Google Git
Sign in
webkit / WebKit / f6a2db0b6ffa1cbc502926e8c3265b2be2346307 / . / Source / WebCore / rendering / LegacyLineLayout.cpp
blob: 8ce8f1f73c2caf10b27dd079eea30d80b9932244 [file] [log] [blame]
/*
* Copyright (C) 2000 Lars Knoll (knoll@kde.org)
* Copyright (C) 2003-2019 Apple Inc. All right reserved.
* Copyright (C) 2010 Google Inc. All rights reserved.
* Copyright (C) 2013 ChangSeok Oh <shivamidow@gmail.com>
* Copyright (C) 2013 Adobe Systems Inc. All right reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*
*/
#include "config.h"
#include "LegacyLineLayout.h"
#include "AXObjectCache.h"
#include "BidiResolver.h"
#include "BreakingContext.h"
#include "DocumentInlines.h"
#include "FloatingObjects.h"
#include "HTMLParserIdioms.h"
#include "InlineIteratorBox.h"
#include "InlineIteratorTextBox.h"
#include "InlineTextBoxStyle.h"
#include "InlineWalker.h"
#include "LegacyInlineElementBox.h"
#include "LegacyInlineIterator.h"
#include "LegacyInlineTextBox.h"
#include "LineLayoutState.h"
#include "Logging.h"
#include "RenderBlockFlow.h"
#include "RenderFragmentContainer.h"
#include "RenderFragmentedFlow.h"
#include "RenderLayoutState.h"
#include "RenderLineBreak.h"
#include "RenderRubyBase.h"
#include "RenderRubyText.h"
#include "RenderSVGText.h"
#include "RenderView.h"
#include "SVGElementTypeHelpers.h"
#include "SVGRootInlineBox.h"
#include "Settings.h"
#include "VerticalPositionCache.h"
#include <wtf/StdLibExtras.h>
namespace WebCore {
LegacyLineLayout::LegacyLineLayout(RenderBlockFlow& flow)
: m_flow(flow)
{
}
LegacyLineLayout::~LegacyLineLayout()
{
if (m_flow.containsFloats())
m_flow.floatingObjects()->clearLineBoxTreePointers();
lineBoxes().deleteLineBoxTree();
};
static void determineDirectionality(TextDirection& dir, LegacyInlineIterator iter)
{
while (!iter.atEnd()) {
if (iter.atParagraphSeparator())
return;
if (UChar current = iter.current()) {
UCharDirection charDirection = u_charDirection(current);
if (charDirection == U_LEFT_TO_RIGHT) {
dir = TextDirection::LTR;
return;
}
if (charDirection == U_RIGHT_TO_LEFT || charDirection == U_RIGHT_TO_LEFT_ARABIC) {
dir = TextDirection::RTL;
return;
}
}
iter.increment();
}
}
inline std::unique_ptr<BidiRun> createRun(int start, int end, RenderObject& obj, InlineBidiResolver& resolver)
{
return makeUnique<BidiRun>(start, end, obj, resolver.context(), resolver.dir());
}
void LegacyLineLayout::appendRunsForObject(BidiRunList<BidiRun>* runs, int start, int end, RenderObject& obj, InlineBidiResolver& resolver)
{
if (start > end || RenderBlock::shouldSkipCreatingRunsForObject(obj))
return;
LineWhitespaceCollapsingState& lineWhitespaceCollapsingState = resolver.whitespaceCollapsingState();
bool haveNextTransition = (lineWhitespaceCollapsingState.currentTransition() < lineWhitespaceCollapsingState.numTransitions());
LegacyInlineIterator nextTransition;
if (haveNextTransition)
nextTransition = lineWhitespaceCollapsingState.transitions()[lineWhitespaceCollapsingState.currentTransition()];
if (lineWhitespaceCollapsingState.betweenTransitions()) {
if (!haveNextTransition || (&obj != nextTransition.renderer()))
return;
// This is a new start point. Stop ignoring objects and
// adjust our start.
start = nextTransition.offset();
lineWhitespaceCollapsingState.incrementCurrentTransition();
if (start < end) {
appendRunsForObject(runs, start, end, obj, resolver);
return;
}
} else {
if (!haveNextTransition || (&obj != nextTransition.renderer())) {
if (runs)
runs->appendRun(createRun(start, end, obj, resolver));
return;
}
// An end transition has been encountered within our object. We need to append a run with our endpoint.
if (static_cast<int>(nextTransition.offset() + 1) <= end) {
lineWhitespaceCollapsingState.incrementCurrentTransition();
// The end of the line is before the object we're inspecting. Skip everything and return
if (nextTransition.refersToEndOfPreviousNode())
return;
if (static_cast<int>(nextTransition.offset() + 1) > start && runs)
runs->appendRun(createRun(start, nextTransition.offset() + 1, obj, resolver));
appendRunsForObject(runs, nextTransition.offset() + 1, end, obj, resolver);
} else if (runs)
runs->appendRun(createRun(start, end, obj, resolver));
}
}
std::unique_ptr<LegacyRootInlineBox> LegacyLineLayout::createRootInlineBox()
{
if (is<RenderSVGText>(m_flow)) {
auto box = makeUnique<SVGRootInlineBox>(downcast<RenderSVGText>(m_flow));
box->setHasVirtualLogicalHeight();
return box;
}
return makeUnique<LegacyRootInlineBox>(m_flow);
}
LegacyRootInlineBox* LegacyLineLayout::createAndAppendRootInlineBox()
{
auto newRootBox = createRootInlineBox();
LegacyRootInlineBox* rootBox = newRootBox.get();
m_lineBoxes.appendLineBox(WTFMove(newRootBox));
if (UNLIKELY(AXObjectCache::accessibilityEnabled()) && firstRootBox() == rootBox) {
if (AXObjectCache* cache = m_flow.document().existingAXObjectCache())
cache->deferRecomputeIsIgnored(m_flow.element());
}
return rootBox;
}
LegacyInlineBox* LegacyLineLayout::createInlineBoxForRenderer(RenderObject* renderer, bool isOnlyRun)
{
if (renderer == &m_flow)
return createAndAppendRootInlineBox();
if (is<RenderText>(*renderer))
return downcast<RenderText>(*renderer).createInlineTextBox();
if (is<RenderBox>(*renderer)) {
// FIXME: This is terrible. This branch returns an *owned* pointer!
return downcast<RenderBox>(*renderer).createInlineBox().release();
}
if (is<RenderLineBreak>(*renderer)) {
// FIXME: This is terrible. This branch returns an *owned* pointer!
auto inlineBox = downcast<RenderLineBreak>(*renderer).createInlineBox().release();
// We only treat a box as text for a <br> if we are on a line by ourself or in strict mode
// (Note the use of strict mode. In "almost strict" mode, we don't treat the box for <br> as text.)
inlineBox->setBehavesLikeText(isOnlyRun || renderer->document().inNoQuirksMode() || renderer->isLineBreakOpportunity());
return inlineBox;
}
return downcast<RenderInline>(*renderer).createAndAppendInlineFlowBox();
}
static inline void dirtyLineBoxesForRenderer(RenderObject& renderer, bool fullLayout)
{
if (is<RenderText>(renderer)) {
RenderText& renderText = downcast<RenderText>(renderer);
updateCounterIfNeeded(renderText);
renderText.dirtyLineBoxes(fullLayout);
} else if (is<RenderLineBreak>(renderer))
downcast<RenderLineBreak>(renderer).dirtyLineBoxes(fullLayout);
else
downcast<RenderInline>(renderer).dirtyLineBoxes(fullLayout);
}
static bool parentIsConstructedOrHaveNext(LegacyInlineFlowBox* parentBox)
{
do {
if (parentBox->isConstructed() || parentBox->nextOnLine())
return true;
parentBox = parentBox->parent();
} while (parentBox);
return false;
}
LegacyInlineFlowBox* LegacyLineLayout::createLineBoxes(RenderObject* obj, const LineInfo& lineInfo, LegacyInlineBox* childBox)
{
// See if we have an unconstructed line box for this object that is also
// the last item on the line.
unsigned lineDepth = 1;
LegacyInlineFlowBox* parentBox = nullptr;
LegacyInlineFlowBox* result = nullptr;
bool hasDefaultLineBoxContain = style().lineBoxContain() == RenderStyle::initialLineBoxContain();
do {
RELEASE_ASSERT_WITH_SECURITY_IMPLICATION(is<RenderInline>(*obj) || obj == &m_flow);
RenderInline* inlineFlow = obj != &m_flow ? downcast<RenderInline>(obj) : nullptr;
// Get the last box we made for this render object.
parentBox = inlineFlow ? inlineFlow->lastLineBox() : downcast<RenderBlockFlow>(*obj).lastRootBox();
// If this box or its ancestor is constructed then it is from a previous line, and we need
// to make a new box for our line. If this box or its ancestor is unconstructed but it has
// something following it on the line, then we know we have to make a new box
// as well. In this situation our inline has actually been split in two on
// the same line (this can happen with very fancy language mixtures).
bool constructedNewBox = false;
bool canUseExistingParentBox = parentBox && !parentIsConstructedOrHaveNext(parentBox);
if (!canUseExistingParentBox) {
// We need to make a new box for this render object. Once
// made, we need to place it at the end of the current line.
LegacyInlineBox* newBox = createInlineBoxForRenderer(obj);
parentBox = downcast<LegacyInlineFlowBox>(newBox);
parentBox->setIsFirstLine(lineInfo.isFirstLine());
parentBox->setIsHorizontal(m_flow.isHorizontalWritingMode());
if (!hasDefaultLineBoxContain)
parentBox->clearDescendantsHaveSameLineHeightAndBaseline();
constructedNewBox = true;
}
if (constructedNewBox || canUseExistingParentBox) {
if (!result)
result = parentBox;
// If we have hit the block itself, then |box| represents the root
// inline box for the line, and it doesn't have to be appended to any parent
// inline.
if (childBox)
parentBox->addToLine(childBox);
if (!constructedNewBox || obj == &m_flow)
break;
childBox = parentBox;
}
// If we've exceeded our line depth, then jump straight to the root and skip all the remaining
// intermediate inline flows.
obj = (++lineDepth >= cMaxLineDepth) ? &m_flow : obj->parent();
} while (true);
return result;
}
template<typename CharacterType> static inline bool endsWithHTMLSpaces(const CharacterType* characters, unsigned position, unsigned end)
{
for (unsigned i = position; i < end; ++i) {
if (!isHTMLSpace(characters[i]))
return false;
}
return true;
}
static bool reachedEndOfTextRenderer(const BidiRunList<BidiRun>& bidiRuns)
{
BidiRun* run = bidiRuns.logicallyLastRun();
if (!run)
return true;
if (!is<RenderText>(run->renderer()))
return false;
auto& text = downcast<RenderText>(run->renderer()).text();
unsigned position = run->stop();
unsigned length = text.length();
if (text.is8Bit())
return endsWithHTMLSpaces(text.characters8(), position, length);
return endsWithHTMLSpaces(text.characters16(), position, length);
}
LegacyRootInlineBox* LegacyLineLayout::constructLine(BidiRunList<BidiRun>& bidiRuns, const LineInfo& lineInfo)
{
ASSERT(bidiRuns.firstRun());
LegacyInlineFlowBox* parentBox = 0;
int runCount = bidiRuns.runCount() - lineInfo.runsFromLeadingWhitespace();
for (BidiRun* r = bidiRuns.firstRun(); r; r = r->next()) {
// Create a box for our object.
bool isOnlyRun = (runCount == 1);
if (runCount == 2 && !r->renderer().isListMarker())
isOnlyRun = (!style().isLeftToRightDirection() ? bidiRuns.lastRun() : bidiRuns.firstRun())->renderer().isListMarker();
if (lineInfo.isEmpty())
continue;
LegacyInlineBox* box = createInlineBoxForRenderer(&r->renderer(), isOnlyRun);
r->setBox(box);
// If we have no parent box yet, or if the run is not simply a sibling,
// then we need to construct inline boxes as necessary to properly enclose the
// run's inline box. Segments can only be siblings at the root level, as
// they are positioned separately.
if (!parentBox || &parentBox->renderer() != r->renderer().parent()) {
// Create new inline boxes all the way back to the appropriate insertion point.
RenderObject* parentToUse = r->renderer().parent();
parentBox = createLineBoxes(parentToUse, lineInfo, box);
} else {
// Append the inline box to this line.
parentBox->addToLine(box);
}
box->setBidiLevel(r->level());
if (is<LegacyInlineTextBox>(*box)) {
auto& textBox = downcast<LegacyInlineTextBox>(*box);
textBox.setStart(r->m_start);
textBox.setLen(r->m_stop - r->m_start);
if (r->m_hasHyphen)
textBox.setHasHyphen(true);
}
}
// We should have a root inline box. It should be unconstructed and
// be the last continuation of our line list.
ASSERT(lastRootBox() && !lastRootBox()->isConstructed());
// Set bits on our inline flow boxes that indicate which sides should
// paint borders/margins/padding. This knowledge will ultimately be used when
// we determine the horizontal positions and widths of all the inline boxes on
// the line.
bool isLogicallyLastRunWrapped = bidiRuns.logicallyLastRun()->renderer().isText() ? !reachedEndOfTextRenderer(bidiRuns) : !is<RenderInline>(bidiRuns.logicallyLastRun()->renderer());
lastRootBox()->determineSpacingForFlowBoxes(lineInfo.isLastLine(), isLogicallyLastRunWrapped, &bidiRuns.logicallyLastRun()->renderer());
// Now mark the line boxes as being constructed.
lastRootBox()->setConstructed();
// Return the last line.
return lastRootBox();
}
TextAlignMode LegacyLineLayout::textAlignmentForLine(bool endsWithSoftBreak) const
{
if (auto overrideAlignment = m_flow.overrideTextAlignmentForLine(endsWithSoftBreak))
return *overrideAlignment;
TextAlignMode alignment = style().textAlign();
#if ENABLE(CSS3_TEXT)
TextJustify textJustify = style().textJustify();
if (alignment == TextAlignMode::Justify && textJustify == TextJustify::None)
return style().direction() == TextDirection::LTR ? TextAlignMode::Left : TextAlignMode::Right;
#endif
if (endsWithSoftBreak)
return alignment;
#if !ENABLE(CSS3_TEXT)
return (alignment == TextAlignMode::Justify) ? TextAlignMode::Start : alignment;
#else
if (alignment != TextAlignMode::Justify)
return alignment;
TextAlignLast alignmentLast = style().textAlignLast();
switch (alignmentLast) {
case TextAlignLast::Start:
return TextAlignMode::Start;
case TextAlignLast::End:
return TextAlignMode::End;
case TextAlignLast::Left:
return TextAlignMode::Left;
case TextAlignLast::Right:
return TextAlignMode::Right;
case TextAlignLast::Center:
return TextAlignMode::Center;
case TextAlignLast::Justify:
return TextAlignMode::Justify;
case TextAlignLast::Auto:
if (textJustify == TextJustify::Distribute)
return TextAlignMode::Justify;
return TextAlignMode::Start;
}
return alignment;
#endif
}
static void updateLogicalWidthForLeftAlignedBlock(bool isLeftToRightDirection, BidiRun* trailingSpaceRun, float& logicalLeft, float& totalLogicalWidth, float availableLogicalWidth)
{
// The direction of the block should determine what happens with wide lines.
// In particular with RTL blocks, wide lines should still spill out to the left.
if (isLeftToRightDirection) {
if (totalLogicalWidth > availableLogicalWidth && trailingSpaceRun)
trailingSpaceRun->box()->setLogicalWidth(std::max<float>(0, trailingSpaceRun->box()->logicalWidth() - totalLogicalWidth + availableLogicalWidth));
return;
}
if (trailingSpaceRun)
trailingSpaceRun->box()->setLogicalWidth(0);
else if (totalLogicalWidth > availableLogicalWidth)
logicalLeft -= (totalLogicalWidth - availableLogicalWidth);
}
static void updateLogicalWidthForRightAlignedBlock(bool isLeftToRightDirection, BidiRun* trailingSpaceRun, float& logicalLeft, float& totalLogicalWidth, float availableLogicalWidth)
{
// Wide lines spill out of the block based off direction.
// So even if text-align is right, if direction is LTR, wide lines should overflow out of the right
// side of the block.
if (isLeftToRightDirection) {
if (trailingSpaceRun) {
totalLogicalWidth -= trailingSpaceRun->box()->logicalWidth();
trailingSpaceRun->box()->setLogicalWidth(0);
}
logicalLeft += std::max(0.f, availableLogicalWidth - totalLogicalWidth);
return;
}
if (totalLogicalWidth > availableLogicalWidth && trailingSpaceRun) {
trailingSpaceRun->box()->setLogicalWidth(std::max<float>(0, trailingSpaceRun->box()->logicalWidth() - totalLogicalWidth + availableLogicalWidth));
totalLogicalWidth -= trailingSpaceRun->box()->logicalWidth();
} else
logicalLeft += availableLogicalWidth - totalLogicalWidth;
}
static void updateLogicalWidthForCenterAlignedBlock(bool isLeftToRightDirection, BidiRun* trailingSpaceRun, float& logicalLeft, float& totalLogicalWidth, float availableLogicalWidth)
{
float trailingSpaceWidth = 0;
if (trailingSpaceRun) {
totalLogicalWidth -= trailingSpaceRun->box()->logicalWidth();
trailingSpaceWidth = std::min(trailingSpaceRun->box()->logicalWidth(), (availableLogicalWidth - totalLogicalWidth + 1) / 2);
trailingSpaceRun->box()->setLogicalWidth(std::max<float>(0, trailingSpaceWidth));
}
if (isLeftToRightDirection)
logicalLeft += std::max<float>((availableLogicalWidth - totalLogicalWidth) / 2, 0);
else
logicalLeft += totalLogicalWidth > availableLogicalWidth ? (availableLogicalWidth - totalLogicalWidth) : (availableLogicalWidth - totalLogicalWidth) / 2 - trailingSpaceWidth;
}
void LegacyLineLayout::setMarginsForRubyRun(BidiRun* run, RenderRubyRun& renderer, RenderObject* previousObject, const LineInfo& lineInfo)
{
float startOverhang;
float endOverhang;
RenderObject* nextObject = 0;
for (BidiRun* runWithNextObject = run->next(); runWithNextObject; runWithNextObject = runWithNextObject->next()) {
if (!runWithNextObject->renderer().isOutOfFlowPositioned() && !runWithNextObject->box()->isLineBreak()) {
nextObject = &runWithNextObject->renderer();
break;
}
}
renderer.getOverhang(lineInfo.isFirstLine(), renderer.style().isLeftToRightDirection() ? previousObject : nextObject, renderer.style().isLeftToRightDirection() ? nextObject : previousObject, startOverhang, endOverhang);
m_flow.setMarginStartForChild(renderer, LayoutUnit(-startOverhang));
m_flow.setMarginEndForChild(renderer, LayoutUnit(-endOverhang));
}
static inline void setLogicalWidthForTextRun(LegacyRootInlineBox* lineBox, BidiRun* run, RenderText& renderer, float xPos, const LineInfo& lineInfo,
GlyphOverflowAndFallbackFontsMap& textBoxDataMap, VerticalPositionCache& verticalPositionCache, WordMeasurements& wordMeasurements)
{
HashSet<const Font*> fallbackFonts;
GlyphOverflow glyphOverflow;
const FontCascade& font = lineStyle(*renderer.parent(), lineInfo).fontCascade();
// Always compute glyph overflow if the block's line-box-contain value is "glyphs".
if (lineBox->fitsToGlyphs()) {
// If we don't stick out of the root line's font box, then don't bother computing our glyph overflow. This optimization
// will keep us from computing glyph bounds in nearly all cases.
bool includeRootLine = lineBox->includesRootLineBoxFontOrLeading();
int baselineShift = lineBox->verticalPositionForBox(run->box(), verticalPositionCache);
int rootDescent = includeRootLine ? font.fontMetrics().descent() : 0;
int rootAscent = includeRootLine ? font.fontMetrics().ascent() : 0;
int boxAscent = font.fontMetrics().ascent() - baselineShift;
int boxDescent = font.fontMetrics().descent() + baselineShift;
if (boxAscent > rootDescent || boxDescent > rootAscent)
glyphOverflow.computeBounds = true;
}
LayoutUnit hyphenWidth;
if (downcast<LegacyInlineTextBox>(*run->box()).hasHyphen())
hyphenWidth = measureHyphenWidth(renderer, font, &fallbackFonts);
float measuredWidth = 0;
bool kerningIsEnabled = font.enableKerning();
bool canUseSimpleFontCodePath = renderer.canUseSimpleFontCodePath();
// Since we don't cache glyph overflows, we need to re-measure the run if
// the style is linebox-contain: glyph.
if (!lineBox->fitsToGlyphs() && canUseSimpleFontCodePath) {
unsigned lastEndOffset = run->m_start;
bool atFirstWordMeasurement = true;
for (size_t i = 0, size = wordMeasurements.size(); i < size && lastEndOffset < run->m_stop; ++i) {
WordMeasurement& wordMeasurement = wordMeasurements[i];
if (wordMeasurement.width <= 0 || wordMeasurement.startOffset == wordMeasurement.endOffset)
continue;
if (wordMeasurement.renderer != &renderer || wordMeasurement.startOffset != lastEndOffset || wordMeasurement.endOffset > run->m_stop)
continue;
lastEndOffset = wordMeasurement.endOffset;
if (kerningIsEnabled && lastEndOffset == run->m_stop) {
int wordLength = lastEndOffset - wordMeasurement.startOffset;
GlyphOverflow overflow;
measuredWidth += renderer.width(wordMeasurement.startOffset, wordLength, xPos + measuredWidth, lineInfo.isFirstLine(),
&wordMeasurement.fallbackFonts, &overflow);
UChar c = renderer.characterAt(wordMeasurement.startOffset);
// renderer.width() omits word-spacing value for leading whitespace, so let's just add it back here.
if (!atFirstWordMeasurement && FontCascade::treatAsSpace(c))
measuredWidth += renderer.style().fontCascade().wordSpacing();
} else
measuredWidth += wordMeasurement.width;
atFirstWordMeasurement = false;
for (auto& font : wordMeasurement.fallbackFonts)
fallbackFonts.add(font);
}
if (measuredWidth && lastEndOffset != run->m_stop) {
// If we don't have enough cached data, we'll measure the run again.
measuredWidth = 0;
fallbackFonts.clear();
}
}
if (!measuredWidth)
measuredWidth = renderer.width(run->m_start, run->m_stop - run->m_start, xPos, lineInfo.isFirstLine(), &fallbackFonts, &glyphOverflow);
ASSERT(measuredWidth >= 0);
ASSERT(hyphenWidth >= 0);
run->box()->setLogicalWidth(measuredWidth + hyphenWidth);
if (!fallbackFonts.isEmpty()) {
ASSERT(run->box()->behavesLikeText());
GlyphOverflowAndFallbackFontsMap::iterator it = textBoxDataMap.add(downcast<LegacyInlineTextBox>(run->box()), std::make_pair(Vector<const Font*>(), GlyphOverflow())).iterator;
ASSERT(it->value.first.isEmpty());
it->value.first = copyToVector(fallbackFonts);
run->box()->parent()->clearDescendantsHaveSameLineHeightAndBaseline();
}
// Include text decoration visual overflow as part of the glyph overflow.
if (!renderer.style().textDecorationsInEffect().isEmpty())
glyphOverflow.extendTo(visualOverflowForDecorations(run->box()->lineStyle(), InlineIterator::textBoxFor(downcast<LegacyInlineTextBox>(run->box()))));
if (!glyphOverflow.isEmpty()) {
ASSERT(run->box()->behavesLikeText());
GlyphOverflowAndFallbackFontsMap::iterator it = textBoxDataMap.add(downcast<LegacyInlineTextBox>(run->box()), std::make_pair(Vector<const Font*>(), GlyphOverflow())).iterator;
it->value.second = glyphOverflow;
run->box()->clearKnownToHaveNoOverflow();
}
}
void LegacyLineLayout::updateRubyForJustifiedText(RenderRubyRun& rubyRun, BidiRun& r, const Vector<unsigned, 16>& expansionOpportunities, unsigned& expansionOpportunityCount, float& totalLogicalWidth, float availableLogicalWidth, size_t& i)
{
if (!rubyRun.rubyBase() || !rubyRun.rubyBase()->firstRootBox() || rubyRun.rubyBase()->firstRootBox()->nextRootBox() || !r.renderer().style().collapseWhiteSpace())
return;
auto& rubyBase = *rubyRun.rubyBase();
auto& rootBox = *rubyBase.firstRootBox();
float totalExpansion = 0;
unsigned totalOpportunitiesInRun = 0;
for (auto* leafChild = rootBox.firstLeafDescendant(); leafChild; leafChild = leafChild->nextLeafOnLine()) {
if (!leafChild->isInlineTextBox())
continue;
unsigned opportunitiesInRun = expansionOpportunities[i++];
ASSERT(opportunitiesInRun <= expansionOpportunityCount);
auto expansion = (availableLogicalWidth - totalLogicalWidth) * opportunitiesInRun / expansionOpportunityCount;
totalExpansion += expansion;
totalOpportunitiesInRun += opportunitiesInRun;
}
ASSERT(!rubyRun.hasOverridingLogicalWidth());
float newBaseWidth = rubyRun.logicalWidth() + totalExpansion + m_flow.marginStartForChild(rubyRun) + m_flow.marginEndForChild(rubyRun);
float newRubyRunWidth = rubyRun.logicalWidth() + totalExpansion;
rubyBase.setInitialOffset((newRubyRunWidth - newBaseWidth) / 2);
rubyRun.setOverridingLogicalWidth(LayoutUnit(newRubyRunWidth));
rubyRun.setNeedsLayout(MarkOnlyThis);
rootBox.markDirty();
if (RenderRubyText* rubyText = rubyRun.rubyText()) {
if (LegacyRootInlineBox* textRootBox = rubyText->firstRootBox())
textRootBox->markDirty();
}
rubyRun.layoutBlock(true);
rubyRun.clearOverridingLogicalWidth();
r.box()->setExpansion(newRubyRunWidth - r.box()->logicalWidth());
totalLogicalWidth += totalExpansion;
expansionOpportunityCount -= totalOpportunitiesInRun;
}
void LegacyLineLayout::computeExpansionForJustifiedText(BidiRun* firstRun, BidiRun* trailingSpaceRun, const Vector<unsigned, 16>& expansionOpportunities, unsigned expansionOpportunityCount, float totalLogicalWidth, float availableLogicalWidth)
{
if (!expansionOpportunityCount || availableLogicalWidth <= totalLogicalWidth)
return;
size_t i = 0;
for (BidiRun* run = firstRun; run; run = run->next()) {
if (!run->box() || run == trailingSpaceRun)
continue;
if (is<RenderText>(run->renderer())) {
unsigned opportunitiesInRun = expansionOpportunities[i++];
ASSERT(opportunitiesInRun <= expansionOpportunityCount);
// Only justify text if whitespace is collapsed.
if (run->renderer().style().collapseWhiteSpace()) {
LegacyInlineTextBox& textBox = downcast<LegacyInlineTextBox>(*run->box());
float expansion = (availableLogicalWidth - totalLogicalWidth) * opportunitiesInRun / expansionOpportunityCount;
textBox.setExpansion(expansion);
totalLogicalWidth += expansion;
}
expansionOpportunityCount -= opportunitiesInRun;
} else if (is<RenderRubyRun>(run->renderer()))
updateRubyForJustifiedText(downcast<RenderRubyRun>(run->renderer()), *run, expansionOpportunities, expansionOpportunityCount, totalLogicalWidth, availableLogicalWidth, i);
if (!expansionOpportunityCount)
break;
}
}
void LegacyLineLayout::updateLogicalWidthForAlignment(RenderBlockFlow& flow, const TextAlignMode& textAlign, const LegacyRootInlineBox* rootInlineBox, BidiRun* trailingSpaceRun, float& logicalLeft, float& totalLogicalWidth, float& availableLogicalWidth, int expansionOpportunityCount)
{
TextDirection direction;
if (rootInlineBox && flow.style().unicodeBidi() == Plaintext)
direction = rootInlineBox->direction();
else
direction = flow.style().direction();
bool isLeftToRightDirection = flow.style().isLeftToRightDirection();
// Armed with the total width of the line (without justification),
// we now examine our text-align property in order to determine where to position the
// objects horizontally. The total width of the line can be increased if we end up
// justifying text.
switch (textAlign) {
case TextAlignMode::Left:
case TextAlignMode::WebKitLeft:
updateLogicalWidthForLeftAlignedBlock(isLeftToRightDirection, trailingSpaceRun, logicalLeft, totalLogicalWidth, availableLogicalWidth);
break;
case TextAlignMode::Right:
case TextAlignMode::WebKitRight:
updateLogicalWidthForRightAlignedBlock(isLeftToRightDirection, trailingSpaceRun, logicalLeft, totalLogicalWidth, availableLogicalWidth);
break;
case TextAlignMode::Center:
case TextAlignMode::WebKitCenter:
updateLogicalWidthForCenterAlignedBlock(isLeftToRightDirection, trailingSpaceRun, logicalLeft, totalLogicalWidth, availableLogicalWidth);
break;
case TextAlignMode::Justify:
flow.adjustInlineDirectionLineBounds(expansionOpportunityCount, logicalLeft, availableLogicalWidth);
if (expansionOpportunityCount) {
if (trailingSpaceRun) {
totalLogicalWidth -= trailingSpaceRun->box()->logicalWidth();
trailingSpaceRun->box()->setLogicalWidth(0);
}
break;
}
FALLTHROUGH;
case TextAlignMode::Start:
if (direction == TextDirection::LTR)
updateLogicalWidthForLeftAlignedBlock(isLeftToRightDirection, trailingSpaceRun, logicalLeft, totalLogicalWidth, availableLogicalWidth);
else
updateLogicalWidthForRightAlignedBlock(isLeftToRightDirection, trailingSpaceRun, logicalLeft, totalLogicalWidth, availableLogicalWidth);
break;
case TextAlignMode::End:
if (direction == TextDirection::LTR)
updateLogicalWidthForRightAlignedBlock(isLeftToRightDirection, trailingSpaceRun, logicalLeft, totalLogicalWidth, availableLogicalWidth);
else
updateLogicalWidthForLeftAlignedBlock(isLeftToRightDirection, trailingSpaceRun, logicalLeft, totalLogicalWidth, availableLogicalWidth);
break;
}
}
static void updateLogicalInlinePositions(RenderBlockFlow& block, float& lineLogicalLeft, float& lineLogicalRight, float& availableLogicalWidth, bool firstLine,
IndentTextOrNot shouldIndentText, LayoutUnit boxLogicalHeight)
{
LayoutUnit lineLogicalHeight = block.minLineHeightForReplacedRenderer(firstLine, boxLogicalHeight);
lineLogicalLeft = block.logicalLeftOffsetForLine(block.logicalHeight(), shouldIndentText, lineLogicalHeight);
lineLogicalRight = block.logicalRightOffsetForLine(block.logicalHeight(), shouldIndentText, lineLogicalHeight);
availableLogicalWidth = lineLogicalRight - lineLogicalLeft;
}
void LegacyLineLayout::computeInlineDirectionPositionsForLine(LegacyRootInlineBox* lineBox, const LineInfo& lineInfo, BidiRun* firstRun, BidiRun* trailingSpaceRun, bool reachedEnd, GlyphOverflowAndFallbackFontsMap& textBoxDataMap, VerticalPositionCache& verticalPositionCache, WordMeasurements& wordMeasurements)
{
TextAlignMode textAlign = textAlignmentForLine(!reachedEnd && !lineBox->endsWithBreak());
// CSS 2.1: "'Text-indent' only affects a line if it is the first formatted line of an element. For example, the first line of an anonymous block
// box is only affected if it is the first child of its parent element."
// CSS3 "text-indent", "-webkit-each-line" affects the first line of the block container as well as each line after a forced line break,
// but does not affect lines after a soft wrap break.
bool isFirstLine = lineInfo.isFirstLine() && !(m_flow.isAnonymousBlock() && m_flow.parent()->firstChild() != &m_flow);
bool isAfterHardLineBreak = lineBox->prevRootBox() && lineBox->prevRootBox()->endsWithBreak();
IndentTextOrNot shouldIndentText = requiresIndent(isFirstLine, isAfterHardLineBreak, style());
float lineLogicalLeft;
float lineLogicalRight;
float availableLogicalWidth;
updateLogicalInlinePositions(m_flow, lineLogicalLeft, lineLogicalRight, availableLogicalWidth, isFirstLine, shouldIndentText, 0);
bool needsWordSpacing;
if (firstRun && firstRun->renderer().isReplaced()) {
RenderBox& renderBox = downcast<RenderBox>(firstRun->renderer());
updateLogicalInlinePositions(m_flow, lineLogicalLeft, lineLogicalRight, availableLogicalWidth, isFirstLine, shouldIndentText, renderBox.logicalHeight());
}
computeInlineDirectionPositionsForSegment(lineBox, lineInfo, textAlign, lineLogicalLeft, availableLogicalWidth, firstRun, trailingSpaceRun, textBoxDataMap, verticalPositionCache, wordMeasurements);
// The widths of all runs are now known. We can now place every inline box (and
// compute accurate widths for the inline flow boxes).
needsWordSpacing = false;
lineBox->placeBoxesInInlineDirection(lineLogicalLeft, needsWordSpacing);
}
static inline ExpansionBehavior expansionBehaviorForInlineTextBox(RenderBlockFlow& block, LegacyInlineTextBox& textBox, BidiRun* previousRun, BidiRun* nextRun, TextAlignMode textAlign, bool isAfterExpansion)
{
// Tatechuyoko is modeled as the Object Replacement Character (U+FFFC), which can never have expansion opportunities inside nor intrinsically adjacent to it.
if (textBox.renderer().style().textCombine() == TextCombine::Horizontal)
return ForbidLeftExpansion | ForbidRightExpansion;
ExpansionBehavior result = 0;
bool setLeftExpansion = false;
bool setRightExpansion = false;
if (textAlign == TextAlignMode::Justify) {
// If the next box is ruby, and we're justifying, and the first box in the ruby base has a leading expansion, and we are a text box, then force a trailing expansion.
if (nextRun && is<RenderRubyRun>(nextRun->renderer()) && downcast<RenderRubyRun>(nextRun->renderer()).rubyBase() && nextRun->renderer().style().collapseWhiteSpace()) {
auto& rubyBase = *downcast<RenderRubyRun>(nextRun->renderer()).rubyBase();
if (rubyBase.firstRootBox() && !rubyBase.firstRootBox()->nextRootBox()) {
if (auto* leafChild = rubyBase.firstRootBox()->firstLeafDescendant()) {
if (is<LegacyInlineTextBox>(*leafChild)) {
// FIXME: This leftExpansionOpportunity doesn't actually work because it doesn't perform the UBA
if (FontCascade::leftExpansionOpportunity(downcast<RenderText>(leafChild->renderer()).stringView(), leafChild->direction())) {
setRightExpansion = true;
result |= ForceRightExpansion;
}
}
}
}
}
// Same thing, except if we're following a ruby
if (previousRun && is<RenderRubyRun>(previousRun->renderer()) && downcast<RenderRubyRun>(previousRun->renderer()).rubyBase() && previousRun->renderer().style().collapseWhiteSpace()) {
auto& rubyBase = *downcast<RenderRubyRun>(previousRun->renderer()).rubyBase();
if (rubyBase.firstRootBox() && !rubyBase.firstRootBox()->nextRootBox()) {
if (auto* leafChild = rubyBase.firstRootBox()->lastLeafDescendant()) {
if (is<LegacyInlineTextBox>(*leafChild)) {
// FIXME: This leftExpansionOpportunity doesn't actually work because it doesn't perform the UBA
if (FontCascade::rightExpansionOpportunity(downcast<RenderText>(leafChild->renderer()).stringView(), leafChild->direction())) {
setLeftExpansion = true;
result |= ForceLeftExpansion;
}
}
}
}
}
// If we're the first box inside a ruby base, forbid a leading expansion, and vice-versa
if (is<RenderRubyBase>(block)) {
RenderRubyBase& rubyBase = downcast<RenderRubyBase>(block);
if (&textBox == rubyBase.firstRootBox()->firstLeafDescendant()) {
setLeftExpansion = true;
result |= ForbidLeftExpansion;
} if (&textBox == rubyBase.firstRootBox()->lastLeafDescendant()) {
setRightExpansion = true;
result |= ForbidRightExpansion;
}
}
}
if (!setLeftExpansion)
result |= isAfterExpansion ? ForbidLeftExpansion : AllowLeftExpansion;
if (!setRightExpansion)
result |= AllowRightExpansion;
return result;
}
static inline void applyExpansionBehavior(LegacyInlineTextBox& textBox, ExpansionBehavior expansionBehavior)
{
switch (expansionBehavior & LeftExpansionMask) {
case ForceLeftExpansion:
textBox.setForceLeftExpansion();
break;
case ForbidLeftExpansion:
textBox.setCanHaveLeftExpansion(false);
break;
case AllowLeftExpansion:
textBox.setCanHaveLeftExpansion(true);
break;
default:
ASSERT_NOT_REACHED();
break;
}
switch (expansionBehavior & RightExpansionMask) {
case ForceRightExpansion:
textBox.setForceRightExpansion();
break;
case ForbidRightExpansion:
textBox.setCanHaveRightExpansion(false);
break;
case AllowRightExpansion:
textBox.setCanHaveRightExpansion(true);
break;
default:
ASSERT_NOT_REACHED();
break;
}
}
static bool inlineAncestorHasStartBorderPaddingOrMargin(const RenderBlockFlow& block, const LegacyInlineBox& box)
{
bool isLTR = block.style().isLeftToRightDirection();
for (auto* currentBox = box.parent(); currentBox; currentBox = currentBox->parent()) {
if ((isLTR && currentBox->marginBorderPaddingLogicalLeft() > 0)
|| (!isLTR && currentBox->marginBorderPaddingLogicalRight() > 0))
return true;
}
return false;
}
static bool inlineAncestorHasEndBorderPaddingOrMargin(const RenderBlockFlow& block, const LegacyInlineBox& box)
{
bool isLTR = block.style().isLeftToRightDirection();
for (auto* currentBox = box.parent(); currentBox; currentBox = currentBox->parent()) {
if ((isLTR && currentBox->marginBorderPaddingLogicalRight() > 0)
|| (!isLTR && currentBox->marginBorderPaddingLogicalLeft() > 0))
return true;
}
return false;
}
static bool isLastInFlowRun(BidiRun& runToCheck)
{
for (auto* run = runToCheck.next(); run; run = run->next()) {
if (!run->box() || run->renderer().isOutOfFlowPositioned() || run->box()->isLineBreak())
continue;
return false;
}
return true;
}
BidiRun* LegacyLineLayout::computeInlineDirectionPositionsForSegment(LegacyRootInlineBox* lineBox, const LineInfo& lineInfo, TextAlignMode textAlign, float& lineLogicalLeft,
float& availableLogicalWidth, BidiRun* firstRun, BidiRun* trailingSpaceRun, GlyphOverflowAndFallbackFontsMap& textBoxDataMap, VerticalPositionCache& verticalPositionCache,
WordMeasurements& wordMeasurements)
{
bool needsWordSpacing = false;
bool canHangPunctuationAtStart = style().hangingPunctuation().contains(HangingPunctuation::First);
bool canHangPunctuationAtEnd = style().hangingPunctuation().contains(HangingPunctuation::Last);
bool isLTR = style().isLeftToRightDirection();
float contentWidth = 0;
unsigned expansionOpportunityCount = 0;
bool isAfterExpansion = is<RenderRubyBase>(m_flow) ? downcast<RenderRubyBase>(m_flow).isAfterExpansion() : true;
Vector<unsigned, 16> expansionOpportunities;
HashMap<LegacyInlineTextBox*, LayoutUnit> logicalSpacingForInlineTextBoxes;
auto collectSpacingLogicalWidths = [&] () {
auto totalSpacingWidth = LayoutUnit { };
// Collect the spacing positions (margin, border padding) for the textboxes by traversing the inline tree of the current line.
Vector<LegacyInlineBox*> queue;
queue.append(lineBox);
// 1. Visit each inline box in a preorder fashion
// 2. Accumulate the spacing when we find an LegacyInlineFlowBox (inline container e.g. span)
// 3. Add the LegacyInlineTextBoxes to the hashmap
while (!queue.isEmpty()) {
while (true) {
auto* inlineBox = queue.last();
if (is<LegacyInlineFlowBox>(inlineBox)) {
auto& inlineFlowBox = downcast<LegacyInlineFlowBox>(*inlineBox);
totalSpacingWidth += inlineFlowBox.marginBorderPaddingLogicalLeft();
if (auto* child = inlineFlowBox.firstChild()) {
queue.append(child);
continue;
}
break;
}
if (is<LegacyInlineTextBox>(inlineBox))
logicalSpacingForInlineTextBoxes.add(downcast<LegacyInlineTextBox>(inlineBox), totalSpacingWidth);
break;
}
while (!queue.isEmpty()) {
auto& inlineBox = *queue.takeLast();
if (is<LegacyInlineFlowBox>(inlineBox))
totalSpacingWidth += downcast<LegacyInlineFlowBox>(inlineBox).marginBorderPaddingLogicalRight();
if (auto* nextSibling = inlineBox.nextOnLine()) {
queue.append(nextSibling);
break;
}
}
}
};
collectSpacingLogicalWidths();
BidiRun* run = firstRun;
BidiRun* previousRun = nullptr;
for (; run; run = run->next()) {
auto computeExpansionOpportunities = [&expansionOpportunities, &expansionOpportunityCount, textAlign, &isAfterExpansion] (RenderBlockFlow& block,
LegacyInlineTextBox& textBox, BidiRun* previousRun, BidiRun* nextRun, StringView stringView, TextDirection direction)
{
if (stringView.isEmpty()) {
// Empty runs should still produce an entry in expansionOpportunities list so that the number of items matches the number of runs.
expansionOpportunities.append(0);
return;
}
ExpansionBehavior expansionBehavior = expansionBehaviorForInlineTextBox(block, textBox, previousRun, nextRun, textAlign, isAfterExpansion);
applyExpansionBehavior(textBox, expansionBehavior);
unsigned opportunitiesInRun;
std::tie(opportunitiesInRun, isAfterExpansion) = FontCascade::expansionOpportunityCount(stringView, direction, expansionBehavior);
expansionOpportunities.append(opportunitiesInRun);
expansionOpportunityCount += opportunitiesInRun;
};
if (!run->box() || run->renderer().isOutOfFlowPositioned() || run->box()->isLineBreak()) {
// Positioned objects are only participating to figure out their correct static x position.
// They have no effect on the width. Similarly, line break boxes have no effect on the width.
continue;
}
if (is<RenderText>(run->renderer())) {
auto& renderText = downcast<RenderText>(run->renderer());
auto& textBox = downcast<LegacyInlineTextBox>(*run->box());
if (canHangPunctuationAtStart && lineInfo.isFirstLine() && (isLTR || isLastInFlowRun(*run))
&& !inlineAncestorHasStartBorderPaddingOrMargin(m_flow, *run->box())) {
float hangStartWidth = renderText.hangablePunctuationStartWidth(run->m_start);
availableLogicalWidth += hangStartWidth;
if (style().isLeftToRightDirection())
lineLogicalLeft -= hangStartWidth;
canHangPunctuationAtStart = false;
}
if (canHangPunctuationAtEnd && lineInfo.isLastLine() && run->m_stop > 0 && (!isLTR || isLastInFlowRun(*run))
&& !inlineAncestorHasEndBorderPaddingOrMargin(m_flow, *run->box())) {
float hangEndWidth = renderText.hangablePunctuationEndWidth(run->m_stop - 1);
availableLogicalWidth += hangEndWidth;
if (!style().isLeftToRightDirection())
lineLogicalLeft -= hangEndWidth;
canHangPunctuationAtEnd = false;
}
if (textAlign == TextAlignMode::Justify && run != trailingSpaceRun)
computeExpansionOpportunities(m_flow, textBox, previousRun, run->next(), renderText.stringView(run->m_start, run->m_stop), run->box()->direction());
if (unsigned length = renderText.text().length()) {
if (!run->m_start && needsWordSpacing && isSpaceOrNewline(renderText.characterAt(run->m_start)))
contentWidth += lineStyle(*renderText.parent(), lineInfo).fontCascade().wordSpacing();
// run->m_start == run->m_stop should only be true iff the run is a replaced run for bidi: isolate.
ASSERT(run->m_stop > 0 || run->m_start == run->m_stop);
needsWordSpacing = run->m_stop == length && !isSpaceOrNewline(renderText.characterAt(run->m_stop - 1));
}
auto currentLogicalLeftPosition = logicalSpacingForInlineTextBoxes.get(&textBox) + contentWidth;
setLogicalWidthForTextRun(lineBox, run, renderText, currentLogicalLeftPosition, lineInfo, textBoxDataMap, verticalPositionCache, wordMeasurements);
} else {
canHangPunctuationAtStart = false;
bool encounteredJustifiedRuby = false;
if (is<RenderRubyRun>(run->renderer()) && textAlign == TextAlignMode::Justify && run != trailingSpaceRun && downcast<RenderRubyRun>(run->renderer()).rubyBase()) {
auto* rubyBase = downcast<RenderRubyRun>(run->renderer()).rubyBase();
if (rubyBase->firstRootBox() && !rubyBase->firstRootBox()->nextRootBox() && run->renderer().style().collapseWhiteSpace()) {
rubyBase->setIsAfterExpansion(isAfterExpansion);
for (auto* leafChild = rubyBase->firstRootBox()->firstLeafDescendant(); leafChild; leafChild = leafChild->nextLeafOnLine()) {
if (!is<LegacyInlineTextBox>(*leafChild))
continue;
encounteredJustifiedRuby = true;
computeExpansionOpportunities(*rubyBase, downcast<LegacyInlineTextBox>(*leafChild), nullptr, nullptr,
downcast<RenderText>(leafChild->renderer()).stringView(), leafChild->direction());
}
}
}
if (!encounteredJustifiedRuby)
isAfterExpansion = false;
if (!is<RenderInline>(run->renderer())) {
auto& renderBox = downcast<RenderBox>(run->renderer());
if (is<RenderRubyRun>(renderBox))
setMarginsForRubyRun(run, downcast<RenderRubyRun>(renderBox), previousRun ? &previousRun->renderer() : nullptr, lineInfo);
run->box()->setLogicalWidth(m_flow.logicalWidthForChild(renderBox));
contentWidth += m_flow.marginStartForChild(renderBox) + m_flow.marginEndForChild(renderBox);
}
}
contentWidth += run->box()->logicalWidth();
previousRun = run;
}
if (isAfterExpansion && !expansionOpportunities.isEmpty()) {
// FIXME: see <webkit.org/b/139393#c11>
int lastValidExpansionOpportunitiesIndex = expansionOpportunities.size() - 1;
while (lastValidExpansionOpportunitiesIndex >= 0 && !expansionOpportunities.at(lastValidExpansionOpportunitiesIndex))
--lastValidExpansionOpportunitiesIndex;
if (lastValidExpansionOpportunitiesIndex >= 0) {
ASSERT(expansionOpportunities.at(lastValidExpansionOpportunitiesIndex));
expansionOpportunities.at(lastValidExpansionOpportunitiesIndex)--;
expansionOpportunityCount--;
}
}
if (is<RenderRubyBase>(m_flow) && !expansionOpportunityCount)
textAlign = TextAlignMode::Center;
auto totalLogicalWidth = contentWidth + lineBox->getFlowSpacingLogicalWidth();
updateLogicalWidthForAlignment(m_flow, textAlign, lineBox, trailingSpaceRun, lineLogicalLeft, totalLogicalWidth, availableLogicalWidth, expansionOpportunityCount);
computeExpansionForJustifiedText(firstRun, trailingSpaceRun, expansionOpportunities, expansionOpportunityCount, totalLogicalWidth, availableLogicalWidth);
return run;
}
void LegacyLineLayout::removeInlineBox(BidiRun& run, const LegacyRootInlineBox& rootLineBox) const
{
auto* inlineBox = run.box();
#if ASSERT_ENABLED
auto* inlineParent = inlineBox->parent();
while (inlineParent && inlineParent != &rootLineBox) {
ASSERT(!inlineParent->isDirty());
inlineParent = inlineParent->parent();
}
ASSERT(!rootLineBox.isDirty());
#endif
auto* parent = inlineBox->parent();
inlineBox->removeFromParent();
auto& renderer = run.renderer();
if (is<RenderText>(renderer))
downcast<RenderText>(renderer).removeTextBox(downcast<LegacyInlineTextBox>(*inlineBox));
delete inlineBox;
run.setBox(nullptr);
// removeFromParent() unnecessarily dirties the ancestor subtree.
auto* ancestor = parent;
while (ancestor) {
ancestor->markDirty(false);
if (ancestor == &rootLineBox)
break;
ancestor = ancestor->parent();
}
}
void LegacyLineLayout::computeBlockDirectionPositionsForLine(LegacyRootInlineBox* lineBox, BidiRun* firstRun, GlyphOverflowAndFallbackFontsMap& textBoxDataMap, VerticalPositionCache& verticalPositionCache)
{
m_flow.setLogicalHeight(lineBox->alignBoxesInBlockDirection(m_flow.logicalHeight(), textBoxDataMap, verticalPositionCache));
// Now make sure we place replaced render objects correctly.
for (auto* run = firstRun; run; run = run->next()) {
ASSERT(run->box());
if (!run->box())
continue; // Skip runs with no line boxes.
// Align positioned boxes with the top of the line box. This is
// a reasonable approximation of an appropriate y position.
auto& renderer = run->renderer();
if (renderer.isOutOfFlowPositioned())
run->box()->setLogicalTop(m_flow.logicalHeight());
// Position is used to properly position both replaced elements and
// to update the static normal flow x/y of positioned elements.
bool inlineBoxIsRedundant = false;
if (is<RenderText>(renderer)) {
auto& inlineTextBox = downcast<LegacyInlineTextBox>(*run->box());
downcast<RenderText>(renderer).positionLineBox(inlineTextBox);
inlineBoxIsRedundant = !inlineTextBox.hasTextContent();
} else if (is<RenderBox>(renderer)) {
downcast<RenderBox>(renderer).positionLineBox(downcast<LegacyInlineElementBox>(*run->box()));
inlineBoxIsRedundant = renderer.isOutOfFlowPositioned();
} else if (is<RenderLineBreak>(renderer))
downcast<RenderLineBreak>(renderer).replaceInlineBoxWrapper(downcast<LegacyInlineElementBox>(*run->box()));
// Check if we need to keep this box on the line at all.
if (inlineBoxIsRedundant)
removeInlineBox(*run, *lineBox);
}
}
static inline bool isCollapsibleSpace(UChar character, const RenderText& renderer)
{
if (character == ' ' || character == '\t' || character == softHyphen)
return true;
if (character == '\n')
return !renderer.style().preserveNewline();
if (character == noBreakSpace)
return renderer.style().nbspMode() == NBSPMode::Space;
return false;
}
template <typename CharacterType>
static inline unsigned findFirstTrailingSpace(const RenderText& lastText, const CharacterType* characters, unsigned start, unsigned stop)
{
unsigned firstSpace = stop;
while (firstSpace > start) {
UChar current = characters[firstSpace - 1];
if (!isCollapsibleSpace(current, lastText))
break;
firstSpace--;
}
return firstSpace;
}
inline BidiRun* LegacyLineLayout::handleTrailingSpaces(BidiRunList<BidiRun>& bidiRuns, BidiContext* currentContext)
{
if (!bidiRuns.runCount()
|| !bidiRuns.logicallyLastRun()->renderer().style().breakOnlyAfterWhiteSpace()
|| !bidiRuns.logicallyLastRun()->renderer().style().autoWrap())
return nullptr;
BidiRun* trailingSpaceRun = bidiRuns.logicallyLastRun();
const RenderObject& lastObject = trailingSpaceRun->renderer();
if (!is<RenderText>(lastObject))
return nullptr;
const RenderText& lastText = downcast<RenderText>(lastObject);
unsigned firstSpace;
if (lastText.text().is8Bit())
firstSpace = findFirstTrailingSpace(lastText, lastText.text().characters8(), trailingSpaceRun->start(), trailingSpaceRun->stop());
else
firstSpace = findFirstTrailingSpace(lastText, lastText.text().characters16(), trailingSpaceRun->start(), trailingSpaceRun->stop());
if (firstSpace == trailingSpaceRun->stop())
return nullptr;
TextDirection direction = style().direction();
bool shouldReorder = trailingSpaceRun != (direction == TextDirection::LTR ? bidiRuns.lastRun() : bidiRuns.firstRun());
if (firstSpace != trailingSpaceRun->start()) {
BidiContext* baseContext = currentContext;
while (BidiContext* parent = baseContext->parent())
baseContext = parent;
std::unique_ptr<BidiRun> newTrailingRun = makeUnique<BidiRun>(firstSpace, trailingSpaceRun->m_stop, trailingSpaceRun->renderer(), baseContext, U_OTHER_NEUTRAL);
trailingSpaceRun->m_stop = firstSpace;
trailingSpaceRun = newTrailingRun.get();
if (direction == TextDirection::LTR)
bidiRuns.appendRun(WTFMove(newTrailingRun));
else
bidiRuns.prependRun(WTFMove(newTrailingRun));
return trailingSpaceRun;
}
if (!shouldReorder)
return trailingSpaceRun;
if (direction == TextDirection::LTR) {
bidiRuns.moveRunToEnd(trailingSpaceRun);
trailingSpaceRun->m_level = 0;
} else {
bidiRuns.moveRunToBeginning(trailingSpaceRun);
trailingSpaceRun->m_level = 1;
}
return trailingSpaceRun;
}
void LegacyLineLayout::appendFloatingObjectToLastLine(FloatingObject& floatingObject)
{
ASSERT_WITH_SECURITY_IMPLICATION(!floatingObject.originatingLine());
ASSERT(lastRootBox());
floatingObject.setOriginatingLine(*lastRootBox());
lastRootBox()->appendFloat(floatingObject.renderer());
}
static inline void notifyResolverToResumeInIsolate(InlineBidiResolver& resolver, RenderObject* root, RenderObject* startObject)
{
if (root != startObject) {
RenderObject* parent = startObject->parent();
notifyResolverToResumeInIsolate(resolver, root, parent);
notifyObserverEnteredObject(&resolver, startObject);
}
}
static inline void setUpResolverToResumeInIsolate(InlineBidiResolver& resolver, InlineBidiResolver& topResolver, BidiRun& isolatedRun, RenderObject* root, RenderObject* startObject)
{
// Set up m_whitespaceCollapsingState
resolver.whitespaceCollapsingState() = topResolver.whitespaceCollapsingState();
resolver.whitespaceCollapsingState().setCurrentTransition(topResolver.whitespaceCollapsingTransitionForIsolatedRun(isolatedRun));
// Set up m_nestedIsolateCount
notifyResolverToResumeInIsolate(resolver, root, startObject);
}
// FIXME: BidiResolver should have this logic.
static inline void constructBidiRunsForSegment(InlineBidiResolver& topResolver, BidiRunList<BidiRun>& bidiRuns, const LegacyInlineIterator& endOfRuns, VisualDirectionOverride override, bool previousLineBrokeCleanly)
{
// FIXME: We should pass a BidiRunList into createBidiRunsForLine instead
// of the resolver owning the runs.
ASSERT(&topResolver.runs() == &bidiRuns);
ASSERT(topResolver.position() != endOfRuns);
RenderObject* currentRoot = topResolver.position().root();
topResolver.createBidiRunsForLine(endOfRuns, override, previousLineBrokeCleanly);
while (!topResolver.isolatedRuns().isEmpty()) {
// It does not matter which order we resolve the runs as long as we resolve them all.
auto isolatedRun = WTFMove(topResolver.isolatedRuns().last());
topResolver.isolatedRuns().removeLast();
currentRoot = &isolatedRun.root;
RenderObject& startObject = isolatedRun.object;
// Only inlines make sense with unicode-bidi: isolate (blocks are already isolated).
// FIXME: Because enterIsolate is not passed a RenderObject, we have to crawl up the
// tree to see which parent inline is the isolate. We could change enterIsolate
// to take a RenderObject and do this logic there, but that would be a layering
// violation for BidiResolver (which knows nothing about RenderObject).
RenderInline* isolatedInline = downcast<RenderInline>(highestContainingIsolateWithinRoot(startObject, currentRoot));
ASSERT(isolatedInline);
InlineBidiResolver isolatedResolver;
EUnicodeBidi unicodeBidi = isolatedInline->style().unicodeBidi();
TextDirection direction;
if (unicodeBidi == Plaintext)
determineDirectionality(direction, LegacyInlineIterator(isolatedInline, &isolatedRun.object, 0));
else {
ASSERT(unicodeBidi == Isolate || unicodeBidi == IsolateOverride);
direction = isolatedInline->style().direction();
}
isolatedResolver.setStatus(BidiStatus(direction, isOverride(unicodeBidi)));
setUpResolverToResumeInIsolate(isolatedResolver, topResolver, isolatedRun.runToReplace, isolatedInline, &startObject);
// The starting position is the beginning of the first run within the isolate that was identified
// during the earlier call to createBidiRunsForLine. This can be but is not necessarily the
// first run within the isolate.
LegacyInlineIterator iter = LegacyInlineIterator(isolatedInline, &startObject, isolatedRun.position);
isolatedResolver.setPositionIgnoringNestedIsolates(iter);
// We stop at the next end of line; we may re-enter this isolate in the next call to constructBidiRuns().
// FIXME: What should end and previousLineBrokeCleanly be?
// rniwa says previousLineBrokeCleanly is just a WinIE hack and could always be false here?
isolatedResolver.createBidiRunsForLine(endOfRuns, NoVisualOverride, previousLineBrokeCleanly);
// Note that we do not delete the runs from the resolver.
// We're not guaranteed to get any BidiRuns in the previous step. If we don't, we allow the placeholder
// itself to be turned into an InlineBox. We can't remove it here without potentially losing track of
// the logically last run.
if (isolatedResolver.runs().runCount())
bidiRuns.replaceRunWithRuns(&isolatedRun.runToReplace, isolatedResolver.runs());
// If we encountered any nested isolate runs, just move them
// to the top resolver's list for later processing.
while (!isolatedResolver.isolatedRuns().isEmpty()) {
auto runWithContext = WTFMove(isolatedResolver.isolatedRuns().last());
isolatedResolver.isolatedRuns().removeLast();
topResolver.setWhitespaceCollapsingTransitionForIsolatedRun(runWithContext.runToReplace, isolatedResolver.whitespaceCollapsingTransitionForIsolatedRun(runWithContext.runToReplace));
topResolver.isolatedRuns().append(WTFMove(runWithContext));
}
}
}
// This function constructs line boxes for all of the text runs in the resolver and computes their position.
LegacyRootInlineBox* LegacyLineLayout::createLineBoxesFromBidiRuns(unsigned bidiLevel, BidiRunList<BidiRun>& bidiRuns, const LegacyInlineIterator& end, LineInfo& lineInfo, VerticalPositionCache& verticalPositionCache, BidiRun* trailingSpaceRun, WordMeasurements& wordMeasurements)
{
if (!bidiRuns.runCount())
return nullptr;
// FIXME: Why is this only done when we had runs?
lineInfo.setLastLine(!end.renderer());
LegacyRootInlineBox* lineBox = constructLine(bidiRuns, lineInfo);
if (!lineBox)
return nullptr;
lineBox->setBidiLevel(bidiLevel);
lineBox->setEndsWithBreak(lineInfo.previousLineBrokeCleanly());
bool isSVGRootInlineBox = is<SVGRootInlineBox>(*lineBox);
GlyphOverflowAndFallbackFontsMap textBoxDataMap;
// Now we position all of our text runs horizontally.
if (!isSVGRootInlineBox)
computeInlineDirectionPositionsForLine(lineBox, lineInfo, bidiRuns.firstRun(), trailingSpaceRun, end.atEnd(), textBoxDataMap, verticalPositionCache, wordMeasurements);
// Now position our text runs vertically.
computeBlockDirectionPositionsForLine(lineBox, bidiRuns.firstRun(), textBoxDataMap, verticalPositionCache);
// SVG text layout code computes vertical & horizontal positions on its own.
// Note that we still need to execute computeVerticalPositionsForLine() as
// it calls LegacyInlineTextBox::positionLineBox(), which tracks whether the box
// contains reversed text or not. If we wouldn't do that editing and thus
// text selection in RTL boxes would not work as expected.
if (isSVGRootInlineBox) {
RELEASE_ASSERT_WITH_SECURITY_IMPLICATION(m_flow.isSVGText());
downcast<SVGRootInlineBox>(*lineBox).computePerCharacterLayoutInformation();
}
// Compute our overflow now.
lineBox->computeOverflow(lineBox->lineTop(), lineBox->lineBottom(), textBoxDataMap);
return lineBox;
}
static void deleteLineRange(LineLayoutState& layoutState, LegacyRootInlineBox* startLine, LegacyRootInlineBox* stopLine = 0)
{
LegacyRootInlineBox* boxToDelete = startLine;
while (boxToDelete && boxToDelete != stopLine) {
layoutState.updateRepaintRangeFromBox(boxToDelete);
// Note: deleteLineRange(firstRootBox()) is not identical to deleteLineBoxTree().
// deleteLineBoxTree uses nextLineBox() instead of nextRootBox() when traversing.
LegacyRootInlineBox* next = boxToDelete->nextRootBox();
boxToDelete->deleteLine();
boxToDelete = next;
}
}
static void repaintDirtyFloats(LineLayoutState::FloatList& floats)
{
// Floats that did not have layout did not repaint when we laid them out. They would have
// painted by now if they had moved, but if they stayed at (0, 0), they still need to be
// painted.
for (auto& floatBox : floats) {
if (floatBox->everHadLayout())
continue;
auto& box = floatBox->renderer();
if (!box.x() && !box.y() && box.checkForRepaintDuringLayout())
box.repaint();
}
}
void LegacyLineLayout::layoutRunsAndFloats(LineLayoutState& layoutState, bool hasInlineChild)
{
// We want to skip ahead to the first dirty line
InlineBidiResolver resolver;
LegacyRootInlineBox* startLine = determineStartPosition(layoutState, resolver);
unsigned consecutiveHyphenatedLines = 0;
if (startLine) {
for (auto* line = startLine->prevRootBox(); line && line->isHyphenated(); line = line->prevRootBox())
consecutiveHyphenatedLines++;
}
// FIXME: This would make more sense outside of this function, but since
// determineStartPosition can change the fullLayout flag we have to do this here. Failure to call
// determineStartPosition first will break fast/repaint/line-flow-with-floats-9.html.
if (layoutState.isFullLayout() && hasInlineChild && !m_flow.selfNeedsLayout()) {
m_flow.setNeedsLayout(MarkOnlyThis); // Mark as needing a full layout to force us to repaint.
if (!layoutContext().needsFullRepaint() && m_flow.layerRepaintRects()) {
// Because we waited until we were already inside layout to discover
// that the block really needed a full layout, we missed our chance to repaint the layer
// before layout started. Luckily the layer has cached the repaint rect for its original
// position and size, and so we can use that to make a repaint happen now.
m_flow.repaintUsingContainer(m_flow.containerForRepaint(), m_flow.layerRepaintRects()->clippedOverflowRect);
}
}
if (m_flow.containsFloats())
layoutState.floatList().setLastFloat(m_flow.floatingObjects()->set().last().get());
// We also find the first clean line and extract these lines. We will add them back
// if we determine that we're able to synchronize after handling all our dirty lines.
LegacyInlineIterator cleanLineStart;
BidiStatus cleanLineBidiStatus;
if (!layoutState.isFullLayout() && startLine)
determineEndPosition(layoutState, startLine, cleanLineStart, cleanLineBidiStatus);
if (startLine) {
if (!layoutState.usesRepaintBounds())
layoutState.setRepaintRange(m_flow.logicalHeight());
deleteLineRange(layoutState, startLine);
}
if (!layoutState.isFullLayout() && lastRootBox() && lastRootBox()->endsWithBreak()) {
// If the last line before the start line ends with a line break that clear floats,
// adjust the height accordingly.
// A line break can be either the first or the last object on a line, depending on its direction.
if (LegacyInlineBox* lastLeafDescendant = lastRootBox()->lastLeafDescendant()) {
RenderObject* lastObject = &lastLeafDescendant->renderer();
if (!lastObject->isBR())
lastObject = &lastRootBox()->firstLeafDescendant()->renderer();
if (lastObject->isBR()) {
auto clear = RenderStyle::usedClear(*lastObject);
if (clear != UsedClear::None)
m_flow.clearFloats(clear);
}
}
}
layoutRunsAndFloatsInRange(layoutState, resolver, cleanLineStart, cleanLineBidiStatus, consecutiveHyphenatedLines);
linkToEndLineIfNeeded(layoutState);
repaintDirtyFloats(layoutState.floatList());
}
// Before restarting the layout loop with a new logicalHeight, remove all floats that were added and reset the resolver.
inline const LegacyInlineIterator& LegacyLineLayout::restartLayoutRunsAndFloatsInRange(LayoutUnit oldLogicalHeight, LayoutUnit newLogicalHeight, FloatingObject* lastFloatFromPreviousLine, InlineBidiResolver& resolver, const LegacyInlineIterator& oldEnd)
{
m_flow.removeFloatingObjectsBelow(lastFloatFromPreviousLine, oldLogicalHeight);
m_flow.setLogicalHeight(newLogicalHeight);
resolver.setPositionIgnoringNestedIsolates(oldEnd);
return oldEnd;
}
void LegacyLineLayout::layoutRunsAndFloatsInRange(LineLayoutState& layoutState, InlineBidiResolver& resolver, const LegacyInlineIterator& cleanLineStart, const BidiStatus& cleanLineBidiStatus, unsigned consecutiveHyphenatedLines)
{
const RenderStyle& styleToUse = style();
bool paginated = layoutContext().layoutState() && layoutContext().layoutState()->isPaginated();
LineWhitespaceCollapsingState& lineWhitespaceCollapsingState = resolver.whitespaceCollapsingState();
LegacyInlineIterator end = resolver.position();
bool checkForEndLineMatch = layoutState.endLine();
RenderTextInfo renderTextInfo;
VerticalPositionCache verticalPositionCache;
LineBreaker lineBreaker(m_flow);
while (!end.atEnd()) {
// FIXME: Is this check necessary before the first iteration or can it be moved to the end?
if (checkForEndLineMatch) {
layoutState.setEndLineMatched(matchedEndLine(layoutState, resolver, cleanLineStart, cleanLineBidiStatus));
if (layoutState.endLineMatched()) {
resolver.setPosition(LegacyInlineIterator(resolver.position().root(), 0, 0), 0);
layoutState.marginInfo().clearMargin();
break;
}
}
lineWhitespaceCollapsingState.reset();
layoutState.lineInfo().setEmpty(true);
layoutState.lineInfo().resetRunsFromLeadingWhitespace();
const LegacyInlineIterator oldEnd = end;
bool isNewUBAParagraph = layoutState.lineInfo().previousLineBrokeCleanly();
FloatingObject* lastFloatFromPreviousLine = (m_flow.containsFloats()) ? m_flow.floatingObjects()->set().last().get() : nullptr;
WordMeasurements wordMeasurements;
end = lineBreaker.nextLineBreak(resolver, layoutState.lineInfo(), renderTextInfo, lastFloatFromPreviousLine, consecutiveHyphenatedLines, wordMeasurements);
m_flow.cachePriorCharactersIfNeeded(renderTextInfo.lineBreakIterator);
renderTextInfo.lineBreakIterator.resetPriorContext();
if (resolver.position().atEnd()) {
// FIXME: We shouldn't be creating any runs in nextLineBreak to begin with!
// Once BidiRunList is separated from BidiResolver this will not be needed.
resolver.runs().clear();
resolver.markCurrentRunEmpty(); // FIXME: This can probably be replaced by an ASSERT (or just removed).
layoutState.setCheckForFloatsFromLastLine(true);
resolver.setPosition(LegacyInlineIterator(resolver.position().root(), 0, 0), 0);
break;
}
ASSERT(end != resolver.position());
// This is a short-cut for empty lines.
if (layoutState.lineInfo().isEmpty()) {
if (lastRootBox())
lastRootBox()->setLineBreakInfo(end.renderer(), end.offset(), resolver.status());
} else {
VisualDirectionOverride override = (styleToUse.rtlOrdering() == Order::Visual ? (styleToUse.direction() == TextDirection::LTR ? VisualLeftToRightOverride : VisualRightToLeftOverride) : NoVisualOverride);
if (isNewUBAParagraph && styleToUse.unicodeBidi() == Plaintext && !resolver.context()->parent()) {
TextDirection direction = styleToUse.direction();
determineDirectionality(direction, resolver.position());
resolver.setStatus(BidiStatus(direction, isOverride(styleToUse.unicodeBidi())));
}
// FIXME: This ownership is reversed. We should own the BidiRunList and pass it to createBidiRunsForLine.
BidiRunList<BidiRun>& bidiRuns = resolver.runs();
constructBidiRunsForSegment(resolver, bidiRuns, end, override, layoutState.lineInfo().previousLineBrokeCleanly());
ASSERT(resolver.position() == end);
BidiRun* trailingSpaceRun = !layoutState.lineInfo().previousLineBrokeCleanly() ? handleTrailingSpaces(bidiRuns, resolver.context()) : nullptr;
if (bidiRuns.runCount() && lineBreaker.lineWasHyphenated()) {
bidiRuns.logicallyLastRun()->m_hasHyphen = true;
consecutiveHyphenatedLines++;
} else
consecutiveHyphenatedLines = 0;
// Now that the runs have been ordered, we create the line boxes.
// At the same time we figure out where border/padding/margin should be applied for
// inline flow boxes.
LayoutUnit oldLogicalHeight = m_flow.logicalHeight();
LegacyRootInlineBox* lineBox = createLineBoxesFromBidiRuns(resolver.status().context->level(), bidiRuns, end, layoutState.lineInfo(), verticalPositionCache, trailingSpaceRun, wordMeasurements);
bidiRuns.clear();
resolver.markCurrentRunEmpty(); // FIXME: This can probably be replaced by an ASSERT (or just removed).
if (lineBox) {
lineBox->setLineBreakInfo(end.renderer(), end.offset(), resolver.status());
if (layoutState.usesRepaintBounds())
layoutState.updateRepaintRangeFromBox(lineBox);
LayoutUnit adjustment;
bool overflowsFragment = false;
layoutState.marginInfo().setAtBeforeSideOfBlock(false);
if (paginated)
m_flow.adjustLinePositionForPagination(lineBox, adjustment, overflowsFragment, layoutState.fragmentedFlow());
if (adjustment) {
IndentTextOrNot shouldIndentText = layoutState.lineInfo().isFirstLine() ? IndentText : DoNotIndentText;
LayoutUnit oldLineWidth = m_flow.availableLogicalWidthForLine(oldLogicalHeight, shouldIndentText);
lineBox->adjustBlockDirectionPosition(adjustment);
if (layoutState.usesRepaintBounds())
layoutState.updateRepaintRangeFromBox(lineBox);
if (m_flow.availableLogicalWidthForLine(oldLogicalHeight + adjustment, shouldIndentText) != oldLineWidth) {
// We have to delete this line, remove all floats that got added, and let line layout re-run.
lineBox->deleteLine();
end = restartLayoutRunsAndFloatsInRange(oldLogicalHeight, oldLogicalHeight + adjustment, lastFloatFromPreviousLine, resolver, oldEnd);
continue;
}
m_flow.setLogicalHeight(lineBox->lineBoxBottom());
}
if (paginated) {
if (layoutState.fragmentedFlow())
updateFragmentForLine(lineBox);
}
}
}
for (size_t i = 0; i < lineBreaker.positionedObjects().size(); ++i)
setStaticPositions(m_flow, *lineBreaker.positionedObjects()[i], DoNotIndentText);
if (!layoutState.lineInfo().isEmpty()) {
layoutState.lineInfo().setFirstLine(false);
m_flow.clearFloats(lineBreaker.usedClear());
}
if (m_flow.floatingObjects() && lastRootBox()) {
const FloatingObjectSet& floatingObjectSet = m_flow.floatingObjects()->set();
auto it = floatingObjectSet.begin();
auto end = floatingObjectSet.end();
if (auto* lastFloat = layoutState.floatList().lastFloat()) {
auto lastFloatIterator = floatingObjectSet.find(lastFloat);
ASSERT(lastFloatIterator != end);
++lastFloatIterator;
it = lastFloatIterator;
}
for (; it != end; ++it) {
auto& floatingObject = *it;
appendFloatingObjectToLastLine(*floatingObject);
// If a float's geometry has changed, give up on syncing with clean lines.
auto* floatWithRect = layoutState.floatList().floatWithRect(floatingObject->renderer());
if (!floatWithRect || floatWithRect->rect() != floatingObject->frameRect())
checkForEndLineMatch = false;
}
layoutState.floatList().setLastFloat(!floatingObjectSet.isEmpty() ? floatingObjectSet.last().get() : nullptr);
}
lineWhitespaceCollapsingState.reset();
resolver.setPosition(end, numberOfIsolateAncestors(end));
}
// In case we already adjusted the line positions during this layout to avoid widows
// then we need to ignore the possibility of having a new widows situation.
// Otherwise, we risk leaving empty containers which is against the block fragmentation principles.
if (paginated && !style().hasAutoWidows() && !m_flow.didBreakAtLineToAvoidWidow()) {
// Check the line boxes to make sure we didn't create unacceptable widows.
// However, we'll prioritize orphans - so nothing we do here should create
// a new orphan.
LegacyRootInlineBox* lineBox = lastRootBox();
// Count from the end of the block backwards, to see how many hanging
// lines we have.
LegacyRootInlineBox* firstLineInBlock = firstRootBox();
int numLinesHanging = 1;
while (lineBox && lineBox != firstLineInBlock && !lineBox->isFirstAfterPageBreak()) {
++numLinesHanging;
lineBox = lineBox->prevRootBox();
}
// If there were no breaks in the block, we didn't create any widows.
if (!lineBox || !lineBox->isFirstAfterPageBreak() || lineBox == firstLineInBlock) {
if (m_flow.shouldBreakAtLineToAvoidWidow()) {
// This is the case when the previous line layout marks a line to break at to avoid widows
// but the current layout does not produce that line. It happens when layout constraints unexpectedly
// change in between layouts (note that these paginated line layouts run within the same layout frame
// as opposed to two subsequent full layouts).
ASSERT_NOT_REACHED();
m_flow.clearShouldBreakAtLineToAvoidWidow();
}
return;
}
if (numLinesHanging < style().widows()) {
// We have detected a widow. Now we need to work out how many
// lines there are on the previous page, and how many we need
// to steal.
int numLinesNeeded = style().widows() - numLinesHanging;
LegacyRootInlineBox* currentFirstLineOfNewPage = lineBox;
// Count the number of lines in the previous page.
lineBox = lineBox->prevRootBox();
int numLinesInPreviousPage = 1;
while (lineBox && lineBox != firstLineInBlock && !lineBox->isFirstAfterPageBreak()) {
++numLinesInPreviousPage;
lineBox = lineBox->prevRootBox();
}
// If there was an explicit value for orphans, respect that. If not, we still
// shouldn't create a situation where we make an orphan bigger than the initial value.
// This means that setting widows implies we also care about orphans, but given
// the specification says the initial orphan value is non-zero, this is ok. The
// author is always free to set orphans explicitly as well.
int orphans = style().hasAutoOrphans() ? style().initialOrphans() : style().orphans();
int numLinesAvailable = numLinesInPreviousPage - orphans;
if (numLinesAvailable <= 0)
return;
int numLinesToTake = std::min(numLinesAvailable, numLinesNeeded);
// Wind back from our first widowed line.
lineBox = currentFirstLineOfNewPage;
for (int i = 0; i < numLinesToTake; ++i)
lineBox = lineBox->prevRootBox();
// We now want to break at this line. Remember for next layout and trigger relayout.
m_flow.setBreakAtLineToAvoidWidow(lineCountUntil(lineBox));
m_flow.markLinesDirtyInBlockRange(lastRootBox()->lineBoxBottom(), lineBox->lineBoxBottom(), lineBox);
}
}
m_flow.clearDidBreakAtLineToAvoidWidow();
}
void LegacyLineLayout::reattachCleanLineFloats(LegacyRootInlineBox& cleanLine, LayoutUnit delta, bool isFirstCleanLine)
{
auto* cleanLineFloats = cleanLine.floatsPtr();
if (!cleanLineFloats)
return;
for (auto& floatingBox : *cleanLineFloats) {
if (!floatingBox)
continue;
auto* floatingObject = m_flow.insertFloatingObject(*floatingBox);
if (isFirstCleanLine && floatingObject->originatingLine()) {
// Float box does not belong to this line anymore.
ASSERT_WITH_SECURITY_IMPLICATION(cleanLine.prevRootBox() == floatingObject->originatingLine());
cleanLine.removeFloat(*floatingBox);
continue;
}
ASSERT_WITH_SECURITY_IMPLICATION(!floatingObject->originatingLine());
floatingObject->setOriginatingLine(cleanLine);
m_flow.setLogicalHeight(m_flow.logicalTopForChild(*floatingBox) - m_flow.marginBeforeForChild(*floatingBox) + delta);
m_flow.positionNewFloats();
}
}
void LegacyLineLayout::linkToEndLineIfNeeded(LineLayoutState& layoutState)
{
auto* firstCleanLine = layoutState.endLine();
if (firstCleanLine) {
if (layoutState.endLineMatched()) {
bool paginated = layoutContext().layoutState() && layoutContext().layoutState()->isPaginated();
// Attach all the remaining lines, and then adjust their y-positions as needed.
LayoutUnit delta = m_flow.logicalHeight() - layoutState.endLineLogicalTop();
for (auto* line = firstCleanLine; line; line = line->nextRootBox()) {
line->attachLine();
if (paginated) {
delta -= line->paginationStrut();
bool overflowsFragment;
m_flow.adjustLinePositionForPagination(line, delta, overflowsFragment, layoutState.fragmentedFlow());
}
if (delta) {
layoutState.updateRepaintRangeFromBox(line, delta);
line->adjustBlockDirectionPosition(delta);
}
if (layoutState.fragmentedFlow())
updateFragmentForLine(line);
reattachCleanLineFloats(*line, delta, line == firstCleanLine);
}
m_flow.setLogicalHeight(lastRootBox()->lineBoxBottom());
} else {
// Delete all the remaining lines.
deleteLineRange(layoutState, layoutState.endLine());
}
}
if (m_flow.floatingObjects() && (layoutState.checkForFloatsFromLastLine() || m_flow.positionNewFloats()) && lastRootBox()) {
// In case we have a float on the last line, it might not be positioned up to now.
// This has to be done before adding in the bottom border/padding, or the float will
// include the padding incorrectly. -dwh
if (layoutState.checkForFloatsFromLastLine()) {
LayoutUnit bottomVisualOverflow = lastRootBox()->logicalBottomVisualOverflow();
LayoutUnit bottomLayoutOverflow = lastRootBox()->logicalBottomLayoutOverflow();
auto newLineBox = makeUnique<LegacyRootInlineBox>(m_flow);
newLineBox->setIsForTrailingFloats();
auto trailingFloatsLineBox = newLineBox.get();
m_lineBoxes.appendLineBox(WTFMove(newLineBox));
trailingFloatsLineBox->setConstructed();
GlyphOverflowAndFallbackFontsMap textBoxDataMap;
VerticalPositionCache verticalPositionCache;
LayoutUnit blockLogicalHeight = m_flow.logicalHeight();
trailingFloatsLineBox->alignBoxesInBlockDirection(blockLogicalHeight, textBoxDataMap, verticalPositionCache);
trailingFloatsLineBox->setLineTopBottomPositions(blockLogicalHeight, blockLogicalHeight, blockLogicalHeight, blockLogicalHeight);
trailingFloatsLineBox->setPaginatedLineWidth(m_flow.availableLogicalWidthForContent(blockLogicalHeight));
LayoutRect logicalLayoutOverflow(0_lu, blockLogicalHeight, 1_lu, bottomLayoutOverflow - blockLogicalHeight);
LayoutRect logicalVisualOverflow(0_lu, blockLogicalHeight, 1_lu, bottomVisualOverflow - blockLogicalHeight);
trailingFloatsLineBox->setOverflowFromLogicalRects(logicalLayoutOverflow, logicalVisualOverflow, trailingFloatsLineBox->lineTop(), trailingFloatsLineBox->lineBottom());
if (layoutState.fragmentedFlow())
updateFragmentForLine(trailingFloatsLineBox);
}
const FloatingObjectSet& floatingObjectSet = m_flow.floatingObjects()->set();
auto it = floatingObjectSet.begin();
auto end = floatingObjectSet.end();
if (auto* lastFloat = layoutState.floatList().lastFloat()) {
auto lastFloatIterator = floatingObjectSet.find(lastFloat);
ASSERT(lastFloatIterator != end);
++lastFloatIterator;
it = lastFloatIterator;
}
for (; it != end; ++it)
appendFloatingObjectToLastLine(**it);
layoutState.floatList().setLastFloat(!floatingObjectSet.isEmpty() ? floatingObjectSet.last().get() : nullptr);
}
}
void LegacyLineLayout::layoutLineBoxes(bool relayoutChildren, LayoutUnit& repaintLogicalTop, LayoutUnit& repaintLogicalBottom)
{
m_flow.setLogicalHeight(m_flow.borderAndPaddingBefore());
// Lay out our hypothetical grid line as though it occurs at the top of the block.
if (layoutContext().layoutState() && layoutContext().layoutState()->lineGrid() == &m_flow)
m_flow.layoutLineGridBox();
RenderFragmentedFlow* fragmentedFlow = m_flow.enclosingFragmentedFlow();
bool clearLinesForPagination = firstRootBox() && fragmentedFlow && !fragmentedFlow->hasFragments();
// Figure out if we should clear out our line boxes.
// FIXME: Handle resize eventually!
bool isFullLayout = !firstRootBox() || m_flow.selfNeedsLayout() || relayoutChildren || clearLinesForPagination;
LineLayoutState layoutState(m_flow, isFullLayout, repaintLogicalTop, repaintLogicalBottom, fragmentedFlow);
if (isFullLayout)
lineBoxes().deleteLineBoxes();
// Text truncation kicks in in two cases:
// 1) If your overflow isn't visible and your text-overflow-mode isn't clip.
// 2) If you're an anonymous block with a block parent that satisfies #1.
// FIXME: CSS3 says that descendants that are clipped must also know how to truncate. This is insanely
// difficult to figure out in general (especially in the middle of doing layout), so we only handle the
// simple case of an anonymous block truncating when it's parent is clipped.
auto* parent = m_flow.parent();
bool hasTextOverflow = (style().textOverflow() == TextOverflow::Ellipsis && m_flow.hasNonVisibleOverflow())
|| (m_flow.isAnonymousBlock() && parent && parent->isRenderBlock() && parent->style().textOverflow() == TextOverflow::Ellipsis && parent->hasNonVisibleOverflow());
// Walk all the lines and delete our ellipsis line boxes if they exist.
if (hasTextOverflow)
deleteEllipsisLineBoxes();
if (m_flow.firstChild()) {
// In full layout mode, clear the line boxes of children upfront. Otherwise,
// siblings can run into stale root lineboxes during layout. Then layout
// the replaced elements later. In partial layout mode, line boxes are not
// deleted and only dirtied. In that case, we can layout the replaced
// elements at the same time.
bool hasInlineChild = false;
Vector<RenderBox*> replacedChildren;
for (InlineWalker walker(m_flow); !walker.atEnd(); walker.advance()) {
RenderObject& o = *walker.current();
if (!hasInlineChild && o.isInline())
hasInlineChild = true;
if (o.isReplaced() || o.isFloating() || o.isOutOfFlowPositioned()) {
RenderBox& box = downcast<RenderBox>(o);
if (relayoutChildren || box.hasRelativeDimensions())
box.setChildNeedsLayout(MarkOnlyThis);
// If relayoutChildren is set and the child has percentage padding or an embedded content box, we also need to invalidate the childs pref widths.
if (relayoutChildren && box.needsPreferredWidthsRecalculation())
box.setPreferredLogicalWidthsDirty(true, MarkOnlyThis);
if (box.isOutOfFlowPositioned())
box.containingBlock()->insertPositionedObject(box);
else if (box.isFloating())
layoutState.floatList().append(FloatWithRect::create(box));
else if (isFullLayout || box.needsLayout()) {
// Replaced element.
if (isFullLayout && is<RenderRubyRun>(box)) {
// FIXME: This resets the overhanging margins that we set during line layout (see computeInlineDirectionPositionsForSegment)
// Find a more suitable place for this.
m_flow.setMarginStartForChild(box, 0);
m_flow.setMarginEndForChild(box, 0);
}
box.dirtyLineBoxes(isFullLayout);
if (isFullLayout)
replacedChildren.append(&box);
else
box.layoutIfNeeded();
}
} else if (o.isTextOrLineBreak() || is<RenderInline>(o)) {
if (layoutState.isFullLayout() || o.selfNeedsLayout())
dirtyLineBoxesForRenderer(o, layoutState.isFullLayout());
o.clearNeedsLayout();
}
}
for (size_t i = 0; i < replacedChildren.size(); i++)
replacedChildren[i]->layoutIfNeeded();
layoutRunsAndFloats(layoutState, hasInlineChild);
}
// Expand the last line to accommodate Ruby and emphasis marks.
int lastLineAnnotationsAdjustment = 0;
if (lastRootBox()) {
LayoutUnit lowestAllowedPosition = std::max(lastRootBox()->lineBottom(), m_flow.logicalHeight() + m_flow.paddingAfter());
if (!style().isFlippedLinesWritingMode())
lastLineAnnotationsAdjustment = lastRootBox()->computeUnderAnnotationAdjustment(lowestAllowedPosition);
else
lastLineAnnotationsAdjustment = lastRootBox()->computeOverAnnotationAdjustment(lowestAllowedPosition);
}
// Now do the handling of the bottom of the block, adding in our bottom border/padding and
// determining the correct collapsed bottom margin information. This collapse is only necessary
// if our last child was an anonymous inline block that might need to propagate margin information out to
// us.
LayoutUnit afterEdge = m_flow.borderAndPaddingAfter() + m_flow.scrollbarLogicalHeight() + lastLineAnnotationsAdjustment;
m_flow.setLogicalHeight(m_flow.logicalHeight() + afterEdge);
if (!firstRootBox() && m_flow.hasLineIfEmpty())
m_flow.setLogicalHeight(m_flow.logicalHeight() + m_flow.lineHeight(true, m_flow.isHorizontalWritingMode() ? HorizontalLine : VerticalLine, PositionOfInteriorLineBoxes));
// See if we have any lines that spill out of our block. If we do, then we will possibly need to
// truncate text.
if (hasTextOverflow)
checkLinesForTextOverflow();
}
void LegacyLineLayout::checkFloatInCleanLine(LegacyRootInlineBox& cleanLine, RenderBox& floatBoxOnCleanLine, FloatWithRect& matchingFloatWithRect,
bool& encounteredNewFloat, bool& dirtiedByFloat)
{
ASSERT_WITH_SECURITY_IMPLICATION(!floatBoxOnCleanLine.style().deletionHasBegun());
if (&matchingFloatWithRect.renderer() != &floatBoxOnCleanLine) {
encounteredNewFloat = true;
return;
}
floatBoxOnCleanLine.layoutIfNeeded();
LayoutRect originalFloatRect = matchingFloatWithRect.rect();
LayoutSize newSize(
floatBoxOnCleanLine.width() + floatBoxOnCleanLine.horizontalMarginExtent(),
floatBoxOnCleanLine.height() + floatBoxOnCleanLine.verticalMarginExtent());
// We have to reset the cap-height alignment done by the first-letter floats when initial-letter is set, so just always treat first-letter floats as dirty.
if (originalFloatRect.size() == newSize && (floatBoxOnCleanLine.style().styleType() != PseudoId::FirstLetter || !floatBoxOnCleanLine.style().initialLetterDrop()))
return;
LayoutUnit floatTop = m_flow.isHorizontalWritingMode() ? originalFloatRect.y() : originalFloatRect.x();
LayoutUnit floatHeight = m_flow.isHorizontalWritingMode() ? std::max(originalFloatRect.height(), newSize.height())
: std::max(originalFloatRect.width(), newSize.width());
floatHeight = std::min(floatHeight, LayoutUnit::max() - floatTop);
cleanLine.markDirty();
m_flow.markLinesDirtyInBlockRange(cleanLine.lineBoxBottom(), floatTop + floatHeight, &cleanLine);
LayoutRect newFloatRect = originalFloatRect;
newFloatRect.setSize(newSize);
matchingFloatWithRect.adjustRect(newFloatRect);
dirtiedByFloat = true;
}
LegacyRootInlineBox* LegacyLineLayout::determineStartPosition(LineLayoutState& layoutState, InlineBidiResolver& resolver)
{
LegacyRootInlineBox* currentLine = nullptr;
LegacyRootInlineBox* lastLine = nullptr;
// FIXME: This entire float-checking block needs to be broken into a new function.
auto& floats = layoutState.floatList();
bool dirtiedByFloat = false;
if (!layoutState.isFullLayout()) {
// Paginate all of the clean lines.
bool paginated = layoutContext().layoutState() && layoutContext().layoutState()->isPaginated();
LayoutUnit paginationDelta;
auto floatsIterator = floats.begin();
auto end = floats.end();
for (currentLine = firstRootBox(); currentLine && !currentLine->isDirty(); currentLine = currentLine->nextRootBox()) {
if (paginated) {
if (lineWidthForPaginatedLineChanged(currentLine, 0, layoutState.fragmentedFlow())) {
currentLine->markDirty();
break;
}
paginationDelta -= currentLine->paginationStrut();
bool overflowsFragment;
m_flow.adjustLinePositionForPagination(currentLine, paginationDelta, overflowsFragment, layoutState.fragmentedFlow());
if (paginationDelta) {
if (m_flow.containsFloats() || !floats.isEmpty()) {
// FIXME: Do better eventually. For now if we ever shift because of pagination and floats are present just go to a full layout.
layoutState.markForFullLayout();
break;
}
layoutState.updateRepaintRangeFromBox(currentLine, paginationDelta);
currentLine->adjustBlockDirectionPosition(paginationDelta);
}
if (layoutState.fragmentedFlow())
updateFragmentForLine(currentLine);
}
if (auto* cleanLineFloats = currentLine->floatsPtr()) {
// If a new float has been inserted before this line or before its last known float, just do a full layout.
bool encounteredNewFloat = false;
for (auto& floatBoxOnCleanLine : *cleanLineFloats) {
ASSERT(floatsIterator != end);
if (!floatBoxOnCleanLine)
continue;
checkFloatInCleanLine(*currentLine, *floatBoxOnCleanLine, *floatsIterator, encounteredNewFloat, dirtiedByFloat);
++floatsIterator;
if (floatsIterator == end || encounteredNewFloat) {
layoutState.markForFullLayout();
break;
}
}
if (dirtiedByFloat || encounteredNewFloat)
break;
}
}
// Check if a new float has been inserted after the last known float.
if (floatsIterator != end) {
if (!currentLine)
layoutState.markForFullLayout();
else {
for (; floatsIterator != end; ++floatsIterator) {
auto& floatWithRect = *floatsIterator;
if (!floatWithRect->renderer().needsLayout())
continue;
layoutState.markForFullLayout();
break;
}
}
}
}
if (layoutState.isFullLayout()) {
m_lineBoxes.deleteLineBoxTree();
currentLine = nullptr;
ASSERT(!firstRootBox() && !lastRootBox());
} else {
if (currentLine) {
// We have a dirty line.
if (LegacyRootInlineBox* prevRootBox = currentLine->prevRootBox()) {
// We have a previous line.
if (!dirtiedByFloat && (!prevRootBox->endsWithBreak()
|| !prevRootBox->lineBreakObj()
|| (is<RenderText>(*prevRootBox->lineBreakObj())
&& prevRootBox->lineBreakPos() >= downcast<RenderText>(*prevRootBox->lineBreakObj()).text().length()))) {
// The previous line didn't break cleanly or broke at a newline
// that has been deleted, so treat it as dirty too.
currentLine = prevRootBox;
}
}
}
// If we have no dirty lines, then last is just the last root box.
lastLine = currentLine ? currentLine->prevRootBox() : lastRootBox();
}
if (!floats.isEmpty()) {
LayoutUnit savedLogicalHeight = m_flow.logicalHeight();
// Restore floats from clean lines.
LegacyRootInlineBox* line = firstRootBox();
while (line != currentLine) {
if (auto* cleanLineFloats = line->floatsPtr()) {
for (auto& floatingBox : *cleanLineFloats) {
if (!floatingBox)
continue;
auto* floatingObject = m_flow.insertFloatingObject(*floatingBox);
ASSERT_WITH_SECURITY_IMPLICATION(!floatingObject->originatingLine());
floatingObject->setOriginatingLine(*line);
m_flow.setLogicalHeight(m_flow.logicalTopForChild(*floatingBox) - m_flow.marginBeforeForChild(*floatingBox));
m_flow.positionNewFloats();
floats.setLastCleanFloat(*floatingBox);
}
}
line = line->nextRootBox();
}
m_flow.setLogicalHeight(savedLogicalHeight);
}
layoutState.lineInfo().setFirstLine(!lastLine);
layoutState.lineInfo().setPreviousLineBrokeCleanly(!lastLine || lastLine->endsWithBreak());
if (lastLine) {
m_flow.setLogicalHeight(lastLine->lineBoxBottom());
LegacyInlineIterator iter = LegacyInlineIterator(&m_flow, lastLine->lineBreakObj(), lastLine->lineBreakPos());
resolver.setPosition(iter, numberOfIsolateAncestors(iter));
resolver.setStatus(lastLine->lineBreakBidiStatus());
} else {
TextDirection direction = style().direction();
if (style().unicodeBidi() == Plaintext)
determineDirectionality(direction, LegacyInlineIterator(&m_flow, firstInlineRendererSkippingEmpty(m_flow), 0));
resolver.setStatus(BidiStatus(direction, isOverride(style().unicodeBidi())));
LegacyInlineIterator iter = LegacyInlineIterator(&m_flow, firstInlineRendererSkippingEmpty(m_flow, &resolver), 0);
resolver.setPosition(iter, numberOfIsolateAncestors(iter));
}
return currentLine;
}
void LegacyLineLayout::determineEndPosition(LineLayoutState& layoutState, LegacyRootInlineBox* startLine, LegacyInlineIterator& cleanLineStart, BidiStatus& cleanLineBidiStatus)
{
auto iteratorForFirstDirtyFloat = [](LineLayoutState::FloatList& floats) {
auto lastCleanFloat = floats.lastCleanFloat();
if (!lastCleanFloat)
return floats.begin();
auto* lastCleanFloatWithRect = floats.floatWithRect(*lastCleanFloat);
ASSERT(lastCleanFloatWithRect);
return ++floats.find(*lastCleanFloatWithRect);
};
ASSERT(!layoutState.endLine());
auto floatsIterator = iteratorForFirstDirtyFloat(layoutState.floatList());
auto end = layoutState.floatList().end();
LegacyRootInlineBox* lastLine = nullptr;
for (auto* currentLine = startLine->nextRootBox(); currentLine; currentLine = currentLine->nextRootBox()) {
if (!currentLine->isDirty()) {
if (auto* cleanLineFloats = currentLine->floatsPtr()) {
bool encounteredNewFloat = false;
bool dirtiedByFloat = false;
for (auto& floatBoxOnCleanLine : *cleanLineFloats) {
if (!floatBoxOnCleanLine)
continue;
ASSERT(floatsIterator != end);
checkFloatInCleanLine(*currentLine, *floatBoxOnCleanLine, *floatsIterator, encounteredNewFloat, dirtiedByFloat);
++floatsIterator;
if (floatsIterator == end || encounteredNewFloat)
return;
}
}
}
if (currentLine->isDirty())
lastLine = nullptr;
else if (!lastLine)
lastLine = currentLine;
}
if (!lastLine)
return;
// At this point, |last| is the first line in a run of clean lines that ends with the last line
// in the block.
LegacyRootInlineBox* previousLine = lastLine->prevRootBox();
cleanLineStart = LegacyInlineIterator(&m_flow, previousLine->lineBreakObj(), previousLine->lineBreakPos());
cleanLineBidiStatus = previousLine->lineBreakBidiStatus();
layoutState.setEndLineLogicalTop(previousLine->lineBoxBottom());
for (auto* line = lastLine; line; line = line->nextRootBox()) {
// Disconnect all line boxes from their render objects while preserving their connections to one another.
line->extractLine();
}
layoutState.setEndLine(lastLine);
}
bool LegacyLineLayout::checkPaginationAndFloatsAtEndLine(LineLayoutState& layoutState)
{
LayoutUnit lineDelta = m_flow.logicalHeight() - layoutState.endLineLogicalTop();
bool paginated = layoutContext().layoutState() && layoutContext().layoutState()->isPaginated();
if (paginated && layoutState.fragmentedFlow()) {
// Check all lines from here to the end, and see if the hypothetical new position for the lines will result
// in a different available line width.
for (auto* lineBox = layoutState.endLine(); lineBox; lineBox = lineBox->nextRootBox()) {
if (paginated) {
// This isn't the real move we're going to do, so don't update the line box's pagination
// strut yet.
LayoutUnit oldPaginationStrut = lineBox->paginationStrut();
bool overflowsFragment;
lineDelta -= oldPaginationStrut;
m_flow.adjustLinePositionForPagination(lineBox, lineDelta, overflowsFragment, layoutState.fragmentedFlow());
lineBox->setPaginationStrut(oldPaginationStrut);
}
if (lineWidthForPaginatedLineChanged(lineBox, lineDelta, layoutState.fragmentedFlow()))
return false;
}
}
if (!lineDelta || !m_flow.floatingObjects())
return true;
// See if any floats end in the range along which we want to shift the lines vertically.
LayoutUnit logicalTop = std::min(m_flow.logicalHeight(), layoutState.endLineLogicalTop());
LegacyRootInlineBox* lastLine = layoutState.endLine();
while (LegacyRootInlineBox* nextLine = lastLine->nextRootBox())
lastLine = nextLine;
LayoutUnit logicalBottom = lastLine->lineBoxBottom() + absoluteValue(lineDelta);
const FloatingObjectSet& floatingObjectSet = m_flow.floatingObjects()->set();
auto end = floatingObjectSet.end();
for (auto it = floatingObjectSet.begin(); it != end; ++it) {
const auto& floatingObject = *it->get();
if (m_flow.logicalBottomForFloat(floatingObject) >= logicalTop && m_flow.logicalBottomForFloat(floatingObject) < logicalBottom)
return false;
}
return true;
}
bool LegacyLineLayout::lineWidthForPaginatedLineChanged(LegacyRootInlineBox* rootBox, LayoutUnit lineDelta, RenderFragmentedFlow* fragmentedFlow) const
{
if (!fragmentedFlow)
return false;
RenderFragmentContainer* currentFragment = m_flow.fragmentAtBlockOffset(rootBox->lineBoxTop() + lineDelta);
// Just bail if the fragment didn't change.
if (rootBox->containingFragment() == currentFragment)
return false;
return rootBox->paginatedLineWidth() != m_flow.availableLogicalWidthForContent(currentFragment);
}
bool LegacyLineLayout::matchedEndLine(LineLayoutState& layoutState, const InlineBidiResolver& resolver, const LegacyInlineIterator& endLineStart, const BidiStatus& endLineStatus)
{
if (resolver.position() == endLineStart) {
if (resolver.status() != endLineStatus)
return false;
return checkPaginationAndFloatsAtEndLine(layoutState);
}
// The first clean line doesn't match, but we can check a handful of following lines to try
// to match back up.
static const int numLines = 8; // The # of lines we're willing to match against.
LegacyRootInlineBox* originalEndLine = layoutState.endLine();
LegacyRootInlineBox* line = originalEndLine;
for (int i = 0; i < numLines && line; i++, line = line->nextRootBox()) {
if (line->lineBreakObj() == resolver.position().renderer() && line->lineBreakPos() == resolver.position().offset()) {
// We have a match.
if (line->lineBreakBidiStatus() != resolver.status())
return false; // ...but the bidi state doesn't match.
bool matched = false;
LegacyRootInlineBox* result = line->nextRootBox();
layoutState.setEndLine(result);
if (result) {
layoutState.setEndLineLogicalTop(line->lineBoxBottom());
matched = checkPaginationAndFloatsAtEndLine(layoutState);
}
// Now delete the lines that we failed to sync.
deleteLineRange(layoutState, originalEndLine, result);
return matched;
}
}
return false;
}
void LegacyLineLayout::addOverflowFromInlineChildren()
{
LayoutUnit endPadding = m_flow.hasNonVisibleOverflow() ? m_flow.paddingEnd() : 0_lu;
// FIXME: Need to find another way to do this, since scrollbars could show when we don't want them to.
if (!endPadding)
endPadding = m_flow.endPaddingWidthForCaret();
if (m_flow.hasNonVisibleOverflow() && !endPadding && m_flow.element() && m_flow.element()->isRootEditableElement() && style().isLeftToRightDirection())
endPadding = 1;
for (auto* curr = firstRootBox(); curr; curr = curr->nextRootBox()) {
m_flow.addLayoutOverflow(curr->paddedLayoutOverflowRect(endPadding));
RenderFragmentContainer* fragment = m_flow.enclosingFragmentedFlow() ? curr->containingFragment() : nullptr;
if (fragment)
fragment->addLayoutOverflowForBox(&m_flow, curr->paddedLayoutOverflowRect(endPadding));
if (!m_flow.hasNonVisibleOverflow()) {
LayoutRect childVisualOverflowRect = curr->visualOverflowRect(curr->lineTop(), curr->lineBottom());
m_flow.addVisualOverflow(childVisualOverflowRect);
if (fragment)
fragment->addVisualOverflowForBox(&m_flow, childVisualOverflowRect);
}
}
}
size_t LegacyLineLayout::lineCount() const
{
size_t count = 0;
for (auto* box = firstRootBox(); box; box = box->nextRootBox())
++count;
return count;
}
size_t LegacyLineLayout::lineCountUntil(const LegacyRootInlineBox* stopRootInlineBox) const
{
size_t count = 0;
for (auto* box = firstRootBox(); box; box = box->nextRootBox()) {
++count;
if (box == stopRootInlineBox)
break;
}
return count;
}
void LegacyLineLayout::deleteEllipsisLineBoxes()
{
TextAlignMode textAlign = style().textAlign();
bool ltr = style().isLeftToRightDirection();
IndentTextOrNot shouldIndentText = IndentText;
for (auto* curr = firstRootBox(); curr; curr = curr->nextRootBox()) {
if (curr->hasEllipsisBox()) {
curr->clearTruncation();
// Shift the line back where it belongs if we cannot accomodate an ellipsis.
float logicalLeft = m_flow.logicalLeftOffsetForLine(curr->lineTop(), shouldIndentText);
float availableLogicalWidth = m_flow.logicalRightOffsetForLine(curr->lineTop(), DoNotIndentText) - logicalLeft;
float totalLogicalWidth = curr->logicalWidth();
updateLogicalWidthForAlignment(m_flow, textAlign, curr, 0, logicalLeft, totalLogicalWidth, availableLogicalWidth, 0);
if (ltr)
curr->adjustLogicalPosition((logicalLeft - curr->logicalLeft()), 0);
else
curr->adjustLogicalPosition(-(curr->logicalLeft() - logicalLeft), 0);
}
shouldIndentText = DoNotIndentText;
}
}
void LegacyLineLayout::checkLinesForTextOverflow()
{
// Determine the width of the ellipsis using the current font.
// FIXME: CSS3 says this is configurable, also need to use 0x002E (FULL STOP) if horizontal ellipsis is "not renderable"
const FontCascade& font = style().fontCascade();
static MainThreadNeverDestroyed<const AtomString> ellipsisStr(&horizontalEllipsis, 1);
const FontCascade& firstLineFont = m_flow.firstLineStyle().fontCascade();
float firstLineEllipsisWidth = firstLineFont.width(m_flow.constructTextRun(&horizontalEllipsis, 1, m_flow.firstLineStyle()));
float ellipsisWidth = (font == firstLineFont) ? firstLineEllipsisWidth : font.width(m_flow.constructTextRun(&horizontalEllipsis, 1, style()));
// For LTR text truncation, we want to get the right edge of our padding box, and then we want to see
// if the right edge of a line box exceeds that. For RTL, we use the left edge of the padding box and
// check the left edge of the line box to see if it is less
// Include the scrollbar for overflow blocks, which means we want to use "contentWidth()"
bool ltr = style().isLeftToRightDirection();
TextAlignMode textAlign = style().textAlign();
bool firstLine = true;
for (auto* curr = firstRootBox(); curr; curr = curr->nextRootBox()) {
IndentTextOrNot shouldIndentText = firstLine ? IndentText : DoNotIndentText;
LayoutUnit blockRightEdge = m_flow.logicalRightOffsetForLine(curr->lineTop(), shouldIndentText);
LayoutUnit blockLeftEdge = m_flow.logicalLeftOffsetForLine(curr->lineTop(), shouldIndentText);
LayoutUnit lineBoxEdge { ltr ? curr->x() + curr->logicalWidth() : curr->x() };
if ((ltr && lineBoxEdge > blockRightEdge) || (!ltr && lineBoxEdge < blockLeftEdge)) {
// This line spills out of our box in the appropriate direction. Now we need to see if the line
// can be truncated. In order for truncation to be possible, the line must have sufficient space to
// accommodate our truncation string, and no replaced elements (images, tables) can overlap the ellipsis
// space.
LayoutUnit width { firstLine ? firstLineEllipsisWidth : ellipsisWidth };
LayoutUnit blockEdge { ltr ? blockRightEdge : blockLeftEdge };
if (curr->lineCanAccommodateEllipsis(ltr, blockEdge, lineBoxEdge, width)) {
float totalLogicalWidth = curr->placeEllipsis(ellipsisStr, ltr, blockLeftEdge, blockRightEdge, width);
float logicalLeft = 0; // We are only interested in the delta from the base position.
float truncatedWidth = m_flow.availableLogicalWidthForLine(curr->lineTop(), shouldIndentText);
updateLogicalWidthForAlignment(m_flow, textAlign, curr, nullptr, logicalLeft, totalLogicalWidth, truncatedWidth, 0);
if (ltr)
curr->adjustLogicalPosition(logicalLeft, 0);
else
curr->adjustLogicalPosition(-(truncatedWidth - (logicalLeft + totalLogicalWidth)), 0);
}
}
firstLine = false;
}
}
bool LegacyLineLayout::positionNewFloatOnLine(const FloatingObject& newFloat, FloatingObject* lastFloatFromPreviousLine, LineInfo& lineInfo, LineWidth& width)
{
if (!m_flow.positionNewFloats())
return false;
width.shrinkAvailableWidthForNewFloatIfNeeded(newFloat);
// We only connect floats to lines for pagination purposes if the floats occur at the start of
// the line and the previous line had a hard break (so this line is either the first in the block
// or follows a <br>).
if (!newFloat.paginationStrut() || !lineInfo.previousLineBrokeCleanly() || !lineInfo.isEmpty())
return true;
const FloatingObjectSet& floatingObjectSet = m_flow.floatingObjects()->set();
ASSERT(floatingObjectSet.last().get() == &newFloat);
LayoutUnit floatLogicalTop = m_flow.logicalTopForFloat(newFloat);
LayoutUnit paginationStrut = newFloat.paginationStrut();
if (floatLogicalTop - paginationStrut != m_flow.logicalHeight() + lineInfo.floatPaginationStrut())
return true;
auto it = floatingObjectSet.end();
--it; // Last float is newFloat, skip that one.
auto begin = floatingObjectSet.begin();
while (it != begin) {
--it;
auto& floatingObject = *it->get();
if (&floatingObject == lastFloatFromPreviousLine)
break;
if (m_flow.logicalTopForFloat(floatingObject) == m_flow.logicalHeight() + lineInfo.floatPaginationStrut()) {
floatingObject.setPaginationStrut(paginationStrut + floatingObject.paginationStrut());
RenderBox& floatBox = floatingObject.renderer();
m_flow.setLogicalTopForChild(floatBox, m_flow.logicalTopForChild(floatBox) + m_flow.marginBeforeForChild(floatBox) + paginationStrut);
if (m_flow.updateFragmentRangeForBoxChild(floatBox))
floatBox.setNeedsLayout(MarkOnlyThis);
else if (is<RenderBlock>(floatBox))
downcast<RenderBlock>(floatBox).setChildNeedsLayout(MarkOnlyThis);
floatBox.layoutIfNeeded();
// Save the old logical top before calling removePlacedObject which will set
// isPlaced to false. Otherwise it will trigger an assert in logicalTopForFloat.
LayoutUnit oldLogicalTop = m_flow.logicalTopForFloat(floatingObject);
m_flow.floatingObjects()->removePlacedObject(&floatingObject);
m_flow.setLogicalTopForFloat(floatingObject, oldLogicalTop + paginationStrut);
m_flow.floatingObjects()->addPlacedObject(&floatingObject);
}
}
// Just update the line info's pagination strut without altering our logical height yet. If the line ends up containing
// no content, then we don't want to improperly grow the height of the block.
lineInfo.setFloatPaginationStrut(lineInfo.floatPaginationStrut() + paginationStrut);
return true;
}
void LegacyLineLayout::updateFragmentForLine(LegacyRootInlineBox* lineBox) const
{
ASSERT(lineBox);
if (!m_flow.hasFragmentRangeInFragmentedFlow())
lineBox->clearContainingFragment();
else {
if (auto containingFragment = m_flow.fragmentAtBlockOffset(lineBox->lineBoxTop()))
lineBox->setContainingFragment(*containingFragment);
else
lineBox->clearContainingFragment();
}
LegacyRootInlineBox* prevLineBox = lineBox->prevRootBox();
if (!prevLineBox)
return;
// This check is more accurate than the one in |adjustLinePositionForPagination| because it takes into
// account just the container changes between lines. The before mentioned function doesn't set the flag
// correctly if the line is positioned at the top of the last fragment container.
if (lineBox->containingFragment() != prevLineBox->containingFragment())
lineBox->setIsFirstAfterPageBreak(true);
}
const RenderStyle& LegacyLineLayout::style() const
{
return m_flow.style();
}
const FrameViewLayoutContext& LegacyLineLayout::layoutContext() const
{
return m_flow.view().frameView().layoutContext();
}
}