| /* |
| * Copyright (C) 2000 Lars Knoll (knoll@kde.org) |
| * Copyright (C) 2003, 2004, 2006, 2007, 2008, 2009, 2010, 2011 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. |
| * |
| */ |
| |
| #pragma once |
| |
| #include "BreakLines.h" |
| #include "Hyphenation.h" |
| #include "LineBreaker.h" |
| #include "LineInfo.h" |
| #include "LineLayoutState.h" |
| #include "LineWidth.h" |
| #include "RenderCombineText.h" |
| #include "RenderCounter.h" |
| #include "RenderInline.h" |
| #include "RenderLayer.h" |
| #include "RenderLineBreak.h" |
| #include "RenderListMarker.h" |
| #include "RenderRubyRun.h" |
| #include "RenderSVGInlineText.h" |
| #include "TrailingObjects.h" |
| #include <wtf/Function.h> |
| #include <wtf/Optional.h> |
| #include <wtf/text/StringView.h> |
| #include <wtf/unicode/CharacterNames.h> |
| |
| namespace WebCore { |
| |
| // We don't let our line box tree for a single line get any deeper than this. |
| const unsigned cMaxLineDepth = 200; |
| |
| struct WordMeasurement { |
| WordMeasurement() |
| : renderer(0) |
| , width(0) |
| , startOffset(0) |
| , endOffset(0) |
| { |
| } |
| |
| RenderText* renderer; |
| float width; |
| unsigned startOffset; |
| unsigned endOffset; |
| HashSet<const Font*> fallbackFonts; |
| }; |
| |
| struct WordTrailingSpace { |
| WordTrailingSpace(const RenderStyle& style, bool measuringWithTrailingWhitespaceEnabled = true) |
| : m_style(style) |
| { |
| if (!measuringWithTrailingWhitespaceEnabled || !m_style.fontCascade().enableKerning()) |
| m_state = WordTrailingSpaceState::Initialized; |
| } |
| |
| Optional<float> width(HashSet<const Font*>& fallbackFonts) |
| { |
| if (m_state == WordTrailingSpaceState::Initialized) |
| return m_width; |
| |
| auto& font = m_style.fontCascade(); |
| m_width = font.width(RenderBlock::constructTextRun(&space, 1, m_style), &fallbackFonts) + font.wordSpacing(); |
| m_state = WordTrailingSpaceState::Initialized; |
| return m_width; |
| } |
| |
| private: |
| enum class WordTrailingSpaceState { Uninitialized, Initialized }; |
| const RenderStyle& m_style; |
| WordTrailingSpaceState m_state { WordTrailingSpaceState::Uninitialized }; |
| Optional<float> m_width; |
| }; |
| |
| class BreakingContext { |
| public: |
| BreakingContext(LineBreaker& lineBreaker, InlineBidiResolver& resolver, LineInfo& inLineInfo, LineWidth& lineWidth, RenderTextInfo& inRenderTextInfo, FloatingObject* inLastFloatFromPreviousLine, bool appliedStartWidth, RenderBlockFlow& block) |
| : m_lineBreaker(lineBreaker) |
| , m_resolver(resolver) |
| , m_current(resolver.position()) |
| , m_lineBreak(resolver.position()) |
| , m_block(block) |
| , m_lastObject(m_current.renderer()) |
| , m_nextObject(nullptr) |
| , m_currentStyle(nullptr) |
| , m_blockStyle(block.style()) |
| , m_lineInfo(inLineInfo) |
| , m_renderTextInfo(inRenderTextInfo) |
| , m_lastFloatFromPreviousLine(inLastFloatFromPreviousLine) |
| , m_width(lineWidth) |
| , m_currWS(WhiteSpace::Normal) |
| , m_lastWS(WhiteSpace::Normal) |
| , m_preservesNewline(false) |
| , m_atStart(true) |
| , m_ignoringSpaces(false) |
| , m_currentCharacterIsSpace(false) |
| , m_currentCharacterIsWS(false) |
| , m_hasFormerOpportunity(false) |
| , m_appliedStartWidth(appliedStartWidth) |
| , m_includeEndWidth(true) |
| , m_autoWrap(false) |
| , m_autoWrapWasEverTrueOnLine(false) |
| , m_floatsFitOnLine(true) |
| , m_collapseWhiteSpace(false) |
| , m_startingNewParagraph(m_lineInfo.previousLineBrokeCleanly()) |
| , m_allowImagesToBreak(!block.document().inQuirksMode() || !block.isTableCell() || !m_blockStyle.logicalWidth().isIntrinsicOrAuto()) |
| , m_atEnd(false) |
| , m_hadUncommittedWidthBeforeCurrent(false) |
| , m_lineWhitespaceCollapsingState(resolver.whitespaceCollapsingState()) |
| { |
| m_lineInfo.setPreviousLineBrokeCleanly(false); |
| } |
| |
| RenderObject* currentObject() { return m_current.renderer(); } |
| InlineIterator lineBreak() { return m_lineBreak; } |
| LineWidth& lineWidth() { return m_width; } |
| bool atEnd() { return m_atEnd; } |
| |
| bool fitsOnLineOrHangsAtEnd() const { return m_width.fitsOnLine() || m_hangsAtEnd; } |
| |
| void initializeForCurrentObject(); |
| |
| void increment(); |
| |
| void handleBR(Clear&); |
| void handleOutOfFlowPositioned(Vector<RenderBox*>& positionedObjects); |
| void handleFloat(); |
| void handleEmptyInline(); |
| void handleReplaced(); |
| bool handleText(WordMeasurements&, bool& hyphenated, unsigned& consecutiveHyphenatedLines); |
| void trailingSpacesHang(InlineIterator&, RenderObject&, bool canBreakMidWord, bool previousCharacterIsSpace); |
| bool canBreakAtThisPosition(); |
| void commitAndUpdateLineBreakIfNeeded(); |
| InlineIterator handleEndOfLine(); |
| |
| float computeAdditionalBetweenWordsWidth(RenderText&, TextLayout*, UChar, WordTrailingSpace&, HashSet<const Font*>& fallbackFonts, WordMeasurements&, const FontCascade&, bool isFixedPitch, unsigned lastSpace, float lastSpaceWordSpacing, float wordSpacingForWordMeasurement, unsigned offset); |
| |
| void clearLineBreakIfFitsOnLine(bool ignoringTrailingSpace = false) |
| { |
| if (m_width.fitsOnLine(ignoringTrailingSpace) || m_lastWS == WhiteSpace::NoWrap || m_hangsAtEnd) |
| m_lineBreak.clear(); |
| m_hangsAtEnd = false; |
| } |
| |
| void commitLineBreakClear() |
| { |
| m_width.commit(); |
| m_lineBreak.clear(); |
| m_hangsAtEnd = false; |
| } |
| |
| void commitLineBreakAtCurrentWidth(RenderObject& object, unsigned offset = 0, Optional<unsigned> nextBreak = Optional<unsigned>()) |
| { |
| m_width.commit(); |
| m_lineBreak.moveTo(object, offset, nextBreak); |
| m_hangsAtEnd = false; |
| } |
| |
| private: |
| LineBreaker& m_lineBreaker; |
| InlineBidiResolver& m_resolver; |
| |
| InlineIterator m_current; |
| InlineIterator m_lineBreak; |
| InlineIterator m_startOfIgnoredSpaces; |
| |
| RenderBlockFlow& m_block; |
| RenderObject* m_lastObject; |
| RenderObject* m_nextObject; |
| |
| const RenderStyle* m_currentStyle; |
| |
| // Firefox and Opera will allow a table cell to grow to fit an image inside it under |
| // very specific circumstances (in order to match common WinIE renderings). |
| // Not supporting the quirk has caused us to mis-render some real sites. (See Bugzilla 10517.) |
| const RenderStyle& m_blockStyle; |
| |
| LineInfo& m_lineInfo; |
| |
| RenderTextInfo& m_renderTextInfo; |
| |
| FloatingObject* m_lastFloatFromPreviousLine; |
| |
| LineWidth m_width; |
| |
| WhiteSpace m_currWS; |
| WhiteSpace m_lastWS; |
| |
| bool m_preservesNewline; |
| bool m_atStart; |
| |
| // This variable is used only if whitespace isn't set to WhiteSpace::Pre, and it tells us whether |
| // or not we are currently ignoring whitespace. |
| bool m_ignoringSpaces; |
| |
| // This variable tracks whether the very last character we saw was a space. We use |
| // this to detect when we encounter a second space so we know we have to terminate |
| // a run. |
| bool m_currentCharacterIsSpace; |
| bool m_currentCharacterIsWS; |
| bool m_hasFormerOpportunity; |
| bool m_appliedStartWidth; |
| bool m_includeEndWidth; |
| bool m_autoWrap; |
| bool m_autoWrapWasEverTrueOnLine; |
| bool m_floatsFitOnLine; |
| bool m_collapseWhiteSpace; |
| bool m_startingNewParagraph; |
| bool m_allowImagesToBreak; |
| bool m_atEnd; |
| bool m_hadUncommittedWidthBeforeCurrent; |
| |
| bool m_hangsAtEnd { false }; |
| |
| LineWhitespaceCollapsingState& m_lineWhitespaceCollapsingState; |
| |
| TrailingObjects m_trailingObjects; |
| }; |
| |
| inline void BreakingContext::initializeForCurrentObject() |
| { |
| m_hadUncommittedWidthBeforeCurrent = !!m_width.uncommittedWidth(); |
| |
| m_currentStyle = &m_current.renderer()->style(); // FIXME: Should this be &lineStyle(*m_current.renderer(), m_lineInfo); ? |
| |
| ASSERT(m_currentStyle); |
| |
| m_nextObject = bidiNextSkippingEmptyInlines(m_block, m_current.renderer()); |
| if (m_nextObject && m_nextObject->parent() && !m_nextObject->parent()->isDescendantOf(m_current.renderer()->parent())) |
| m_includeEndWidth = true; |
| |
| m_currWS = m_current.renderer()->isReplaced() ? m_current.renderer()->parent()->style().whiteSpace() : m_currentStyle->whiteSpace(); |
| m_lastWS = m_lastObject->isReplaced() ? m_lastObject->parent()->style().whiteSpace() : m_lastObject->style().whiteSpace(); |
| |
| m_autoWrap = RenderStyle::autoWrap(m_currWS); |
| m_autoWrapWasEverTrueOnLine = m_autoWrapWasEverTrueOnLine || m_autoWrap; |
| |
| m_preservesNewline = m_current.renderer()->isSVGInlineText() ? false : RenderStyle::preserveNewline(m_currWS); |
| |
| m_collapseWhiteSpace = RenderStyle::collapseWhiteSpace(m_currWS); |
| } |
| |
| inline void BreakingContext::increment() |
| { |
| // Clear out our character space bool, since inline <pre>s don't collapse whitespace |
| // with adjacent inline normal/nowrap spans. |
| if (!m_collapseWhiteSpace) |
| m_currentCharacterIsSpace = false; |
| |
| if (m_nextObject) |
| m_current.moveToStartOf(*m_nextObject); |
| else |
| m_current.clear(); |
| m_atStart = false; |
| } |
| |
| inline void BreakingContext::handleBR(Clear& clear) |
| { |
| if (fitsOnLineOrHangsAtEnd()) { |
| RenderObject& br = *m_current.renderer(); |
| m_lineBreak.moveToStartOf(br); |
| m_lineBreak.increment(); |
| |
| // A <br> always breaks a line, so don't let the line be collapsed |
| // away. Also, the space at the end of a line with a <br> does not |
| // get collapsed away. It only does this if the previous line broke |
| // cleanly. Otherwise the <br> has no effect on whether the line is |
| // empty or not. |
| if (m_startingNewParagraph) |
| m_lineInfo.setEmpty(false, &m_block, &m_width); |
| m_trailingObjects.clear(); |
| m_lineInfo.setPreviousLineBrokeCleanly(true); |
| |
| // A <br> with clearance always needs a linebox in case the lines below it get dirtied later and |
| // need to check for floats to clear - so if we're ignoring spaces, stop ignoring them and add a |
| // run for this object. |
| if (m_ignoringSpaces && m_currentStyle->clear() != Clear::None) |
| m_lineWhitespaceCollapsingState.ensureLineBoxInsideIgnoredSpaces(br); |
| // If we were preceded by collapsing space and are in a right-aligned container we need to ensure the space gets |
| // collapsed away so that it doesn't push the text out from the container's right-hand edge. |
| // FIXME: Do this regardless of the container's alignment - will require rebaselining a lot of test results. |
| else if (m_ignoringSpaces && (m_blockStyle.textAlign() == TextAlignMode::Right || m_blockStyle.textAlign() == TextAlignMode::WebKitRight)) |
| m_lineWhitespaceCollapsingState.stopIgnoringSpaces(InlineIterator(0, m_current.renderer(), m_current.offset())); |
| |
| if (!m_lineInfo.isEmpty()) |
| clear = m_currentStyle->clear(); |
| } |
| m_atEnd = true; |
| } |
| |
| inline LayoutUnit borderPaddingMarginStart(const RenderInline& child) |
| { |
| return child.marginStart() + child.paddingStart() + child.borderStart(); |
| } |
| |
| inline LayoutUnit borderPaddingMarginEnd(const RenderInline& child) |
| { |
| return child.marginEnd() + child.paddingEnd() + child.borderEnd(); |
| } |
| |
| inline bool shouldAddBorderPaddingMargin(RenderObject* child) |
| { |
| if (!child) |
| return true; |
| // When deciding whether we're at the edge of an inline, adjacent collapsed whitespace is the same as no sibling at all. |
| if (is<RenderText>(*child) && !downcast<RenderText>(*child).text().length()) |
| return true; |
| #if ENABLE(CSS_BOX_DECORATION_BREAK) |
| if (is<RenderLineBreak>(*child) && child->parent()->style().boxDecorationBreak() == BoxDecorationBreak::Clone) |
| return true; |
| #endif |
| return false; |
| } |
| |
| inline RenderObject* previousInFlowSibling(RenderObject* child) |
| { |
| do { |
| child = child->previousSibling(); |
| } while (child && child->isOutOfFlowPositioned()); |
| return child; |
| } |
| |
| inline LayoutUnit inlineLogicalWidth(RenderObject* child, bool checkStartEdge = true, bool checkEndEdge = true) |
| { |
| unsigned lineDepth = 1; |
| LayoutUnit extraWidth; |
| RenderElement* parent = child->parent(); |
| while (is<RenderInline>(*parent) && lineDepth++ < cMaxLineDepth) { |
| const auto& parentAsRenderInline = downcast<RenderInline>(*parent); |
| if (!isEmptyInline(parentAsRenderInline)) { |
| checkStartEdge = checkStartEdge && shouldAddBorderPaddingMargin(previousInFlowSibling(child)); |
| if (checkStartEdge) |
| extraWidth += borderPaddingMarginStart(parentAsRenderInline); |
| checkEndEdge = checkEndEdge && shouldAddBorderPaddingMargin(child->nextSibling()); |
| if (checkEndEdge) |
| extraWidth += borderPaddingMarginEnd(parentAsRenderInline); |
| if (!checkStartEdge && !checkEndEdge) |
| return extraWidth; |
| } |
| child = parent; |
| parent = child->parent(); |
| } |
| return extraWidth; |
| } |
| |
| inline void BreakingContext::handleOutOfFlowPositioned(Vector<RenderBox*>& positionedObjects) |
| { |
| // If our original display wasn't an inline type, then we can determine our static inline position now. |
| auto& box = downcast<RenderBox>(*m_current.renderer()); |
| bool isInlineType = box.style().isOriginalDisplayInlineType(); |
| if (!isInlineType) |
| m_block.setStaticInlinePositionForChild(box, m_block.logicalHeight(), m_block.startOffsetForContent(m_block.logicalHeight())); |
| else { |
| // If our original display was an DisplayType::Inline type, then we can determine our static y position now. |
| box.layer()->setStaticBlockPosition(m_block.logicalHeight()); |
| } |
| |
| // If we're ignoring spaces, we have to stop and include this object and |
| // then start ignoring spaces again. |
| if (isInlineType || box.container()->isRenderInline()) { |
| if (m_ignoringSpaces) |
| m_lineWhitespaceCollapsingState.ensureLineBoxInsideIgnoredSpaces(box); |
| m_trailingObjects.appendBoxIfNeeded(box); |
| } else |
| positionedObjects.append(&box); |
| |
| m_width.addUncommittedWidth(inlineLogicalWidth(&box)); |
| // Reset prior line break context characters. |
| m_renderTextInfo.lineBreakIterator.resetPriorContext(); |
| } |
| |
| inline void BreakingContext::handleFloat() |
| { |
| auto& floatBox = downcast<RenderBox>(*m_current.renderer()); |
| const auto& floatingObject = *m_lineBreaker.insertFloatingObject(floatBox); |
| // check if it fits in the current line. |
| // If it does, position it now, otherwise, position |
| // it after moving to next line (in clearFloats() func) |
| if (m_floatsFitOnLine && m_width.fitsOnLineExcludingTrailingWhitespace(m_block.logicalWidthForFloat(floatingObject))) { |
| m_lineBreaker.positionNewFloatOnLine(floatingObject, m_lastFloatFromPreviousLine, m_lineInfo, m_width); |
| if (m_lineBreak.renderer() == m_current.renderer()) { |
| ASSERT(!m_lineBreak.offset()); |
| m_lineBreak.increment(); |
| } |
| } else |
| m_floatsFitOnLine = false; |
| // Update prior line break context characters, using U+FFFD (OBJECT REPLACEMENT CHARACTER) for floating element. |
| m_renderTextInfo.lineBreakIterator.updatePriorContext(replacementCharacter); |
| } |
| |
| // This is currently just used for list markers and inline flows that have line boxes. Neither should |
| // have an effect on whitespace at the start of the line. |
| inline bool shouldSkipWhitespaceAfterStartObject(RenderBlockFlow& block, RenderObject* o, LineWhitespaceCollapsingState& lineWhitespaceCollapsingState) |
| { |
| RenderObject* next = bidiNextSkippingEmptyInlines(block, o); |
| while (next && next->isFloatingOrOutOfFlowPositioned()) |
| next = bidiNextSkippingEmptyInlines(block, next); |
| |
| if (is<RenderText>(next) && downcast<RenderText>(*next).text().length() > 0) { |
| RenderText& nextText = downcast<RenderText>(*next); |
| UChar nextChar = nextText.characterAt(0); |
| if (nextText.style().isCollapsibleWhiteSpace(nextChar)) { |
| lineWhitespaceCollapsingState.startIgnoringSpaces(InlineIterator(nullptr, o, 0)); |
| return true; |
| } |
| } |
| |
| return false; |
| } |
| |
| inline void BreakingContext::handleEmptyInline() |
| { |
| RenderInline& flowBox = downcast<RenderInline>(*m_current.renderer()); |
| |
| // This should only end up being called on empty inlines |
| ASSERT(isEmptyInline(flowBox)); |
| |
| // Now that some inline flows have line boxes, if we are already ignoring spaces, we need |
| // to make sure that we stop to include this object and then start ignoring spaces again. |
| // If this object is at the start of the line, we need to behave like list markers and |
| // start ignoring spaces. |
| bool requiresLineBox = alwaysRequiresLineBox(flowBox); |
| if (requiresLineBox || requiresLineBoxForContent(flowBox, m_lineInfo)) { |
| // An empty inline that only has line-height, vertical-align or font-metrics will only get a |
| // line box to affect the height of the line if the rest of the line is not empty. |
| if (requiresLineBox) |
| m_lineInfo.setEmpty(false, &m_block, &m_width); |
| if (m_ignoringSpaces) { |
| m_trailingObjects.clear(); |
| m_lineWhitespaceCollapsingState.ensureLineBoxInsideIgnoredSpaces(*m_current.renderer()); |
| } else if (m_blockStyle.collapseWhiteSpace() && m_resolver.position().renderer() == m_current.renderer() |
| && shouldSkipWhitespaceAfterStartObject(m_block, m_current.renderer(), m_lineWhitespaceCollapsingState)) { |
| // Like with list markers, we start ignoring spaces to make sure that any |
| // additional spaces we see will be discarded. |
| m_currentCharacterIsSpace = true; |
| m_currentCharacterIsWS = true; |
| m_ignoringSpaces = true; |
| } else |
| m_trailingObjects.appendBoxIfNeeded(flowBox); |
| } |
| |
| float inlineWidth = inlineLogicalWidth(m_current.renderer()) + borderPaddingMarginStart(flowBox) + borderPaddingMarginEnd(flowBox); |
| m_width.addUncommittedWidth(inlineWidth); |
| if (m_hangsAtEnd && inlineWidth) |
| m_hangsAtEnd = false; |
| } |
| |
| inline void BreakingContext::handleReplaced() |
| { |
| auto& replacedBox = downcast<RenderBox>(*m_current.renderer()); |
| |
| if (m_atStart) |
| m_width.updateAvailableWidth(replacedBox.logicalHeight()); |
| |
| // Break on replaced elements if either has normal white-space. |
| if ((m_autoWrap || RenderStyle::autoWrap(m_lastWS)) && (!replacedBox.isImage() || m_allowImagesToBreak) |
| && (!is<RenderRubyRun>(replacedBox) || downcast<RenderRubyRun>(replacedBox).canBreakBefore(m_renderTextInfo.lineBreakIterator))) { |
| if (auto* renderer = m_current.renderer()) |
| commitLineBreakAtCurrentWidth(*renderer); |
| else |
| commitLineBreakClear(); |
| } else |
| m_hangsAtEnd = false; |
| |
| if (m_ignoringSpaces) |
| m_lineWhitespaceCollapsingState.stopIgnoringSpaces(InlineIterator(0, &replacedBox, 0)); |
| |
| m_lineInfo.setEmpty(false, &m_block, &m_width); |
| m_ignoringSpaces = false; |
| m_currentCharacterIsSpace = false; |
| m_currentCharacterIsWS = false; |
| m_trailingObjects.clear(); |
| |
| // Optimize for a common case. If we can't find whitespace after the list |
| // item, then this is all moot. |
| LayoutUnit replacedLogicalWidth = m_block.logicalWidthForChild(replacedBox) + m_block.marginStartForChild(replacedBox) + m_block.marginEndForChild(replacedBox) + inlineLogicalWidth(&replacedBox); |
| if (is<RenderListMarker>(replacedBox)) { |
| if (m_blockStyle.collapseWhiteSpace() && shouldSkipWhitespaceAfterStartObject(m_block, &replacedBox, m_lineWhitespaceCollapsingState)) { |
| // Like with inline flows, we start ignoring spaces to make sure that any |
| // additional spaces we see will be discarded. |
| m_currentCharacterIsSpace = true; |
| m_currentCharacterIsWS = false; |
| m_ignoringSpaces = true; |
| } |
| if (downcast<RenderListMarker>(replacedBox).isInside()) |
| m_width.addUncommittedReplacedWidth(replacedLogicalWidth); |
| } else |
| m_width.addUncommittedReplacedWidth(replacedLogicalWidth); |
| if (is<RenderRubyRun>(replacedBox)) { |
| m_width.applyOverhang(downcast<RenderRubyRun>(replacedBox), m_lastObject, m_nextObject); |
| downcast<RenderRubyRun>(replacedBox).updatePriorContextFromCachedBreakIterator(m_renderTextInfo.lineBreakIterator); |
| } else { |
| // Update prior line break context characters, using U+FFFD (OBJECT REPLACEMENT CHARACTER) for replaced element. |
| m_renderTextInfo.lineBreakIterator.updatePriorContext(replacementCharacter); |
| } |
| } |
| |
| inline float firstPositiveWidth(const WordMeasurements& wordMeasurements) |
| { |
| for (size_t i = 0; i < wordMeasurements.size(); ++i) { |
| if (wordMeasurements[i].width > 0) |
| return wordMeasurements[i].width; |
| } |
| return 0; |
| } |
| |
| inline bool iteratorIsBeyondEndOfRenderCombineText(const InlineIterator& iter, RenderCombineText& renderer) |
| { |
| return iter.renderer() == &renderer && iter.offset() >= renderer.text().length(); |
| } |
| |
| inline void nextCharacter(UChar& currentCharacter, UChar& lastCharacter, UChar& secondToLastCharacter) |
| { |
| secondToLastCharacter = lastCharacter; |
| lastCharacter = currentCharacter; |
| } |
| |
| // FIXME: Don't let counters mark themselves as needing pref width recalcs during layout |
| // so we don't need this hack. |
| inline void updateCounterIfNeeded(RenderText& renderText) |
| { |
| if (!renderText.preferredLogicalWidthsDirty() || !is<RenderCounter>(renderText)) |
| return; |
| downcast<RenderCounter>(renderText).updateCounter(); |
| } |
| |
| inline float measureHyphenWidth(RenderText& renderer, const FontCascade& font, HashSet<const Font*>* fallbackFonts = 0) |
| { |
| const RenderStyle& style = renderer.style(); |
| return font.width(RenderBlock::constructTextRun(style.hyphenString().string(), style), fallbackFonts); |
| } |
| |
| ALWAYS_INLINE float textWidth(RenderText& text, unsigned from, unsigned len, const FontCascade& font, float xPos, bool isFixedPitch, bool collapseWhiteSpace, HashSet<const Font*>& fallbackFonts, TextLayout* layout = nullptr) |
| { |
| const RenderStyle& style = text.style(); |
| |
| GlyphOverflow glyphOverflow; |
| // FIXME: This is not the right level of abstraction for isFixedPitch. Font fallback may make it such that the fixed pitch font is never actually used! |
| if (isFixedPitch || (!from && len == text.text().length()) || style.hasTextCombine()) |
| return text.width(from, len, font, xPos, &fallbackFonts, &glyphOverflow); |
| |
| if (layout) |
| return FontCascade::width(*layout, from, len, &fallbackFonts); |
| |
| TextRun run = RenderBlock::constructTextRun(text, from, len, style); |
| run.setCharacterScanForCodePath(!text.canUseSimpleFontCodePath()); |
| run.setTabSize(!collapseWhiteSpace, style.tabSize()); |
| run.setXPos(xPos); |
| return font.width(run, &fallbackFonts, &glyphOverflow); |
| } |
| |
| // Adding a pair of whitespace collapsing transitions before a character will split it out into a new line box. |
| inline void ensureCharacterGetsLineBox(LineWhitespaceCollapsingState& lineWhitespaceCollapsingState, InlineIterator& textParagraphSeparator) |
| { |
| InlineIterator transition(0, textParagraphSeparator.renderer(), textParagraphSeparator.offset()); |
| lineWhitespaceCollapsingState.startIgnoringSpaces(InlineIterator(0, textParagraphSeparator.renderer(), textParagraphSeparator.offset() - 1)); |
| lineWhitespaceCollapsingState.stopIgnoringSpaces(InlineIterator(0, textParagraphSeparator.renderer(), textParagraphSeparator.offset())); |
| } |
| |
| inline void tryHyphenating(RenderText& text, const FontCascade& font, const AtomString& localeIdentifier, unsigned consecutiveHyphenatedLines, int consecutiveHyphenatedLinesLimit, int minimumPrefixLimit, int minimumSuffixLimit, unsigned lastSpace, unsigned pos, float xPos, float availableWidth, bool isFixedPitch, bool collapseWhiteSpace, int lastSpaceWordSpacing, InlineIterator& lineBreak, Optional<unsigned> nextBreakable, bool& hyphenated) |
| { |
| // Map 'hyphenate-limit-{before,after}: auto;' to 2. |
| unsigned minimumPrefixLength; |
| unsigned minimumSuffixLength; |
| |
| if (minimumPrefixLimit < 0) |
| minimumPrefixLength = 2; |
| else |
| minimumPrefixLength = static_cast<unsigned>(minimumPrefixLimit); |
| |
| if (minimumSuffixLimit < 0) |
| minimumSuffixLength = 2; |
| else |
| minimumSuffixLength = static_cast<unsigned>(minimumSuffixLimit); |
| |
| if (pos - lastSpace <= minimumSuffixLength) |
| return; |
| |
| if (consecutiveHyphenatedLinesLimit >= 0 && consecutiveHyphenatedLines >= static_cast<unsigned>(consecutiveHyphenatedLinesLimit)) |
| return; |
| |
| float hyphenWidth = measureHyphenWidth(text, font); |
| |
| float maxPrefixWidth = availableWidth - xPos - hyphenWidth - lastSpaceWordSpacing; |
| if (!enoughWidthForHyphenation(maxPrefixWidth, font.pixelSize())) |
| return; |
| |
| const RenderStyle& style = text.style(); |
| TextRun run = RenderBlock::constructTextRun(text, lastSpace, pos - lastSpace, style); |
| run.setTabSize(!collapseWhiteSpace, style.tabSize()); |
| run.setXPos(xPos + lastSpaceWordSpacing); |
| |
| unsigned prefixLength = font.offsetForPosition(run, maxPrefixWidth, false); |
| if (prefixLength < minimumPrefixLength) |
| return; |
| |
| prefixLength = lastHyphenLocation(StringView(text.text()).substring(lastSpace, pos - lastSpace), std::min(prefixLength, pos - lastSpace - minimumSuffixLength) + 1, localeIdentifier); |
| if (!prefixLength || prefixLength < minimumPrefixLength) |
| return; |
| |
| // When lastSpace is a space, which it always is except sometimes at the beginning of a line or after collapsed |
| // space, it should not count towards hyphenate-limit-before. |
| if (prefixLength == minimumPrefixLength) { |
| UChar characterAtLastSpace = text.characterAt(lastSpace); |
| if (characterAtLastSpace == ' ' || characterAtLastSpace == '\n' || characterAtLastSpace == '\t' || characterAtLastSpace == noBreakSpace) |
| return; |
| } |
| |
| ASSERT(pos - lastSpace - prefixLength >= minimumSuffixLength); |
| |
| #if ASSERT_ENABLED |
| HashSet<const Font*> fallbackFonts; |
| float prefixWidth = hyphenWidth + textWidth(text, lastSpace, prefixLength, font, xPos, isFixedPitch, collapseWhiteSpace, fallbackFonts) + lastSpaceWordSpacing; |
| ASSERT(xPos + prefixWidth <= availableWidth); |
| #else |
| UNUSED_PARAM(isFixedPitch); |
| #endif |
| |
| lineBreak.moveTo(text, lastSpace + prefixLength, nextBreakable); |
| hyphenated = true; |
| } |
| |
| inline float BreakingContext::computeAdditionalBetweenWordsWidth(RenderText& renderText, TextLayout* textLayout, UChar currentCharacter, WordTrailingSpace& wordTrailingSpace, HashSet<const Font*>& fallbackFonts, WordMeasurements& wordMeasurements, const FontCascade& font, bool isFixedPitch, unsigned lastSpace, float lastSpaceWordSpacing, float wordSpacingForWordMeasurement, unsigned offset) |
| { |
| wordMeasurements.grow(wordMeasurements.size() + 1); |
| WordMeasurement& wordMeasurement = wordMeasurements.last(); |
| |
| wordMeasurement.renderer = &renderText; |
| wordMeasurement.endOffset = offset; |
| wordMeasurement.startOffset = lastSpace; |
| |
| float additionalTempWidth = 0; |
| Optional<float> wordTrailingSpaceWidth; |
| if (currentCharacter == ' ') |
| wordTrailingSpaceWidth = wordTrailingSpace.width(fallbackFonts); |
| if (wordTrailingSpaceWidth) |
| additionalTempWidth = textWidth(renderText, lastSpace, offset + 1 - lastSpace, font, m_width.currentWidth(), isFixedPitch, m_collapseWhiteSpace, wordMeasurement.fallbackFonts, textLayout) - wordTrailingSpaceWidth.value(); |
| else |
| additionalTempWidth = textWidth(renderText, lastSpace, offset - lastSpace, font, m_width.currentWidth(), isFixedPitch, m_collapseWhiteSpace, wordMeasurement.fallbackFonts, textLayout); |
| |
| if (wordMeasurement.fallbackFonts.isEmpty() && !fallbackFonts.isEmpty()) |
| wordMeasurement.fallbackFonts.swap(fallbackFonts); |
| fallbackFonts.clear(); |
| |
| wordMeasurement.width = additionalTempWidth + wordSpacingForWordMeasurement; |
| additionalTempWidth += lastSpaceWordSpacing; |
| return additionalTempWidth; |
| } |
| |
| inline bool BreakingContext::handleText(WordMeasurements& wordMeasurements, bool& hyphenated, unsigned& consecutiveHyphenatedLines) |
| { |
| if (!m_current.offset()) |
| m_appliedStartWidth = false; |
| |
| RenderObject& renderObject = *m_current.renderer(); |
| RenderText& renderText = downcast<RenderText>(renderObject); |
| |
| bool isSVGText = renderText.isSVGInlineText(); |
| |
| // If we have left a no-wrap inline and entered an autowrap inline while ignoring spaces |
| // then we need to mark the start of the autowrap inline as a potential linebreak now. |
| if (m_autoWrap && !RenderStyle::autoWrap(m_lastWS) && m_ignoringSpaces) |
| commitLineBreakAtCurrentWidth(renderText); |
| |
| if (renderText.style().hasTextCombine() && is<RenderCombineText>(*m_current.renderer())) { |
| auto& combineRenderer = downcast<RenderCombineText>(*m_current.renderer()); |
| combineRenderer.combineTextIfNeeded(); |
| // The length of the renderer's text may have changed. Increment stale iterator positions |
| if (iteratorIsBeyondEndOfRenderCombineText(m_lineBreak, combineRenderer)) { |
| ASSERT(iteratorIsBeyondEndOfRenderCombineText(m_resolver.position(), combineRenderer)); |
| m_lineBreak.increment(); |
| m_resolver.increment(); |
| } |
| } |
| |
| const RenderStyle& style = lineStyle(renderText, m_lineInfo); |
| const FontCascade& font = style.fontCascade(); |
| bool isFixedPitch = font.isFixedPitch(); |
| bool canHyphenate = style.hyphens() == Hyphens::Auto && WebCore::canHyphenate(style.locale()); |
| bool canHangPunctuationAtStart = style.hangingPunctuation().contains(HangingPunctuation::First); |
| bool canHangPunctuationAtEnd = style.hangingPunctuation().contains(HangingPunctuation::Last); |
| bool canHangStopOrCommaAtLineEnd = style.hangingPunctuation().contains(HangingPunctuation::AllowEnd); |
| int endPunctuationIndex = canHangPunctuationAtEnd && m_collapseWhiteSpace ? renderText.lastCharacterIndexStrippingSpaces() : renderText.text().length() - 1; |
| unsigned lastSpace = m_current.offset(); |
| float wordSpacing = m_currentStyle->fontCascade().wordSpacing(); |
| float lastSpaceWordSpacing = 0; |
| float wordSpacingForWordMeasurement = 0; |
| |
| float wrapWidthOffset = m_width.uncommittedWidth() + inlineLogicalWidth(m_current.renderer(), !m_appliedStartWidth, true); |
| float wrapW = wrapWidthOffset; |
| float charWidth = 0; |
| bool breakNBSP = m_autoWrap && m_currentStyle->nbspMode() == NBSPMode::Space; |
| // Auto-wrapping text should wrap in the middle of a word only if it could not wrap before the word, |
| // which is only possible if the word is the first thing on the line. |
| bool breakWords = m_currentStyle->breakWords() && ((m_autoWrap && (!m_width.committedWidth() && !m_width.hasCommittedReplaced())) || m_currWS == WhiteSpace::Pre); |
| bool midWordBreak = false; |
| bool breakAnywhere = m_currentStyle->lineBreak() == LineBreak::Anywhere && m_autoWrap; |
| bool breakAll = (m_currentStyle->wordBreak() == WordBreak::BreakAll || breakAnywhere) && m_autoWrap; |
| bool keepAllWords = m_currentStyle->wordBreak() == WordBreak::KeepAll; |
| float hyphenWidth = 0; |
| auto iteratorMode = mapLineBreakToIteratorMode(m_blockStyle.lineBreak()); |
| bool canUseLineBreakShortcut = iteratorMode == LineBreakIteratorMode::Default; |
| bool isLineEmpty = m_lineInfo.isEmpty(); |
| |
| if (isSVGText) { |
| breakWords = false; |
| breakAll = false; |
| } |
| |
| if (m_renderTextInfo.text != &renderText) { |
| updateCounterIfNeeded(renderText); |
| m_renderTextInfo.text = &renderText; |
| m_renderTextInfo.font = &font; |
| m_renderTextInfo.layout = font.createLayout(renderText, m_width.currentWidth(), m_collapseWhiteSpace); |
| m_renderTextInfo.lineBreakIterator.resetStringAndReleaseIterator(renderText.text(), style.locale(), iteratorMode); |
| } else if (m_renderTextInfo.layout && m_renderTextInfo.font != &font) { |
| m_renderTextInfo.font = &font; |
| m_renderTextInfo.layout = font.createLayout(renderText, m_width.currentWidth(), m_collapseWhiteSpace); |
| } |
| |
| HashSet<const Font*> fallbackFonts; |
| m_hasFormerOpportunity = false; |
| bool canBreakMidWord = breakWords || breakAll; |
| UChar lastCharacterFromPreviousRenderText = m_renderTextInfo.lineBreakIterator.lastCharacter(); |
| UChar lastCharacter = m_renderTextInfo.lineBreakIterator.lastCharacter(); |
| UChar secondToLastCharacter = m_renderTextInfo.lineBreakIterator.secondToLastCharacter(); |
| // Non-zero only when kerning is enabled and TextLayout isn't used, in which case we measure |
| // words with their trailing space, then subtract its width. |
| TextLayout* textLayout = m_renderTextInfo.layout.get(); |
| WordTrailingSpace wordTrailingSpace(style, !textLayout); |
| for (; m_current.offset() < renderText.text().length(); m_current.fastIncrementInTextNode()) { |
| bool previousCharacterIsSpace = m_currentCharacterIsSpace; |
| bool previousCharacterIsWS = m_currentCharacterIsWS; |
| UChar c = m_current.current(); |
| m_currentCharacterIsSpace = c == ' ' || c == '\t' || (!m_preservesNewline && (c == '\n')); |
| |
| // A single preserved leading white-space doesn't fulfill the 'betweenWords' condition, however it's indeed a |
| // soft-breaking opportunty so we may want to avoid breaking in the middle of the word. |
| if (m_atStart && m_currentCharacterIsSpace && !previousCharacterIsSpace) { |
| m_hasFormerOpportunity = !breakAnywhere; |
| breakWords = false; |
| canBreakMidWord = breakAll; |
| } |
| |
| if (canHangPunctuationAtStart && m_width.isFirstLine() && !m_width.committedWidth() && !wrapW && !inlineLogicalWidth(m_current.renderer(), true, false)) { |
| m_width.addUncommittedWidth(-renderText.hangablePunctuationStartWidth(m_current.offset())); |
| canHangPunctuationAtStart = false; |
| } |
| |
| if (canHangPunctuationAtEnd && !m_nextObject && (int)m_current.offset() == endPunctuationIndex && !inlineLogicalWidth(m_current.renderer(), false, true)) { |
| m_width.addUncommittedWidth(-renderText.hangablePunctuationEndWidth(endPunctuationIndex)); |
| canHangPunctuationAtEnd = false; |
| } |
| |
| if (!m_collapseWhiteSpace || !m_currentCharacterIsSpace) |
| m_lineInfo.setEmpty(false, &m_block, &m_width); |
| |
| if (c == softHyphen && m_autoWrap && !hyphenWidth && style.hyphens() != Hyphens::None) { |
| hyphenWidth = measureHyphenWidth(renderText, font, &fallbackFonts); |
| m_width.addUncommittedWidth(hyphenWidth); |
| } |
| |
| bool applyWordSpacing = false; |
| |
| m_currentCharacterIsWS = m_currentCharacterIsSpace || (breakNBSP && c == noBreakSpace); |
| |
| if (canBreakMidWord && !midWordBreak && (!m_currentCharacterIsSpace || m_atStart || style.whiteSpace() != WhiteSpace::PreWrap)) { |
| wrapW += charWidth; |
| bool midWordBreakIsBeforeSurrogatePair = U16_IS_LEAD(c) && U16_IS_TRAIL(renderText.characterAt(m_current.offset() + 1)); |
| charWidth = textWidth(renderText, m_current.offset(), midWordBreakIsBeforeSurrogatePair ? 2 : 1, font, m_width.committedWidth() + wrapW, isFixedPitch, m_collapseWhiteSpace, fallbackFonts, textLayout); |
| midWordBreak = m_width.committedWidth() + wrapW + charWidth > m_width.availableWidth(); |
| } |
| |
| Optional<unsigned> nextBreakablePosition = m_current.nextBreakablePosition(); |
| bool betweenWords = c == '\n' || (m_currWS != WhiteSpace::Pre && !m_atStart && isBreakable(m_renderTextInfo.lineBreakIterator, m_current.offset(), nextBreakablePosition, breakNBSP, canUseLineBreakShortcut, keepAllWords, breakAnywhere) |
| && (style.hyphens() != Hyphens::None || (m_current.previousInSameNode() != softHyphen))); |
| m_current.setNextBreakablePosition(nextBreakablePosition); |
| |
| if (canHangStopOrCommaAtLineEnd && renderText.isHangableStopOrComma(c) && m_width.fitsOnLine()) { |
| // We need to see if a measurement that excludes the stop would fit. If so, then we should hang |
| // the stop/comma at the end. First measure including the comma. |
| m_hangsAtEnd = false; |
| float inlineStartWidth = !m_appliedStartWidth ? inlineLogicalWidth(m_current.renderer(), true, false) : 0_lu; |
| float widthIncludingComma = computeAdditionalBetweenWordsWidth(renderText, textLayout, c, wordTrailingSpace, fallbackFonts, wordMeasurements, font, isFixedPitch, lastSpace, lastSpaceWordSpacing, wordSpacingForWordMeasurement, m_current.offset() + 1) + inlineStartWidth; |
| m_width.addUncommittedWidth(widthIncludingComma); |
| if (!m_width.fitsOnLine()) { |
| // See if we fit without the comma involved. If we do, then this is a potential hang point. |
| float widthWithoutStopOrComma = computeAdditionalBetweenWordsWidth(renderText, textLayout, lastCharacter, wordTrailingSpace, fallbackFonts, wordMeasurements, font, isFixedPitch, lastSpace, lastSpaceWordSpacing, wordSpacingForWordMeasurement, m_current.offset()) + inlineStartWidth; |
| m_width.addUncommittedWidth(widthWithoutStopOrComma - widthIncludingComma); |
| if (m_width.fitsOnLine()) |
| m_hangsAtEnd = true; |
| } else |
| m_width.addUncommittedWidth(-widthIncludingComma); |
| } |
| |
| if (betweenWords || midWordBreak) { |
| bool stoppedIgnoringSpaces = false; |
| if (m_ignoringSpaces) { |
| lastSpaceWordSpacing = 0; |
| if (!m_currentCharacterIsSpace) { |
| // Stop ignoring spaces and begin at this new point. |
| m_ignoringSpaces = false; |
| wordSpacingForWordMeasurement = 0; |
| lastSpace = m_current.offset(); // e.g., "Foo goo", don't add in any of the ignored spaces. |
| m_lineWhitespaceCollapsingState.stopIgnoringSpaces(InlineIterator(0, m_current.renderer(), m_current.offset())); |
| stoppedIgnoringSpaces = true; |
| } else { |
| // Just keep ignoring these spaces. |
| nextCharacter(c, lastCharacter, secondToLastCharacter); |
| continue; |
| } |
| } |
| |
| float additionalTempWidth = computeAdditionalBetweenWordsWidth(renderText, textLayout, c, wordTrailingSpace, fallbackFonts, wordMeasurements, font, isFixedPitch, lastSpace, lastSpaceWordSpacing, wordSpacingForWordMeasurement, m_current.offset()); |
| m_width.addUncommittedWidth(additionalTempWidth); |
| |
| WordMeasurement& wordMeasurement = wordMeasurements.last(); |
| |
| if (m_collapseWhiteSpace && previousCharacterIsSpace && m_currentCharacterIsSpace && additionalTempWidth) |
| m_width.setTrailingWhitespaceWidth(additionalTempWidth); |
| |
| if (!m_appliedStartWidth) { |
| float inlineStartWidth = inlineLogicalWidth(m_current.renderer(), true, false); |
| m_width.addUncommittedWidth(inlineStartWidth); |
| m_appliedStartWidth = true; |
| if (m_hangsAtEnd && inlineStartWidth) |
| m_hangsAtEnd = false; |
| } |
| |
| applyWordSpacing = wordSpacing && m_currentCharacterIsSpace; |
| |
| if (!m_width.hasCommitted() && m_autoWrap && !fitsOnLineOrHangsAtEnd()) |
| m_width.fitBelowFloats(m_lineInfo.isFirstLine()); |
| |
| if (m_autoWrap || breakWords) { |
| // If we break only after white-space, consider the current character |
| // as candidate width for this line. |
| bool lineWasTooWide = false; |
| if (fitsOnLineOrHangsAtEnd() && m_currentCharacterIsWS && m_currentStyle->breakOnlyAfterWhiteSpace() && (!midWordBreak || m_currWS == WhiteSpace::BreakSpaces)) { |
| float charWidth = textWidth(renderText, m_current.offset(), 1, font, m_width.currentWidth(), isFixedPitch, m_collapseWhiteSpace, wordMeasurement.fallbackFonts, textLayout) + (applyWordSpacing ? wordSpacing : 0); |
| // Check if line is too big even without the extra space |
| // at the end of the line. If it is not, do nothing. |
| // If the line needs the extra whitespace to be too long, |
| // then move the line break to the space and skip all |
| // additional whitespace. |
| if (!m_width.fitsOnLineIncludingExtraWidth(charWidth)) { |
| lineWasTooWide = true; |
| if (m_currWS == WhiteSpace::BreakSpaces) |
| trailingSpacesHang(m_lineBreak, renderObject, canBreakMidWord, previousCharacterIsSpace); |
| else { |
| m_lineBreak.moveTo(renderObject, m_current.offset(), m_current.nextBreakablePosition()); |
| m_lineBreaker.skipTrailingWhitespace(m_lineBreak, m_lineInfo); |
| } |
| } |
| } |
| if ((lineWasTooWide || !m_width.fitsOnLine()) && !m_hangsAtEnd) { |
| // Don't try to hyphenate at the final break of a block, since this means there is |
| // no more content, and a hyphenated single word would end up on a line by itself. This looks |
| // bad so just don't allow it. |
| if (canHyphenate && !m_width.fitsOnLine() && (m_nextObject || !renderText.containsOnlyHTMLWhitespace(m_current.offset(), renderText.text().length() - m_current.offset()) || isLineEmpty)) { |
| tryHyphenating(renderText, font, style.locale(), consecutiveHyphenatedLines, m_blockStyle.hyphenationLimitLines(), style.hyphenationLimitBefore(), style.hyphenationLimitAfter(), lastSpace, m_current.offset(), m_width.currentWidth() - additionalTempWidth, m_width.availableWidth(), isFixedPitch, m_collapseWhiteSpace, lastSpaceWordSpacing, m_lineBreak, m_current.nextBreakablePosition(), m_lineBreaker.m_hyphenated); |
| if (m_lineBreaker.m_hyphenated) { |
| m_atEnd = true; |
| return false; |
| } |
| } |
| if (m_lineBreak.atTextParagraphSeparator()) { |
| if (!stoppedIgnoringSpaces && m_current.offset() > 0) |
| ensureCharacterGetsLineBox(m_lineWhitespaceCollapsingState, m_current); |
| m_lineBreak.increment(); |
| m_lineInfo.setPreviousLineBrokeCleanly(true); |
| wordMeasurement.endOffset = m_lineBreak.offset(); |
| } |
| // Check if the last breaking position is a soft-hyphen. |
| if (!hyphenated && style.hyphens() != Hyphens::None) { |
| Optional<unsigned> lastBreakingPositon; |
| const RenderObject* rendererAtBreakingPosition = nullptr; |
| if (m_lineBreak.offset() || m_lineBreak.nextBreakablePosition()) { |
| lastBreakingPositon = m_lineBreak.offset(); |
| rendererAtBreakingPosition = m_lineBreak.renderer(); |
| } else if (m_current.nextBreakablePosition() && m_current.nextBreakablePosition().value() <= m_current.offset()) { |
| // We might just be right after the soft-hyphen |
| lastBreakingPositon = m_current.nextBreakablePosition().value(); |
| rendererAtBreakingPosition = m_current.renderer(); |
| } |
| if (lastBreakingPositon) { |
| Optional<UChar> characterBeforeBreakingPosition; |
| // When last breaking position points to the start of the current context, we need to look at the last character from |
| // the previous non-empty text renderer. |
| if (!lastBreakingPositon.value()) |
| characterBeforeBreakingPosition = lastCharacterFromPreviousRenderText; |
| else if (is<RenderText>(rendererAtBreakingPosition)) { |
| const auto& textRenderer = downcast<RenderText>(*rendererAtBreakingPosition); |
| ASSERT(lastBreakingPositon.value() >= 1 && textRenderer.text().length() > (lastBreakingPositon.value() - 1)); |
| characterBeforeBreakingPosition = textRenderer.characterAt(lastBreakingPositon.value() - 1); |
| } |
| if (characterBeforeBreakingPosition) |
| hyphenated = characterBeforeBreakingPosition.value() == softHyphen; |
| } |
| } |
| if (m_lineBreak.offset() && m_lineBreak.offset() != (unsigned)wordMeasurement.endOffset && !wordMeasurement.width) { |
| if (charWidth) { |
| wordMeasurement.endOffset = m_lineBreak.offset(); |
| wordMeasurement.width = charWidth; |
| } |
| } |
| // Didn't fit. Jump to the end unless there's still an opportunity to collapse whitespace. |
| if (m_ignoringSpaces || !m_collapseWhiteSpace || !m_currentCharacterIsSpace || !previousCharacterIsSpace) { |
| m_atEnd = true; |
| return false; |
| } |
| } else { |
| if (!betweenWords || (midWordBreak && !m_autoWrap)) |
| m_width.addUncommittedWidth(-additionalTempWidth); |
| if (hyphenWidth) { |
| // Subtract the width of the soft hyphen out since we fit on a line. |
| m_width.addUncommittedWidth(-hyphenWidth); |
| hyphenWidth = 0; |
| } |
| } |
| } |
| |
| if (c == '\n' && m_preservesNewline) { |
| if (!stoppedIgnoringSpaces && m_current.offset()) |
| ensureCharacterGetsLineBox(m_lineWhitespaceCollapsingState, m_current); |
| commitLineBreakAtCurrentWidth(renderObject, m_current.offset(), m_current.nextBreakablePosition()); |
| m_lineBreak.increment(); |
| m_lineInfo.setPreviousLineBrokeCleanly(true); |
| return true; |
| } |
| |
| if (m_autoWrap && betweenWords) { |
| commitLineBreakAtCurrentWidth(renderObject, m_current.offset(), m_current.nextBreakablePosition()); |
| wrapWidthOffset = 0; |
| wrapW = wrapWidthOffset; |
| // Auto-wrapping text should not wrap in the middle of a word once it has had an |
| // opportunity to break after a word. |
| m_hasFormerOpportunity = !breakAnywhere; |
| breakWords = false; |
| canBreakMidWord = breakAll; |
| } |
| |
| if (midWordBreak && !U16_IS_TRAIL(c) && !(U_GET_GC_MASK(c) & U_GC_M_MASK)) { |
| // Remember this as a breakable position in case |
| // adding the end width forces a break. |
| m_lineBreak.moveTo(renderObject, m_current.offset(), m_current.nextBreakablePosition()); |
| midWordBreak &= canBreakMidWord; |
| } |
| |
| if (betweenWords) { |
| lastSpaceWordSpacing = applyWordSpacing ? wordSpacing : 0; |
| wordSpacingForWordMeasurement = (applyWordSpacing && wordMeasurement.width) ? wordSpacing : 0; |
| lastSpace = m_current.offset(); |
| } |
| |
| if (!m_ignoringSpaces && m_currentStyle->collapseWhiteSpace()) { |
| // If we encounter a newline, or if we encounter a second space, |
| // we need to break up this run and enter a mode where we start collapsing spaces. |
| if (m_currentCharacterIsSpace && previousCharacterIsSpace) { |
| m_ignoringSpaces = true; |
| |
| // We just entered a mode where we are ignoring |
| // spaces. Create a transition to terminate the run |
| // before the second space. |
| m_lineWhitespaceCollapsingState.startIgnoringSpaces(m_startOfIgnoredSpaces); |
| m_trailingObjects.updateWhitespaceCollapsingTransitionsForTrailingBoxes(m_lineWhitespaceCollapsingState, InlineIterator(), TrailingObjects::DoNotCollapseFirstSpace); |
| } |
| } |
| // Measuring the width of complex text character-by-character, rather than measuring it all together, |
| // could produce considerably different width values. |
| if (!renderText.canUseSimpleFontCodePath() && midWordBreak && m_width.fitsOnLine()) { |
| midWordBreak = false; |
| wrapW = wrapWidthOffset + additionalTempWidth; |
| } |
| isLineEmpty = m_lineInfo.isEmpty(); |
| } else { |
| if (m_ignoringSpaces) { |
| // Stop ignoring spaces and begin at this new point. |
| m_ignoringSpaces = false; |
| lastSpaceWordSpacing = applyWordSpacing ? wordSpacing : 0; |
| wordSpacingForWordMeasurement = (applyWordSpacing && wordMeasurements.last().width) ? wordSpacing : 0; |
| lastSpace = m_current.offset(); // e.g., "Foo goo", don't add in any of the ignored spaces. |
| m_lineWhitespaceCollapsingState.stopIgnoringSpaces(InlineIterator(nullptr, m_current.renderer(), m_current.offset())); |
| } |
| if (m_hangsAtEnd && !renderText.isHangableStopOrComma(c)) |
| m_hangsAtEnd = false; |
| } |
| |
| if (isSVGText && m_current.offset()) { |
| // Force creation of new InlineBoxes for each absolute positioned character (those that start new text chunks). |
| if (downcast<RenderSVGInlineText>(renderText).characterStartsNewTextChunk(m_current.offset())) |
| ensureCharacterGetsLineBox(m_lineWhitespaceCollapsingState, m_current); |
| } |
| |
| if (m_currentCharacterIsSpace && !previousCharacterIsSpace) { |
| m_startOfIgnoredSpaces.setRenderer(m_current.renderer()); |
| m_startOfIgnoredSpaces.setOffset(m_current.offset()); |
| // Spaces after right-aligned text and before a line-break get collapsed away completely so that the trailing |
| // space doesn't seem to push the text out from the right-hand edge. |
| // FIXME: Do this regardless of the container's alignment - will require rebaselining a lot of test results. |
| if (m_nextObject && m_startOfIgnoredSpaces.offset() && m_nextObject->isBR() && (m_blockStyle.textAlign() == TextAlignMode::Right || m_blockStyle.textAlign() == TextAlignMode::WebKitRight)) { |
| m_startOfIgnoredSpaces.setOffset(m_startOfIgnoredSpaces.offset() - 1); |
| // If there's just a single trailing space start ignoring it now so it collapses away. |
| if (m_current.offset() == renderText.text().length() - 1) |
| m_lineWhitespaceCollapsingState.startIgnoringSpaces(m_startOfIgnoredSpaces); |
| } |
| } |
| |
| if (!m_currentCharacterIsWS && previousCharacterIsWS) { |
| if (m_autoWrap && m_currentStyle->breakOnlyAfterWhiteSpace()) |
| m_lineBreak.moveTo(renderObject, m_current.offset(), m_current.nextBreakablePosition()); |
| } |
| |
| if (m_collapseWhiteSpace && m_currentCharacterIsSpace && !m_ignoringSpaces) |
| m_trailingObjects.setTrailingWhitespace(downcast<RenderText>(m_current.renderer())); |
| else if (!m_currentStyle->collapseWhiteSpace() || !m_currentCharacterIsSpace) |
| m_trailingObjects.clear(); |
| |
| m_atStart = false; |
| nextCharacter(c, lastCharacter, secondToLastCharacter); |
| } |
| |
| m_renderTextInfo.lineBreakIterator.setPriorContext(lastCharacter, secondToLastCharacter); |
| |
| wordMeasurements.grow(wordMeasurements.size() + 1); |
| WordMeasurement& wordMeasurement = wordMeasurements.last(); |
| wordMeasurement.renderer = &renderText; |
| |
| // IMPORTANT: current.m_pos is > length here! |
| float additionalTempWidth = m_ignoringSpaces ? 0 : textWidth(renderText, lastSpace, m_current.offset() - lastSpace, font, m_width.currentWidth(), isFixedPitch, m_collapseWhiteSpace, wordMeasurement.fallbackFonts, textLayout); |
| wordMeasurement.startOffset = lastSpace; |
| wordMeasurement.endOffset = m_current.offset(); |
| wordMeasurement.width = m_ignoringSpaces ? 0 : additionalTempWidth + wordSpacingForWordMeasurement; |
| additionalTempWidth += lastSpaceWordSpacing; |
| |
| float inlineLogicalTempWidth = inlineLogicalWidth(m_current.renderer(), !m_appliedStartWidth, m_includeEndWidth); |
| m_width.addUncommittedWidth(additionalTempWidth + inlineLogicalTempWidth); |
| if (m_hangsAtEnd && inlineLogicalTempWidth) |
| m_hangsAtEnd = false; |
| |
| if (wordMeasurement.fallbackFonts.isEmpty() && !fallbackFonts.isEmpty()) |
| wordMeasurement.fallbackFonts.swap(fallbackFonts); |
| fallbackFonts.clear(); |
| |
| if (m_collapseWhiteSpace && m_currentCharacterIsSpace && additionalTempWidth) |
| m_width.setTrailingWhitespaceWidth(additionalTempWidth, inlineLogicalTempWidth); |
| |
| m_includeEndWidth = false; |
| |
| if (!fitsOnLineOrHangsAtEnd()) { |
| // Don't try to hyphenate at the final break of a block, since this means there is |
| // no more content, and a hyphenated single word would end up on a line by itself. This looks |
| // bad so just don't allow it. |
| if (canHyphenate && (m_nextObject || isLineEmpty)) |
| tryHyphenating(renderText, font, style.locale(), consecutiveHyphenatedLines, m_blockStyle.hyphenationLimitLines(), style.hyphenationLimitBefore(), style.hyphenationLimitAfter(), lastSpace, m_current.offset(), m_width.currentWidth() - additionalTempWidth, m_width.availableWidth(), isFixedPitch, m_collapseWhiteSpace, lastSpaceWordSpacing, m_lineBreak, m_current.nextBreakablePosition(), m_lineBreaker.m_hyphenated); |
| |
| if (!hyphenated && m_lineBreak.previousInSameNode() == softHyphen && style.hyphens() != Hyphens::None) { |
| hyphenated = true; |
| m_atEnd = true; |
| } |
| } |
| return false; |
| } |
| |
| inline bool textBeginsWithBreakablePosition(RenderText& nextText) |
| { |
| UChar c = nextText.characterAt(0); |
| return c == ' ' || c == '\t' || (c == '\n' && !nextText.preservesNewline()); |
| } |
| |
| inline void BreakingContext::trailingSpacesHang(InlineIterator& lineBreak, RenderObject& renderObject, bool canBreakMidWord, bool previousCharacterIsSpace) |
| { |
| ASSERT(m_currWS == WhiteSpace::BreakSpaces); |
| // Avoid breaking before the first white-space after a word if there is a |
| // breaking opportunity before. |
| if (m_hasFormerOpportunity && !previousCharacterIsSpace) |
| return; |
| |
| lineBreak.moveTo(renderObject, m_current.offset(), m_current.nextBreakablePosition()); |
| |
| // Avoid breaking before the first white-space after a word, unless |
| // overflow-wrap or word-break allow to. |
| if (!previousCharacterIsSpace && !canBreakMidWord) |
| lineBreak.increment(); |
| } |
| |
| inline bool BreakingContext::canBreakAtThisPosition() |
| { |
| // If we are no-wrap and have found a line-breaking opportunity already then we should take it. |
| if (m_width.committedWidth() && !m_width.fitsOnLine(m_currentCharacterIsSpace) && m_currWS == WhiteSpace::NoWrap) |
| return true; |
| |
| // Avoid breaking on empty inlines. |
| if (is<RenderInline>(*m_current.renderer()) && isEmptyInline(downcast<RenderInline>(*m_current.renderer()))) |
| return false; |
| |
| // Avoid breaking before empty inlines (as long as the current object isn't replaced). |
| if (!m_current.renderer()->isReplaced() && is<RenderInline>(m_nextObject) && isEmptyInline(downcast<RenderInline>(*m_nextObject))) |
| return false; |
| |
| // Return early if we autowrap and the current character is a space as we will always want to break at such a position. |
| if (m_autoWrap && m_currentCharacterIsSpace) |
| return true; |
| |
| if (m_nextObject && m_nextObject->isLineBreakOpportunity()) |
| return m_autoWrap; |
| |
| bool nextIsAutoWrappingText = is<RenderText>(m_nextObject) && (m_autoWrap || m_nextObject->style().autoWrap()); |
| if (!nextIsAutoWrappingText) |
| return m_autoWrap; |
| RenderText& nextRenderText = downcast<RenderText>(*m_nextObject); |
| bool currentIsTextOrEmptyInline = is<RenderText>(*m_current.renderer()) || (is<RenderInline>(*m_current.renderer()) && isEmptyInline(downcast<RenderInline>(*m_current.renderer()))); |
| if (!currentIsTextOrEmptyInline) |
| return m_autoWrap && !m_current.renderer()->isRubyRun(); |
| |
| bool canBreakHere = !m_currentCharacterIsSpace && textBeginsWithBreakablePosition(nextRenderText); |
| |
| // See if attempting to fit below floats creates more available width on the line. |
| if (!m_width.fitsOnLine() && !m_width.hasCommitted()) |
| m_width.fitBelowFloats(m_lineInfo.isFirstLine()); |
| |
| bool canPlaceOnLine = m_width.fitsOnLine() || !m_autoWrapWasEverTrueOnLine; |
| |
| if (canPlaceOnLine && canBreakHere) |
| commitLineBreakAtCurrentWidth(nextRenderText); |
| |
| return canBreakHere; |
| } |
| |
| inline void BreakingContext::commitAndUpdateLineBreakIfNeeded() |
| { |
| bool checkForBreak = canBreakAtThisPosition(); |
| |
| if (checkForBreak && !m_width.fitsOnLine(m_ignoringSpaces) && !m_hangsAtEnd) { |
| // if we have floats, try to get below them. |
| if (m_currentCharacterIsSpace && !m_ignoringSpaces && m_currentStyle->collapseWhiteSpace()) |
| m_trailingObjects.clear(); |
| |
| if (m_width.committedWidth()) { |
| m_atEnd = true; |
| return; |
| } |
| |
| if (!m_hangsAtEnd) |
| m_width.fitBelowFloats(m_lineInfo.isFirstLine()); |
| |
| // |width| may have been adjusted because we got shoved down past a float (thus |
| // giving us more room), so we need to retest, and only jump to |
| // the end label if we still don't fit on the line. -dwh |
| if (!m_width.fitsOnLine(m_ignoringSpaces)) { |
| m_atEnd = true; |
| return; |
| } |
| } else if (m_blockStyle.autoWrap() && !m_width.fitsOnLine() && !m_width.hasCommitted() && !m_hangsAtEnd) { |
| // If the container autowraps but the current child does not then we still need to ensure that it |
| // wraps and moves below any floats. |
| m_width.fitBelowFloats(m_lineInfo.isFirstLine()); |
| } |
| |
| if (!m_current.renderer()->isFloatingOrOutOfFlowPositioned()) { |
| m_lastObject = m_current.renderer(); |
| if (m_lastObject->isReplaced() && m_autoWrap && !m_lastObject->isRubyRun() && (!m_lastObject->isImage() || m_allowImagesToBreak) && (!is<RenderListMarker>(*m_lastObject) || downcast<RenderListMarker>(*m_lastObject).isInside())) { |
| if (m_nextObject) |
| commitLineBreakAtCurrentWidth(*m_nextObject); |
| else |
| commitLineBreakClear(); |
| } |
| } |
| } |
| |
| inline TrailingObjects::CollapseFirstSpaceOrNot checkWhitespaceCollapsingTransitions(LineWhitespaceCollapsingState& lineWhitespaceCollapsingState, const InlineIterator& lBreak) |
| { |
| // Check to see if our last transition is a start point beyond the line break. If so, |
| // shave it off the list, and shave off a trailing space if the previous end point doesn't |
| // preserve whitespace. |
| if (lBreak.renderer() && lineWhitespaceCollapsingState.numTransitions() && !(lineWhitespaceCollapsingState.numTransitions() % 2)) { |
| const InlineIterator* transitions = lineWhitespaceCollapsingState.transitions().data(); |
| const InlineIterator& endpoint = transitions[lineWhitespaceCollapsingState.numTransitions() - 2]; |
| const InlineIterator& startpoint = transitions[lineWhitespaceCollapsingState.numTransitions() - 1]; |
| InlineIterator currpoint = endpoint; |
| while (!currpoint.atEnd() && currpoint != startpoint && currpoint != lBreak) |
| currpoint.increment(); |
| if (currpoint == lBreak) { |
| // We hit the line break before the start point. Shave off the start point. |
| lineWhitespaceCollapsingState.decrementNumTransitions(); |
| if (endpoint.renderer()->style().collapseWhiteSpace() && endpoint.renderer()->isText()) { |
| lineWhitespaceCollapsingState.decrementTransitionAt(lineWhitespaceCollapsingState.numTransitions() - 1); |
| return TrailingObjects::DoNotCollapseFirstSpace; |
| } |
| } |
| } |
| return TrailingObjects::CollapseFirstSpace; |
| } |
| |
| inline InlineIterator BreakingContext::handleEndOfLine() |
| { |
| if (m_lineBreak == m_resolver.position()) { |
| if (!m_lineBreak.renderer() || !m_lineBreak.renderer()->isBR()) { |
| // we just add as much as possible |
| if (m_blockStyle.whiteSpace() == WhiteSpace::Pre && !m_current.offset()) { |
| if (m_lastObject) |
| commitLineBreakAtCurrentWidth(*m_lastObject, m_lastObject->isText() ? m_lastObject->length() : 0); |
| else |
| commitLineBreakClear(); |
| } else if (m_lineBreak.renderer()) { |
| // Don't ever break in the middle of a word if we can help it. |
| // There's no room at all. We just have to be on this line, |
| // even though we'll spill out. |
| commitLineBreakAtCurrentWidth(*m_current.renderer(), m_current.offset()); |
| } |
| } |
| // make sure we consume at least one char/object. |
| if (m_lineBreak == m_resolver.position()) |
| m_lineBreak.increment(); |
| } else if (!m_current.offset() && !m_width.committedWidth() && m_width.uncommittedWidth() && !m_hadUncommittedWidthBeforeCurrent) { |
| // Do not push the current object to the next line, when this line has some content, but it is still considered empty. |
| // Empty inline elements like <span></span> can produce such lines and now we just ignore these break opportunities |
| // at the start of a line, if no width has been committed yet. |
| // Behave as if it was actually empty and consume at least one object. |
| m_lineBreak.increment(); |
| } |
| |
| // Sanity check our whitespace collapsing transitions. |
| TrailingObjects::CollapseFirstSpaceOrNot collapsed = checkWhitespaceCollapsingTransitions(m_lineWhitespaceCollapsingState, m_lineBreak); |
| |
| m_trailingObjects.updateWhitespaceCollapsingTransitionsForTrailingBoxes(m_lineWhitespaceCollapsingState, m_lineBreak, collapsed); |
| |
| // We might have made lineBreak an iterator that points past the end |
| // of the object. Do this adjustment to make it point to the start |
| // of the next object instead to avoid confusing the rest of the |
| // code. |
| if (m_lineBreak.offset()) { |
| m_lineBreak.setOffset(m_lineBreak.offset() - 1); |
| m_lineBreak.increment(); |
| } |
| |
| return m_lineBreak; |
| } |
| |
| } |
