint aShadowOffset, + const nscolor& aShadowColor, void* aData) { + reinterpret_cast<nsDisplayTextOverflowMarker*>(aData)->PaintTextToContext( + aCtx, aShadowOffset); +} + +void nsDisplayTextOverflowMarker::Paint(nsDisplayListBuilder* aBuilder, + gfxContext* aCtx) { + nscolor foregroundColor = + nsLayoutUtils::GetColor(mFrame, &nsStyleText::mWebkitTextFillColor); + + // Paint the text-shadows for the overflow marker + nsLayoutUtils::PaintTextShadow(mFrame, aCtx, mRect, + GetPaintRect(aBuilder, aCtx), foregroundColor, + PaintTextShadowCallback, (void*)this); + aCtx->SetColor(gfx::sRGBColor::FromABGR(foregroundColor)); + PaintTextToContext(aCtx, nsPoint(0, 0)); +} + +void nsDisplayTextOverflowMarker::PaintTextToContext(gfxContext* aCtx, + nsPoint aOffsetFromRect) { + WritingMode wm = mFrame->GetWritingMode(); + nsPoint pt(mRect.x, mRect.y); + if (wm.IsVertical()) { + if (wm.IsVerticalLR()) { + pt.x = NSToCoordFloor( + nsLayoutUtils::GetSnappedBaselineX(mFrame, aCtx, pt.x, mAscent)); + } else { + pt.x = NSToCoordFloor(nsLayoutUtils::GetSnappedBaselineX( + mFrame, aCtx, pt.x + mRect.width, -mAscent)); + } + } else { + pt.y = NSToCoordFloor( + nsLayoutUtils::GetSnappedBaselineY(mFrame, aCtx, pt.y, mAscent)); + } + pt += aOffsetFromRect; + + if (mStyle.IsEllipsis()) { + gfxTextRun* textRun = GetEllipsisTextRun(mFrame); + if (textRun) { + NS_ASSERTION(!textRun->IsRightToLeft(), + "Ellipsis textruns should always be LTR!"); + gfx::Point gfxPt(pt.x, pt.y); + textRun->Draw(gfxTextRun::Range(textRun), gfxPt, + gfxTextRun::DrawParams(aCtx)); + } + } else { + RefPtr<nsFontMetrics> fm = + nsLayoutUtils::GetInflatedFontMetricsForFrame(mFrame); + NS_ConvertUTF8toUTF16 str16{mStyle.AsString().AsString()}; + nsLayoutUtils::DrawString(mFrame, *fm, aCtx, str16.get(), str16.Length(), + pt); + } +} + +bool nsDisplayTextOverflowMarker::CreateWebRenderCommands( + mozilla::wr::DisplayListBuilder& aBuilder, + mozilla::wr::IpcResourceUpdateQueue& aResources, + const StackingContextHelper& aSc, layers::RenderRootStateManager* aManager, + nsDisplayListBuilder* aDisplayListBuilder) { + bool snap; + nsRect bounds = GetBounds(aDisplayListBuilder, &snap); + if (bounds.IsEmpty()) { + return true; + } + + // Run the rendering algorithm to capture the glyphs and shadows + RefPtr<TextDrawTarget> textDrawer = + new TextDrawTarget(aBuilder, aResources, aSc, aManager, this, bounds); + MOZ_ASSERT(textDrawer->IsValid()); + if (!textDrawer->IsValid()) { + return false; + } + gfxContext captureCtx(textDrawer); + Paint(aDisplayListBuilder, &captureCtx); + textDrawer->TerminateShadows(); + + return textDrawer->Finish(); +} + +TextOverflow::TextOverflow(nsDisplayListBuilder* aBuilder, + nsBlockFrame* aBlockFrame) + : mContentArea(aBlockFrame->GetWritingMode(), + aBlockFrame->GetContentRectRelativeToSelf(), + aBlockFrame->GetSize()), + mBuilder(aBuilder), + mBlock(aBlockFrame), + mScrollableFrame(nsLayoutUtils::GetScrollableFrameFor(aBlockFrame)), + mMarkerList(aBuilder), + mBlockSize(aBlockFrame->GetSize()), + mBlockWM(aBlockFrame->GetWritingMode()), + mCanHaveInlineAxisScrollbar(false), + mInLineClampContext(aBlockFrame->IsInLineClampContext()), + mAdjustForPixelSnapping(false) { + if (mScrollableFrame) { + auto scrollbarStyle = mBlockWM.IsVertical() + ? mScrollableFrame->GetScrollStyles().mVertical + : mScrollableFrame->GetScrollStyles().mHorizontal; + mCanHaveInlineAxisScrollbar = scrollbarStyle != StyleOverflow::Hidden; + if (!mAdjustForPixelSnapping) { + // Scrolling to the end position can leave some text still overflowing due + // to pixel snapping behaviour in our scrolling code. + mAdjustForPixelSnapping = mCanHaveInlineAxisScrollbar; + } + // Use a null containerSize to convert a vector from logical to physical. + const nsSize nullContainerSize; + mContentArea.MoveBy( + mBlockWM, LogicalPoint(mBlockWM, mScrollableFrame->GetScrollPosition(), + nullContainerSize)); + } + StyleDirection direction = aBlockFrame->StyleVisibility()->mDirection; + const nsStyleTextReset* style = aBlockFrame->StyleTextReset(); + + const auto& textOverflow = style->mTextOverflow; + bool shouldToggleDirection = + textOverflow.sides_are_logical && (direction == StyleDirection::Rtl); + const auto& leftSide = + shouldToggleDirection ? textOverflow.second : textOverflow.first; + const auto& rightSide = + shouldToggleDirection ? textOverflow.first : textOverflow.second; + + if (mBlockWM.IsBidiLTR()) { + mIStart.Init(leftSide); + mIEnd.Init(rightSide); + } else { + mIStart.Init(rightSide); + mIEnd.Init(leftSide); + } + // The left/right marker string is setup in ExamineLineFrames when a line + // has overflow on that side. +} + +/* static */ +Maybe<TextOverflow> TextOverflow::WillProcessLines( + nsDisplayListBuilder* aBuilder, nsBlockFrame* aBlockFrame) { + // Ignore text-overflow and -webkit-line-clamp for event and frame visibility + // processing. + if (aBuilder->IsForEventDelivery() || aBuilder->IsForFrameVisibility() || + !CanHaveOverflowMarkers(aBlockFrame)) { + return Nothing(); + } + nsIScrollableFrame* scrollableFrame = + nsLayoutUtils::GetScrollableFrameFor(aBlockFrame); + if (scrollableFrame && scrollableFrame->IsTransformingByAPZ()) { + // If the APZ is actively scrolling this, don't bother with markers. + return Nothing(); + } + return Some(TextOverflow(aBuilder, aBlockFrame)); +} + +void TextOverflow::ExamineFrameSubtree(nsIFrame* aFrame, + const LogicalRect& aContentArea, + const LogicalRect& aInsideMarkersArea, + FrameHashtable* aFramesToHide, + AlignmentEdges* aAlignmentEdges, + bool* aFoundVisibleTextOrAtomic, + InnerClipEdges* aClippedMarkerEdges) { + const LayoutFrameType frameType = aFrame->Type(); + if (frameType == LayoutFrameType::Br || + frameType == LayoutFrameType::Placeholder) { + return; + } + const bool isAtomic = IsAtomicElement(aFrame, frameType); + if (aFrame->StyleVisibility()->IsVisible()) { + LogicalRect childRect = + GetLogicalScrollableOverflowRectRelativeToBlock(aFrame); + bool overflowIStart = + childRect.IStart(mBlockWM) < aContentArea.IStart(mBlockWM); + bool overflowIEnd = childRect.IEnd(mBlockWM) > aContentArea.IEnd(mBlockWM); + if (overflowIStart) { + mIStart.mHasOverflow = true; + } + if (overflowIEnd) { + mIEnd.mHasOverflow = true; + } + if (isAtomic && ((mIStart.mActive && overflowIStart) || + (mIEnd.mActive && overflowIEnd))) { + aFramesToHide->Insert(aFrame); + } else if (isAtomic || frameType == LayoutFrameType::Text) { + AnalyzeMarkerEdges(aFrame, frameType, aInsideMarkersArea, aFramesToHide, + aAlignmentEdges, aFoundVisibleTextOrAtomic, + aClippedMarkerEdges); + } + } + if (isAtomic) { + return; + } + + for (nsIFrame* child : aFrame->PrincipalChildList()) { + ExamineFrameSubtree(child, aContentArea, aInsideMarkersArea, aFramesToHide, + aAlignmentEdges, aFoundVisibleTextOrAtomic, + aClippedMarkerEdges); + } +} + +void TextOverflow::AnalyzeMarkerEdges(nsIFrame* aFrame, + LayoutFrameType aFrameType, + const LogicalRect& aInsideMarkersArea, + FrameHashtable* aFramesToHide, + AlignmentEdges* aAlignmentEdges, + bool* aFoundVisibleTextOrAtomic, + InnerClipEdges* aClippedMarkerEdges) { + MOZ_ASSERT(aFrameType == LayoutFrameType::Text || + IsAtomicElement(aFrame, aFrameType)); + LogicalRect borderRect(mBlockWM, + nsRect(aFrame->GetOffsetTo(mBlock), aFrame->GetSize()), + mBlockSize); + nscoord istartOverlap = std::max( + aInsideMarkersArea.IStart(mBlockWM) - borderRect.IStart(mBlockWM), 0); + nscoord iendOverlap = std::max( + borderRect.IEnd(mBlockWM) - aInsideMarkersArea.IEnd(mBlockWM), 0); + bool insideIStartEdge = + aInsideMarkersArea.IStart(mBlockWM) <= borderRect.IEnd(mBlockWM); + bool insideIEndEdge = + borderRect.IStart(mBlockWM) <= aInsideMarkersArea.IEnd(mBlockWM); + + if (istartOverlap > 0) { + aClippedMarkerEdges->AccumulateIStart(mBlockWM, borderRect); + if (!mIStart.mActive) { + istartOverlap = 0; + } + } + if (iendOverlap > 0) { + aClippedMarkerEdges->AccumulateIEnd(mBlockWM, borderRect); + if (!mIEnd.mActive) { + iendOverlap = 0; + } + } + + if ((istartOverlap > 0 && insideIStartEdge) || + (iendOverlap > 0 && insideIEndEdge)) { + if (aFrameType == LayoutFrameType::Text) { + auto textFrame = static_cast<nsTextFrame*>(aFrame); + if ((aInsideMarkersArea.IStart(mBlockWM) < + aInsideMarkersArea.IEnd(mBlockWM)) && + textFrame->HasNonSuppressedText()) { + // a clipped text frame and there is some room between the markers + nscoord snappedIStart, snappedIEnd; + bool isFullyClipped = + mBlockWM.IsBidiLTR() + ? IsFullyClipped(textFrame, istartOverlap, iendOverlap, + &snappedIStart, &snappedIEnd) + : IsFullyClipped(textFrame, iendOverlap, istartOverlap, + &snappedIEnd, &snappedIStart); + if (!isFullyClipped) { + LogicalRect snappedRect = borderRect; + if (istartOverlap > 0) { + snappedRect.IStart(mBlockWM) += snappedIStart; + snappedRect.ISize(mBlockWM) -= snappedIStart; + } + if (iendOverlap > 0) { + snappedRect.ISize(mBlockWM) -= snappedIEnd; + } + aAlignmentEdges->AccumulateInner(mBlockWM, snappedRect); + *aFoundVisibleTextOrAtomic = true; + } + } + } else { + aFramesToHide->Insert(aFrame); + } + } else if (!insideIStartEdge || !insideIEndEdge) { + // frame is outside + if (!insideIStartEdge) { + aAlignmentEdges->AccumulateOuter(mBlockWM, borderRect); + } + if (IsAtomicElement(aFrame, aFrameType)) { + aFramesToHide->Insert(aFrame); + } + } else { + // frame is inside + aAlignmentEdges->AccumulateInner(mBlockWM, borderRect); + if (aFrameType == LayoutFrameType::Text) { + auto textFrame = static_cast<nsTextFrame*>(aFrame); + if (textFrame->HasNonSuppressedText()) { + *aFoundVisibleTextOrAtomic = true; + } + } else { + *aFoundVisibleTextOrAtomic = true; + } + } +} + +LogicalRect TextOverflow::ExamineLineFrames(nsLineBox* aLine, + FrameHashtable* aFramesToHide, + AlignmentEdges* aAlignmentEdges) { + // No ellipsing for 'clip' style. + bool suppressIStart = mIStart.IsSuppressed(mInLineClampContext); + bool suppressIEnd = mIEnd.IsSuppressed(mInLineClampContext); + if (mCanHaveInlineAxisScrollbar) { + LogicalPoint pos(mBlockWM, mScrollableFrame->GetScrollPosition(), + mBlockSize); + LogicalRect scrollRange(mBlockWM, mScrollableFrame->GetScrollRange(), + mBlockSize); + // No ellipsing when nothing to scroll to on that side (this includes + // overflow:auto that doesn't trigger a horizontal scrollbar). + if (pos.I(mBlockWM) <= scrollRange.IStart(mBlockWM)) { + suppressIStart = true; + } + if (pos.I(mBlockWM) >= scrollRange.IEnd(mBlockWM)) { + // Except that we always want to display a -webkit-line-clamp ellipsis. + if (!mIEnd.mHasBlockEllipsis) { + suppressIEnd = true; + } + } + } + + LogicalRect contentArea = mContentArea; + bool snapStart = true, snapEnd = true; + nscoord startEdge, endEdge; + if (aLine->GetFloatEdges(&startEdge, &endEdge)) { + // Narrow the |contentArea| to account for any floats on this line, and + // don't bother with the snapping quirk on whichever side(s) we narrow. + nscoord delta = endEdge - contentArea.IEnd(mBlockWM); + if (delta < 0) { + nscoord newSize = contentArea.ISize(mBlockWM) + delta; + contentArea.ISize(mBlockWM) = std::max(nscoord(0), newSize); + snapEnd = false; + } + delta = startEdge - contentArea.IStart(mBlockWM); + if (delta > 0) { + contentArea.IStart(mBlockWM) = startEdge; + nscoord newSize = contentArea.ISize(mBlockWM) - delta; + contentArea.ISize(mBlockWM) = std::max(nscoord(0), newSize); + snapStart = false; + } + } + // Save the non-snapped area since that's what we want to use when placing + // the markers (our return value). The snapped area is only for analysis. + LogicalRect nonSnappedContentArea = contentArea; + if (mAdjustForPixelSnapping) { + const nscoord scrollAdjust = mBlock->PresContext()->AppUnitsPerDevPixel(); + if (snapStart) { + InflateIStart(mBlockWM, &contentArea, scrollAdjust); + } + if (snapEnd) { + InflateIEnd(mBlockWM, &contentArea, scrollAdjust); + } + } + + LogicalRect lineRect(mBlockWM, aLine->ScrollableOverflowRect(), mBlockSize); + const bool istartWantsMarker = + !suppressIStart && + lineRect.IStart(mBlockWM) < contentArea.IStart(mBlockWM); + const bool iendWantsTextOverflowMarker = + !suppressIEnd && lineRect.IEnd(mBlockWM) > contentArea.IEnd(mBlockWM); + const bool iendWantsBlockEllipsisMarker = + !suppressIEnd && mIEnd.mHasBlockEllipsis; + const bool iendWantsMarker = + iendWantsTextOverflowMarker || iendWantsBlockEllipsisMarker; + if (!istartWantsMarker && !iendWantsMarker) { + // We don't need any markers on this line. + return nonSnappedContentArea; + } + + int pass = 0; + bool retryEmptyLine = true; + bool guessIStart = istartWantsMarker; + bool guessIEnd = iendWantsMarker; + mIStart.mActive = istartWantsMarker; + mIEnd.mActive = iendWantsMarker; + mIStart.mEdgeAligned = mCanHaveInlineAxisScrollbar && istartWantsMarker; + mIEnd.mEdgeAligned = + mCanHaveInlineAxisScrollbar && iendWantsTextOverflowMarker; + bool clippedIStartMarker = false; + bool clippedIEndMarker = false; + do { + // Setup marker strings as needed. + if (guessIStart) { + mIStart.SetupString(mBlock); + } + if (guessIEnd) { + mIEnd.SetupString(mBlock); + } + + // If there is insufficient space for both markers then keep the one on the + // end side per the block's 'direction'. + nscoord istartMarkerISize = mIStart.mActive ? mIStart.mISize : 0; + nscoord iendMarkerISize = mIEnd.mActive ? mIEnd.mISize : 0; + if (istartMarkerISize && iendMarkerISize && + istartMarkerISize + iendMarkerISize > contentArea.ISize(mBlockWM)) { + istartMarkerISize = 0; + } + + // Calculate the area between the potential markers aligned at the + // block's edge. + LogicalRect insideMarkersArea = nonSnappedContentArea; + if (guessIStart) { + InflateIStart(mBlockWM, &insideMarkersArea, -istartMarkerISize); + } + if (guessIEnd) { + InflateIEnd(mBlockWM, &insideMarkersArea, -iendMarkerISize); + } + + // Analyze the frames on aLine for the overflow situation at the content + // edges and at the edges of the area between the markers. + bool foundVisibleTextOrAtomic = false; + int32_t n = aLine->GetChildCount(); + nsIFrame* child = aLine->mFirstChild; + InnerClipEdges clippedMarkerEdges; + for (; n-- > 0; child = child->GetNextSibling()) { + ExamineFrameSubtree(child, contentArea, insideMarkersArea, aFramesToHide, + aAlignmentEdges, &foundVisibleTextOrAtomic, + &clippedMarkerEdges); + } + if (!foundVisibleTextOrAtomic && retryEmptyLine) { + aAlignmentEdges->mAssignedInner = false; + aAlignmentEdges->mIEndOuter = 0; + aFramesToHide->Clear(); + pass = -1; + if (mIStart.IsNeeded() && mIStart.mActive && !clippedIStartMarker) { + if (clippedMarkerEdges.mAssignedIStart && + clippedMarkerEdges.mIStart > + nonSnappedContentArea.IStart(mBlockWM)) { + mIStart.mISize = clippedMarkerEdges.mIStart - + nonSnappedContentArea.IStart(mBlockWM); + NS_ASSERTION(mIStart.mISize < mIStart.mIntrinsicISize, + "clipping a marker should make it strictly smaller"); + clippedIStartMarker = true; + } else { + mIStart.mActive = guessIStart = false; + } + continue; + } + if (mIEnd.IsNeeded() && mIEnd.mActive && !clippedIEndMarker) { + if (clippedMarkerEdges.mAssignedIEnd && + nonSnappedContentArea.IEnd(mBlockWM) > clippedMarkerEdges.mIEnd) { + mIEnd.mISize = + nonSnappedContentArea.IEnd(mBlockWM) - clippedMarkerEdges.mIEnd; + NS_ASSERTION(mIEnd.mISize < mIEnd.mIntrinsicISize, + "clipping a marker should make it strictly smaller"); + clippedIEndMarker = true; + } else { + mIEnd.mActive = guessIEnd = false; + } + continue; + } + // The line simply has no visible content even without markers, + // so examine the line again without suppressing markers. + retryEmptyLine = false; + mIStart.mISize = mIStart.mIntrinsicISize; + mIStart.mActive = guessIStart = istartWantsMarker; + mIEnd.mISize = mIEnd.mIntrinsicISize; + mIEnd.mActive = guessIEnd = iendWantsMarker; + // If we wanted to place a block ellipsis but didn't, due to not having + // any visible content to align to or the line's content being scrolled + // out of view, then clip the ellipsis so that it looks like it is aligned + // with the out of view content. + if (mIEnd.IsNeeded() && mIEnd.mActive && mIEnd.mHasBlockEllipsis) { + NS_ASSERTION(nonSnappedContentArea.IStart(mBlockWM) > + aAlignmentEdges->mIEndOuter, + "Expected the alignment edge for the out of view content " + "to be before the start of the content area"); + mIEnd.mISize = std::max( + mIEnd.mIntrinsicISize - (nonSnappedContentArea.IStart(mBlockWM) - + aAlignmentEdges->mIEndOuter), + 0); + } + continue; + } + if (guessIStart == (mIStart.mActive && mIStart.IsNeeded()) && + guessIEnd == (mIEnd.mActive && mIEnd.IsNeeded())) { + break; + } else { + guessIStart = mIStart.mActive && mIStart.IsNeeded(); + guessIEnd = mIEnd.mActive && mIEnd.IsNeeded(); + mIStart.Reset(); + mIEnd.Reset(); + aFramesToHide->Clear(); + } + NS_ASSERTION(pass == 0, "2nd pass should never guess wrong"); + } while (++pass != 2); + if (!istartWantsMarker || !mIStart.mActive) { + mIStart.Reset(); + } + if (!iendWantsMarker || !mIEnd.mActive) { + mIEnd.Reset(); + } + return nonSnappedContentArea; +} + +void TextOverflow::ProcessLine(const nsDisplayListSet& aLists, nsLineBox* aLine, + uint32_t aLineNumber) { + if (mIStart.mStyle->IsClip() && mIEnd.mStyle->IsClip() && + !aLine->HasLineClampEllipsis()) { + return; + } + + mIStart.Reset(); + mIStart.mActive = !mIStart.mStyle->IsClip(); + mIEnd.Reset(); + mIEnd.mHasBlockEllipsis = aLine->HasLineClampEllipsis(); + mIEnd.mActive = !mIEnd.IsSuppressed(mInLineClampContext); + + FrameHashtable framesToHide(64); + AlignmentEdges alignmentEdges; + const LogicalRect contentArea = + ExamineLineFrames(aLine, &framesToHide, &alignmentEdges); + bool needIStart = mIStart.IsNeeded(); + bool needIEnd = mIEnd.IsNeeded(); + if (!needIStart && !needIEnd) { + return; + } + NS_ASSERTION(!mIStart.IsSuppressed(mInLineClampContext) || !needIStart, + "left marker when not needed"); + NS_ASSERTION(!mIEnd.IsSuppressed(mInLineClampContext) || !needIEnd, + "right marker when not needed"); + + // If there is insufficient space for both markers then keep the one on the + // end side per the block's 'direction'. + if (needIStart && needIEnd && + mIStart.mISize + mIEnd.mISize > contentArea.ISize(mBlockWM)) { + needIStart = false; + } + LogicalRect insideMarkersArea = contentArea; + if (needIStart) { + InflateIStart(mBlockWM, &insideMarkersArea, -mIStart.mISize); + } + if (needIEnd) { + InflateIEnd(mBlockWM, &insideMarkersArea, -mIEnd.mISize); + } + + if (alignmentEdges.mAssignedInner) { + if (mIStart.mEdgeAligned) { + alignmentEdges.mIStart = insideMarkersArea.IStart(mBlockWM); + } + if (mIEnd.mEdgeAligned) { + alignmentEdges.mIEnd = insideMarkersArea.IEnd(mBlockWM); + } + LogicalRect alignmentRect(mBlockWM, alignmentEdges.mIStart, + insideMarkersArea.BStart(mBlockWM), + alignmentEdges.ISize(), 1); + insideMarkersArea.IntersectRect(insideMarkersArea, alignmentRect); + } else { + // There was no content on the line that was visible at the current scolled + // position. If we wanted to place a block ellipsis but failed due to + // having no visible content to align it to, we still need to ensure it + // is displayed. It goes at the start of the line, even though it's an + // IEnd marker, since that is the side of the line that the content has + // been scrolled past. We set the insideMarkersArea to a zero-sized + // rectangle placed next to the scrolled-out-of-view content. + if (mIEnd.mHasBlockEllipsis) { + insideMarkersArea = LogicalRect(mBlockWM, alignmentEdges.mIEndOuter, + insideMarkersArea.BStart(mBlockWM), 0, 1); + } + } + + // Clip and remove display items as needed at the final marker edges. + nsDisplayList* lists[] = {aLists.Content(), aLists.PositionedDescendants()}; + for (uint32_t i = 0; i < ArrayLength(lists); ++i) { + PruneDisplayListContents(lists[i], framesToHide, insideMarkersArea); + } + CreateMarkers(aLine, needIStart, needIEnd, insideMarkersArea, contentArea, + aLineNumber); +} + +void TextOverflow::PruneDisplayListContents( + nsDisplayList* aList, const FrameHashtable& aFramesToHide, + const LogicalRect& aInsideMarkersArea) { + for (nsDisplayItem* item : aList->TakeItems()) { + nsIFrame* itemFrame = item->Frame(); + if (IsFrameDescendantOfAny(itemFrame, aFramesToHide, mBlock)) { + item->Destroy(mBuilder); + continue; + } + + nsDisplayList* wrapper = item->GetSameCoordinateSystemChildren(); + if (wrapper) { + if (!itemFrame || GetSelfOrNearestBlock(itemFrame) == mBlock) { + PruneDisplayListContents(wrapper, aFramesToHide, aInsideMarkersArea); + } + } + + nsDisplayText* textItem = + itemFrame ? nsDisplayText::CheckCast(item) : nullptr; + if (textItem && GetSelfOrNearestBlock(itemFrame) == mBlock) { + LogicalRect rect = + GetLogicalScrollableOverflowRectRelativeToBlock(itemFrame); + if (mIStart.IsNeeded()) { + nscoord istart = + aInsideMarkersArea.IStart(mBlockWM) - rect.IStart(mBlockWM); + if (istart > 0) { + (mBlockWM.IsBidiLTR() ? textItem->VisIStartEdge() + : textItem->VisIEndEdge()) = istart; + } + } + if (mIEnd.IsNeeded()) { + nscoord iend = rect.IEnd(mBlockWM) - aInsideMarkersArea.IEnd(mBlockWM); + if (iend > 0) { + (mBlockWM.IsBidiLTR() ? textItem->VisIEndEdge() + : textItem->VisIStartEdge()) = iend; + } + } + } + + aList->AppendToTop(item); + } +} + +/* static */ +bool TextOverflow::HasClippedTextOverflow(nsIFrame* aBlockFrame) { + const nsStyleTextReset* style = aBlockFrame->StyleTextReset(); + return style->mTextOverflow.first.IsClip() && + style->mTextOverflow.second.IsClip(); +} + +/* static */ +bool TextOverflow::HasBlockEllipsis(nsIFrame* aBlockFrame) { + nsBlockFrame* f = do_QueryFrame(aBlockFrame); + return f && f->HasAnyStateBits(NS_BLOCK_HAS_LINE_CLAMP_ELLIPSIS); +} + +static bool BlockCanHaveLineClampEllipsis(nsBlockFrame* aBlockFrame, + bool aBeforeReflow) { + if (aBeforeReflow) { + return aBlockFrame->IsInLineClampContext(); + } + return aBlockFrame->HasAnyStateBits(NS_BLOCK_HAS_LINE_CLAMP_ELLIPSIS); +} + +/* static */ +bool TextOverflow::CanHaveOverflowMarkers(nsBlockFrame* aBlockFrame, + BeforeReflow aBeforeReflow) { + if (BlockCanHaveLineClampEllipsis(aBlockFrame, + aBeforeReflow == BeforeReflow::Yes)) { + return true; + } + + // Nothing to do for text-overflow:clip or if 'overflow-x/y:visible'. + if (HasClippedTextOverflow(aBlockFrame) || + IsInlineAxisOverflowVisible(aBlockFrame)) { + return false; + } + + // Skip ComboboxControlFrame because it would clip the drop-down arrow. + // Its anon block inherits 'text-overflow' and does what is expected. + if (aBlockFrame->IsComboboxControlFrame()) { + return false; + } + + // Inhibit the markers if a descendant content owns the caret. + RefPtr<nsCaret> caret = aBlockFrame->PresShell()->GetCaret(); + if (caret && caret->IsVisible()) { + RefPtr<dom::Selection> domSelection = caret->GetSelection(); + if (domSelection) { + nsCOMPtr<nsIContent> content = + nsIContent::FromNodeOrNull(domSelection->GetFocusNode()); + if (content && + content->IsInclusiveDescendantOf(aBlockFrame->GetContent())) { + return false; + } + } + } + return true; +} + +void TextOverflow::CreateMarkers(const nsLineBox* aLine, bool aCreateIStart, + bool aCreateIEnd, + const LogicalRect& aInsideMarkersArea, + const LogicalRect& aContentArea, + uint32_t aLineNumber) { + if (!mBlock->IsVisibleForPainting()) { + return; + } + + if (aCreateIStart) { + DisplayListClipState::AutoSaveRestore clipState(mBuilder); + + LogicalRect markerLogicalRect( + mBlockWM, aInsideMarkersArea.IStart(mBlockWM) - mIStart.mIntrinsicISize, + aLine->BStart(), mIStart.mIntrinsicISize, aLine->BSize()); + nsPoint offset = mBuilder->ToReferenceFrame(mBlock); + nsRect markerRect = + markerLogicalRect.GetPhysicalRect(mBlockWM, mBlockSize) + offset; + ClipMarker(aContentArea.GetPhysicalRect(mBlockWM, mBlockSize) + offset, + markerRect, clipState); + + mMarkerList.AppendNewToTopWithIndex<nsDisplayTextOverflowMarker>( + mBuilder, mBlock, /* aIndex = */ (aLineNumber << 1) + 0, markerRect, + aLine->GetLogicalAscent(), *mIStart.mStyle); + } + + if (aCreateIEnd) { + DisplayListClipState::AutoSaveRestore clipState(mBuilder); + + LogicalRect markerLogicalRect(mBlockWM, aInsideMarkersArea.IEnd(mBlockWM), + aLine->BStart(), mIEnd.mIntrinsicISize, + aLine->BSize()); + nsPoint offset = mBuilder->ToReferenceFrame(mBlock); + nsRect markerRect = + markerLogicalRect.GetPhysicalRect(mBlockWM, mBlockSize) + offset; + ClipMarker(aContentArea.GetPhysicalRect(mBlockWM, mBlockSize) + offset, + markerRect, clipState); + + mMarkerList.AppendNewToTopWithIndex<nsDisplayTextOverflowMarker>( + mBuilder, mBlock, /* aIndex = */ (aLineNumber << 1) + 1, markerRect, + aLine->GetLogicalAscent(), + mIEnd.mHasBlockEllipsis ? StyleTextOverflowSide::Ellipsis() + : *mIEnd.mStyle); + } +} + +void TextOverflow::Marker::SetupString(nsIFrame* aFrame) { + if (mInitialized) { + return; + } + + // A limitation here is that at the IEnd of a line, we only ever render one of + // a text-overflow marker and a -webkit-line-clamp block ellipsis. Since we + // don't track the block ellipsis string and the text-overflow marker string + // separately, if both apply to the element, we will always use "…" as the + // string for text-overflow. + if (HasBlockEllipsis(aFrame) || mStyle->IsEllipsis()) { + gfxTextRun* textRun = GetEllipsisTextRun(aFrame); + if (textRun) { + mISize = textRun->GetAdvanceWidth(); + } else { + mISize = 0; + } + } else { + UniquePtr<gfxContext> rc = + aFrame->PresShell()->CreateReferenceRenderingContext(); + RefPtr<nsFontMetrics> fm = + nsLayoutUtils::GetInflatedFontMetricsForFrame(aFrame); + mISize = nsLayoutUtils::AppUnitWidthOfStringBidi( + NS_ConvertUTF8toUTF16(mStyle->AsString().AsString()), aFrame, *fm, *rc); + } + mIntrinsicISize = mISize; + mInitialized = true; +} + +} // namespace css +} // namespace mozilla |