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/* -*- 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
#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 "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/ScrollContainerFrame.h"
#include "mozilla/dom/Selection.h"
#include "TextDrawTarget.h"
using mozilla::layout::TextDrawTarget;
namespace mozilla::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->IsLineParticipant();
}
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->IsScrollContainerFrame()) {
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;
return nsLayoutUtils::GetTextShadowRectsUnion(mRect, mFrame);
}
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::GetTextColor(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);
auto& paletteCache = mFrame->PresContext()->FontPaletteCache();
textRun->Draw(gfxTextRun::Range(textRun), gfxPt,
gfxTextRun::DrawParams(aCtx, paletteCache));
}
} else {
RefPtr<nsFontMetrics> fm =
nsLayoutUtils::GetInflatedFontMetricsForFrame(mFrame);
nsDependentAtomString str16(mStyle.AsString().AsAtom());
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),
mScrollContainerFrame(
nsLayoutUtils::GetScrollContainerFrameFor(aBlockFrame)),
mMarkerList(aBuilder),
mBlockSize(aBlockFrame->GetSize()),
mBlockWM(aBlockFrame->GetWritingMode()),
mCanHaveInlineAxisScrollbar(false),
mInLineClampContext(aBlockFrame->IsInLineClampContext()),
mAdjustForPixelSnapping(false) {
if (mScrollContainerFrame) {
auto scrollbarStyle =
mBlockWM.IsVertical()
? mScrollContainerFrame->GetScrollStyles().mVertical
: mScrollContainerFrame->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, mScrollContainerFrame->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();
}
ScrollContainerFrame* scrollContainerFrame =
nsLayoutUtils::GetScrollContainerFrameFor(aBlockFrame);
if (scrollContainerFrame && scrollContainerFrame->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, mScrollContainerFrame->GetScrollPosition(),
mBlockSize);
LogicalRect scrollRange(mBlockWM, mScrollContainerFrame->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 < std::size(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->HasLineClampEllipsis();
}
static bool BlockCanHaveLineClampEllipsis(nsBlockFrame* aBlockFrame,
bool aBeforeReflow) {
if (aBeforeReflow) {
return aBlockFrame->IsInLineClampContext();
}
return aBlockFrame->HasLineClampEllipsis();
}
/* 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 the combobox anonymous block because it would clip the drop-down
// arrow. The inner label inherits 'text-overflow' and does the right thing.
if (aBlockFrame->GetParent() &&
aBlockFrame->GetParent()->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(
nsDependentAtomString(mStyle->AsString().AsAtom()), aFrame, *fm, *rc);
}
mIntrinsicISize = mISize;
mInitialized = true;
}
} // namespace mozilla::css