| /* |
| * Copyright (C) 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY |
| * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED |
| * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| * DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY |
| * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES |
| * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON |
| * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS |
| * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include "config.h" |
| #include "ComplexTextController.h" |
| |
| #include "CharacterProperties.h" |
| #include "FloatSize.h" |
| #include "FontCascade.h" |
| #include "RenderBlock.h" |
| #include "RenderText.h" |
| #include "TextBreakIterator.h" |
| #include "TextRun.h" |
| #if !PLATFORM(IOS) |
| #include <ApplicationServices/ApplicationServices.h> |
| #else |
| #include <CoreText/CoreText.h> |
| #endif |
| #include <wtf/StdLibExtras.h> |
| #include <wtf/unicode/CharacterNames.h> |
| |
| namespace WebCore { |
| |
| class TextLayout { |
| public: |
| static bool isNeeded(RenderText* text, const FontCascade& font) |
| { |
| TextRun run = RenderBlock::constructTextRun(text, font, text, text->style()); |
| return font.codePath(run) == FontCascade::Complex; |
| } |
| |
| TextLayout(RenderText* text, const FontCascade& font, float xPos) |
| : m_font(font) |
| , m_run(constructTextRun(text, font, xPos)) |
| , m_controller(std::make_unique<ComplexTextController>(m_font, m_run, true)) |
| { |
| } |
| |
| float width(unsigned from, unsigned len, HashSet<const Font*>* fallbackFonts) |
| { |
| m_controller->advance(from, 0, ByWholeGlyphs, fallbackFonts); |
| float beforeWidth = m_controller->runWidthSoFar(); |
| if (m_font.wordSpacing() && from && FontCascade::treatAsSpace(m_run[from])) |
| beforeWidth += m_font.wordSpacing(); |
| m_controller->advance(from + len, 0, ByWholeGlyphs, fallbackFonts); |
| float afterWidth = m_controller->runWidthSoFar(); |
| return afterWidth - beforeWidth; |
| } |
| |
| private: |
| static TextRun constructTextRun(RenderText* text, const FontCascade& font, float xPos) |
| { |
| TextRun run = RenderBlock::constructTextRun(text, font, text, text->style()); |
| run.setCharactersLength(text->textLength()); |
| ASSERT(run.charactersLength() >= run.length()); |
| |
| run.setXPos(xPos); |
| return run; |
| } |
| |
| // ComplexTextController has only references to its FontCascade and TextRun so they must be kept alive here. |
| FontCascade m_font; |
| TextRun m_run; |
| std::unique_ptr<ComplexTextController> m_controller; |
| }; |
| |
| PassOwnPtr<TextLayout> FontCascade::createLayout(RenderText* text, float xPos, bool collapseWhiteSpace) const |
| { |
| if (!collapseWhiteSpace || !TextLayout::isNeeded(text, *this)) |
| return nullptr; |
| return adoptPtr(new TextLayout(text, *this, xPos)); |
| } |
| |
| void FontCascade::deleteLayout(TextLayout* layout) |
| { |
| delete layout; |
| } |
| |
| float FontCascade::width(TextLayout& layout, unsigned from, unsigned len, HashSet<const Font*>* fallbackFonts) |
| { |
| return layout.width(from, len, fallbackFonts); |
| } |
| |
| static inline CGFloat roundCGFloat(CGFloat f) |
| { |
| if (sizeof(CGFloat) == sizeof(float)) |
| return roundf(static_cast<float>(f)); |
| return static_cast<CGFloat>(round(f)); |
| } |
| |
| static inline CGFloat ceilCGFloat(CGFloat f) |
| { |
| if (sizeof(CGFloat) == sizeof(float)) |
| return ceilf(static_cast<float>(f)); |
| return static_cast<CGFloat>(ceil(f)); |
| } |
| |
| ComplexTextController::ComplexTextController(const FontCascade& font, const TextRun& run, bool mayUseNaturalWritingDirection, HashSet<const Font*>* fallbackFonts, bool forTextEmphasis) |
| : m_font(font) |
| , m_run(run) |
| , m_isLTROnly(true) |
| , m_mayUseNaturalWritingDirection(mayUseNaturalWritingDirection) |
| , m_forTextEmphasis(forTextEmphasis) |
| , m_currentCharacter(0) |
| , m_end(run.length()) |
| , m_totalWidth(0) |
| , m_runWidthSoFar(0) |
| , m_numGlyphsSoFar(0) |
| , m_currentRun(0) |
| , m_glyphInCurrentRun(0) |
| , m_characterInCurrentGlyph(0) |
| , m_finalRoundingWidth(0) |
| , m_expansion(run.expansion()) |
| , m_leadingExpansion(0) |
| , m_fallbackFonts(fallbackFonts) |
| , m_minGlyphBoundingBoxX(std::numeric_limits<float>::max()) |
| , m_maxGlyphBoundingBoxX(std::numeric_limits<float>::min()) |
| , m_minGlyphBoundingBoxY(std::numeric_limits<float>::max()) |
| , m_maxGlyphBoundingBoxY(std::numeric_limits<float>::min()) |
| , m_lastRoundingGlyph(0) |
| { |
| if (!m_expansion) |
| m_expansionPerOpportunity = 0; |
| else { |
| unsigned expansionOpportunityCount = FontCascade::expansionOpportunityCount(m_run.text(), m_run.ltr() ? LTR : RTL, run.expansionBehavior()).first; |
| |
| if (!expansionOpportunityCount) |
| m_expansionPerOpportunity = 0; |
| else |
| m_expansionPerOpportunity = m_expansion / expansionOpportunityCount; |
| } |
| |
| collectComplexTextRuns(); |
| adjustGlyphsAndAdvances(); |
| |
| if (!m_isLTROnly) { |
| m_runIndices.reserveInitialCapacity(m_complexTextRuns.size()); |
| |
| m_glyphCountFromStartToIndex.reserveInitialCapacity(m_complexTextRuns.size()); |
| unsigned glyphCountSoFar = 0; |
| for (unsigned i = 0; i < m_complexTextRuns.size(); ++i) { |
| m_glyphCountFromStartToIndex.uncheckedAppend(glyphCountSoFar); |
| glyphCountSoFar += m_complexTextRuns[i]->glyphCount(); |
| } |
| } |
| |
| m_runWidthSoFar = m_leadingExpansion; |
| } |
| |
| int ComplexTextController::offsetForPosition(float h, bool includePartialGlyphs) |
| { |
| if (h >= m_totalWidth) |
| return m_run.ltr() ? m_end : 0; |
| |
| h -= m_leadingExpansion; |
| if (h < 0) |
| return m_run.ltr() ? 0 : m_end; |
| |
| CGFloat x = h; |
| |
| size_t runCount = m_complexTextRuns.size(); |
| size_t offsetIntoAdjustedGlyphs = 0; |
| |
| for (size_t r = 0; r < runCount; ++r) { |
| const ComplexTextRun& complexTextRun = *m_complexTextRuns[r]; |
| for (unsigned j = 0; j < complexTextRun.glyphCount(); ++j) { |
| size_t index = offsetIntoAdjustedGlyphs + j; |
| CGFloat adjustedAdvance = m_adjustedAdvances[index].width; |
| if (!index) |
| adjustedAdvance += complexTextRun.initialAdvance().width; |
| if (x < adjustedAdvance) { |
| CFIndex hitGlyphStart = complexTextRun.indexAt(j); |
| CFIndex hitGlyphEnd; |
| if (m_run.ltr()) |
| hitGlyphEnd = std::max<CFIndex>(hitGlyphStart, j + 1 < complexTextRun.glyphCount() ? complexTextRun.indexAt(j + 1) : static_cast<CFIndex>(complexTextRun.indexEnd())); |
| else |
| hitGlyphEnd = std::max<CFIndex>(hitGlyphStart, j > 0 ? complexTextRun.indexAt(j - 1) : static_cast<CFIndex>(complexTextRun.indexEnd())); |
| |
| // FIXME: Instead of dividing the glyph's advance equally between the characters, this |
| // could use the glyph's "ligature carets". However, there is no Core Text API to get the |
| // ligature carets. |
| CFIndex hitIndex = hitGlyphStart + (hitGlyphEnd - hitGlyphStart) * (m_run.ltr() ? x / adjustedAdvance : 1 - x / adjustedAdvance); |
| int stringLength = complexTextRun.stringLength(); |
| TextBreakIterator* cursorPositionIterator = cursorMovementIterator(StringView(complexTextRun.characters(), stringLength)); |
| int clusterStart; |
| if (isTextBreak(cursorPositionIterator, hitIndex)) |
| clusterStart = hitIndex; |
| else { |
| clusterStart = textBreakPreceding(cursorPositionIterator, hitIndex); |
| if (clusterStart == TextBreakDone) |
| clusterStart = 0; |
| } |
| |
| if (!includePartialGlyphs) |
| return complexTextRun.stringLocation() + clusterStart; |
| |
| int clusterEnd = textBreakFollowing(cursorPositionIterator, hitIndex); |
| if (clusterEnd == TextBreakDone) |
| clusterEnd = stringLength; |
| |
| CGFloat clusterWidth; |
| // FIXME: The search stops at the boundaries of complexTextRun. In theory, it should go on into neighboring ComplexTextRuns |
| // derived from the same CTLine. In practice, we do not expect there to be more than one CTRun in a CTLine, as no |
| // reordering and no font fallback should occur within a CTLine. |
| if (clusterEnd - clusterStart > 1) { |
| clusterWidth = adjustedAdvance; |
| int firstGlyphBeforeCluster = j - 1; |
| while (firstGlyphBeforeCluster >= 0 && complexTextRun.indexAt(firstGlyphBeforeCluster) >= clusterStart && complexTextRun.indexAt(firstGlyphBeforeCluster) < clusterEnd) { |
| CGFloat width = m_adjustedAdvances[offsetIntoAdjustedGlyphs + firstGlyphBeforeCluster].width; |
| clusterWidth += width; |
| x += width; |
| firstGlyphBeforeCluster--; |
| } |
| unsigned firstGlyphAfterCluster = j + 1; |
| while (firstGlyphAfterCluster < complexTextRun.glyphCount() && complexTextRun.indexAt(firstGlyphAfterCluster) >= clusterStart && complexTextRun.indexAt(firstGlyphAfterCluster) < clusterEnd) { |
| clusterWidth += m_adjustedAdvances[offsetIntoAdjustedGlyphs + firstGlyphAfterCluster].width; |
| firstGlyphAfterCluster++; |
| } |
| } else { |
| clusterWidth = adjustedAdvance / (hitGlyphEnd - hitGlyphStart); |
| x -= clusterWidth * (m_run.ltr() ? hitIndex - hitGlyphStart : hitGlyphEnd - hitIndex - 1); |
| } |
| if (x <= clusterWidth / 2) |
| return complexTextRun.stringLocation() + (m_run.ltr() ? clusterStart : clusterEnd); |
| else |
| return complexTextRun.stringLocation() + (m_run.ltr() ? clusterEnd : clusterStart); |
| } |
| x -= adjustedAdvance; |
| } |
| offsetIntoAdjustedGlyphs += complexTextRun.glyphCount(); |
| } |
| |
| ASSERT_NOT_REACHED(); |
| return 0; |
| } |
| |
| // FIXME: We should consider reimplementing this function using ICU to advance by grapheme. |
| // The current implementation only considers explicitly emoji sequences and emoji variations. |
| static bool advanceByCombiningCharacterSequence(const UChar*& iterator, const UChar* end, UChar32& baseCharacter, unsigned& markCount) |
| { |
| ASSERT(iterator < end); |
| |
| markCount = 0; |
| |
| unsigned i = 0; |
| unsigned remainingCharacters = end - iterator; |
| U16_NEXT(iterator, i, remainingCharacters, baseCharacter); |
| iterator = iterator + i; |
| if (U_IS_SURROGATE(baseCharacter)) |
| return false; |
| |
| // Consume marks. |
| bool sawEmojiGroupCandidate = isEmojiGroupCandidate(baseCharacter); |
| bool sawJoiner = false; |
| while (iterator < end) { |
| UChar32 nextCharacter; |
| int markLength = 0; |
| bool shouldContinue = false; |
| U16_NEXT(iterator, markLength, end - iterator, nextCharacter); |
| |
| if (isVariationSelector(nextCharacter) || isEmojiModifier(nextCharacter)) |
| shouldContinue = true; |
| |
| if (sawJoiner && isEmojiGroupCandidate(nextCharacter)) |
| shouldContinue = true; |
| |
| sawJoiner = false; |
| if (sawEmojiGroupCandidate && nextCharacter == zeroWidthJoiner) { |
| sawJoiner = true; |
| shouldContinue = true; |
| } |
| |
| if (!shouldContinue && !(U_GET_GC_MASK(nextCharacter) & U_GC_M_MASK)) |
| break; |
| |
| markCount += markLength; |
| iterator += markLength; |
| } |
| |
| return true; |
| } |
| |
| void ComplexTextController::collectComplexTextRuns() |
| { |
| if (!m_end) |
| return; |
| |
| // We break up glyph run generation for the string by Font. |
| const UChar* cp; |
| |
| if (m_run.is8Bit()) { |
| String stringFor8BitRun = String::make16BitFrom8BitSource(m_run.characters8(), m_run.length()); |
| cp = stringFor8BitRun.characters16(); |
| m_stringsFor8BitRuns.append(stringFor8BitRun); |
| } else |
| cp = m_run.characters16(); |
| |
| if (m_font.isSmallCaps()) |
| m_smallCapsBuffer.resize(m_end); |
| |
| unsigned indexOfFontTransition = 0; |
| const UChar* curr = cp; |
| const UChar* end = cp + m_end; |
| |
| const Font* font; |
| bool isMissingGlyph; |
| const Font* nextFont; |
| bool nextIsMissingGlyph; |
| |
| unsigned markCount; |
| const UChar* sequenceStart = curr; |
| UChar32 baseCharacter; |
| if (!advanceByCombiningCharacterSequence(curr, end, baseCharacter, markCount)) |
| return; |
| |
| UChar uppercaseCharacter = 0; |
| |
| bool isSmallCaps; |
| bool nextIsSmallCaps = m_font.isSmallCaps() && !(U_GET_GC_MASK(baseCharacter) & U_GC_M_MASK) && (uppercaseCharacter = u_toupper(baseCharacter)) != baseCharacter; |
| ASSERT(uppercaseCharacter == 0 || u_toupper(baseCharacter) <= 0xFFFF); |
| |
| if (nextIsSmallCaps) { |
| m_smallCapsBuffer[sequenceStart - cp] = uppercaseCharacter; |
| for (unsigned i = 0; i < markCount; ++i) |
| m_smallCapsBuffer[sequenceStart - cp + i + 1] = sequenceStart[i + 1]; |
| } |
| |
| nextIsMissingGlyph = false; |
| nextFont = m_font.fontForCombiningCharacterSequence(sequenceStart, curr - sequenceStart, nextIsSmallCaps ? SmallCapsVariant : NormalVariant); |
| if (!nextFont) |
| nextIsMissingGlyph = true; |
| |
| while (curr < end) { |
| font = nextFont; |
| isMissingGlyph = nextIsMissingGlyph; |
| isSmallCaps = nextIsSmallCaps; |
| int index = curr - cp; |
| |
| if (!advanceByCombiningCharacterSequence(curr, end, baseCharacter, markCount)) |
| return; |
| |
| if (m_font.isSmallCaps()) { |
| ASSERT(u_toupper(baseCharacter) <= 0xFFFF); |
| uppercaseCharacter = u_toupper(baseCharacter); |
| nextIsSmallCaps = uppercaseCharacter != baseCharacter; |
| if (nextIsSmallCaps) { |
| m_smallCapsBuffer[index] = uppercaseCharacter; |
| for (unsigned i = 0; i < markCount; ++i) |
| m_smallCapsBuffer[index + i + 1] = cp[index + i + 1]; |
| } |
| } |
| |
| nextIsMissingGlyph = false; |
| if (baseCharacter == zeroWidthJoiner) |
| nextFont = font; |
| else { |
| nextFont = m_font.fontForCombiningCharacterSequence(cp + index, curr - cp - index, nextIsSmallCaps ? SmallCapsVariant : NormalVariant); |
| if (!nextFont) |
| nextIsMissingGlyph = true; |
| } |
| |
| if (nextFont != font || nextIsMissingGlyph != isMissingGlyph) { |
| int itemStart = static_cast<int>(indexOfFontTransition); |
| int itemLength = index - indexOfFontTransition; |
| collectComplexTextRunsForCharacters((isSmallCaps ? m_smallCapsBuffer.data() : cp) + itemStart, itemLength, itemStart, !isMissingGlyph ? font : 0); |
| indexOfFontTransition = index; |
| } |
| } |
| |
| int itemLength = m_end - indexOfFontTransition; |
| if (itemLength) { |
| int itemStart = indexOfFontTransition; |
| collectComplexTextRunsForCharacters((nextIsSmallCaps ? m_smallCapsBuffer.data() : cp) + itemStart, itemLength, itemStart, !nextIsMissingGlyph ? nextFont : 0); |
| } |
| |
| if (!m_run.ltr()) |
| m_complexTextRuns.reverse(); |
| } |
| |
| CFIndex ComplexTextController::ComplexTextRun::indexAt(size_t i) const |
| { |
| ASSERT(i < m_glyphCount); |
| |
| return m_coreTextIndices[i]; |
| } |
| |
| void ComplexTextController::ComplexTextRun::setIsNonMonotonic() |
| { |
| ASSERT(m_isMonotonic); |
| m_isMonotonic = false; |
| |
| Vector<bool, 64> mappedIndices(m_stringLength); |
| for (size_t i = 0; i < m_glyphCount; ++i) { |
| ASSERT(indexAt(i) < static_cast<CFIndex>(m_stringLength)); |
| mappedIndices[indexAt(i)] = true; |
| } |
| |
| m_glyphEndOffsets.grow(m_glyphCount); |
| for (size_t i = 0; i < m_glyphCount; ++i) { |
| CFIndex nextMappedIndex = m_indexEnd; |
| for (size_t j = indexAt(i) + 1; j < m_stringLength; ++j) { |
| if (mappedIndices[j]) { |
| nextMappedIndex = j; |
| break; |
| } |
| } |
| m_glyphEndOffsets[i] = nextMappedIndex; |
| } |
| } |
| |
| unsigned ComplexTextController::indexOfCurrentRun(unsigned& leftmostGlyph) |
| { |
| leftmostGlyph = 0; |
| |
| size_t runCount = m_complexTextRuns.size(); |
| if (m_currentRun >= runCount) |
| return runCount; |
| |
| if (m_isLTROnly) { |
| for (unsigned i = 0; i < m_currentRun; ++i) |
| leftmostGlyph += m_complexTextRuns[i]->glyphCount(); |
| return m_currentRun; |
| } |
| |
| if (m_runIndices.isEmpty()) { |
| unsigned firstRun = 0; |
| unsigned firstRunOffset = stringBegin(*m_complexTextRuns[0]); |
| for (unsigned i = 1; i < runCount; ++i) { |
| unsigned offset = stringBegin(*m_complexTextRuns[i]); |
| if (offset < firstRunOffset) { |
| firstRun = i; |
| firstRunOffset = offset; |
| } |
| } |
| m_runIndices.uncheckedAppend(firstRun); |
| } |
| |
| while (m_runIndices.size() <= m_currentRun) { |
| unsigned offset = stringEnd(*m_complexTextRuns[m_runIndices.last()]); |
| |
| for (unsigned i = 0; i < runCount; ++i) { |
| if (offset == stringBegin(*m_complexTextRuns[i])) { |
| m_runIndices.uncheckedAppend(i); |
| break; |
| } |
| } |
| } |
| |
| unsigned currentRunIndex = m_runIndices[m_currentRun]; |
| leftmostGlyph = m_glyphCountFromStartToIndex[currentRunIndex]; |
| return currentRunIndex; |
| } |
| |
| unsigned ComplexTextController::incrementCurrentRun(unsigned& leftmostGlyph) |
| { |
| if (m_isLTROnly) { |
| leftmostGlyph += m_complexTextRuns[m_currentRun++]->glyphCount(); |
| return m_currentRun; |
| } |
| |
| m_currentRun++; |
| leftmostGlyph = 0; |
| return indexOfCurrentRun(leftmostGlyph); |
| } |
| |
| void ComplexTextController::advance(unsigned offset, GlyphBuffer* glyphBuffer, GlyphIterationStyle iterationStyle, HashSet<const Font*>* fallbackFonts) |
| { |
| if (static_cast<int>(offset) > m_end) |
| offset = m_end; |
| |
| if (offset <= m_currentCharacter) { |
| m_runWidthSoFar = m_leadingExpansion; |
| m_numGlyphsSoFar = 0; |
| m_currentRun = 0; |
| m_glyphInCurrentRun = 0; |
| m_characterInCurrentGlyph = 0; |
| } |
| |
| m_currentCharacter = offset; |
| |
| size_t runCount = m_complexTextRuns.size(); |
| |
| unsigned leftmostGlyph = 0; |
| unsigned currentRunIndex = indexOfCurrentRun(leftmostGlyph); |
| while (m_currentRun < runCount) { |
| const ComplexTextRun& complexTextRun = *m_complexTextRuns[currentRunIndex]; |
| bool ltr = complexTextRun.isLTR(); |
| size_t glyphCount = complexTextRun.glyphCount(); |
| unsigned g = ltr ? m_glyphInCurrentRun : glyphCount - 1 - m_glyphInCurrentRun; |
| unsigned k = leftmostGlyph + g; |
| if (fallbackFonts && &complexTextRun.font() != &m_font.primaryFont()) |
| fallbackFonts->add(&complexTextRun.font()); |
| |
| // We must store the initial advance for the first glyph we are going to draw. |
| // When leftmostGlyph is 0, it represents the first glyph to draw, taking into |
| // account the text direction. |
| if (glyphBuffer && !leftmostGlyph) { |
| glyphBuffer->setInitialAdvance(complexTextRun.initialAdvance()); |
| glyphBuffer->setLeadingExpansion(m_leadingExpansion); |
| } |
| |
| while (m_glyphInCurrentRun < glyphCount) { |
| unsigned glyphStartOffset = complexTextRun.indexAt(g); |
| unsigned glyphEndOffset; |
| if (complexTextRun.isMonotonic()) { |
| if (ltr) |
| glyphEndOffset = std::max<unsigned>(glyphStartOffset, static_cast<unsigned>(g + 1 < glyphCount ? complexTextRun.indexAt(g + 1) : complexTextRun.indexEnd())); |
| else |
| glyphEndOffset = std::max<unsigned>(glyphStartOffset, static_cast<unsigned>(g > 0 ? complexTextRun.indexAt(g - 1) : complexTextRun.indexEnd())); |
| } else |
| glyphEndOffset = complexTextRun.endOffsetAt(g); |
| |
| CGSize adjustedAdvance = m_adjustedAdvances[k]; |
| |
| if (glyphStartOffset + complexTextRun.stringLocation() >= m_currentCharacter) |
| return; |
| |
| if (glyphBuffer && !m_characterInCurrentGlyph) |
| glyphBuffer->add(m_adjustedGlyphs[k], &complexTextRun.font(), adjustedAdvance, complexTextRun.indexAt(m_glyphInCurrentRun)); |
| |
| unsigned oldCharacterInCurrentGlyph = m_characterInCurrentGlyph; |
| m_characterInCurrentGlyph = std::min(m_currentCharacter - complexTextRun.stringLocation(), glyphEndOffset) - glyphStartOffset; |
| // FIXME: Instead of dividing the glyph's advance equally between the characters, this |
| // could use the glyph's "ligature carets". However, there is no Core Text API to get the |
| // ligature carets. |
| if (glyphStartOffset == glyphEndOffset) { |
| // When there are multiple glyphs per character we need to advance by the full width of the glyph. |
| ASSERT(m_characterInCurrentGlyph == oldCharacterInCurrentGlyph); |
| m_runWidthSoFar += adjustedAdvance.width; |
| } else if (iterationStyle == ByWholeGlyphs) { |
| if (!oldCharacterInCurrentGlyph) |
| m_runWidthSoFar += adjustedAdvance.width; |
| } else |
| m_runWidthSoFar += adjustedAdvance.width * (m_characterInCurrentGlyph - oldCharacterInCurrentGlyph) / (glyphEndOffset - glyphStartOffset); |
| |
| if (glyphEndOffset + complexTextRun.stringLocation() > m_currentCharacter) |
| return; |
| |
| m_numGlyphsSoFar++; |
| m_glyphInCurrentRun++; |
| m_characterInCurrentGlyph = 0; |
| if (ltr) { |
| g++; |
| k++; |
| } else { |
| g--; |
| k--; |
| } |
| } |
| currentRunIndex = incrementCurrentRun(leftmostGlyph); |
| m_glyphInCurrentRun = 0; |
| } |
| if (!m_run.ltr() && m_numGlyphsSoFar == m_adjustedAdvances.size()) |
| m_runWidthSoFar += m_finalRoundingWidth; |
| } |
| |
| static inline std::pair<bool, bool> expansionLocation(bool ideograph, bool treatAsSpace, bool ltr, bool isAfterExpansion, bool forbidLeadingExpansion, bool forbidTrailingExpansion, bool forceLeadingExpansion, bool forceTrailingExpansion) |
| { |
| bool expandLeft = ideograph; |
| bool expandRight = ideograph; |
| if (treatAsSpace) { |
| if (ltr) |
| expandRight = true; |
| else |
| expandLeft = true; |
| } |
| if (isAfterExpansion) |
| expandLeft = false; |
| ASSERT(!forbidLeadingExpansion || !forceLeadingExpansion); |
| ASSERT(!forbidTrailingExpansion || !forceTrailingExpansion); |
| if (forbidLeadingExpansion) |
| expandLeft = false; |
| if (forbidTrailingExpansion) |
| expandRight = false; |
| if (forceLeadingExpansion) |
| expandLeft = true; |
| if (forceTrailingExpansion) |
| expandRight = true; |
| return std::make_pair(expandLeft, expandRight); |
| } |
| |
| void ComplexTextController::adjustGlyphsAndAdvances() |
| { |
| bool afterExpansion = (m_run.expansionBehavior() & LeadingExpansionMask) == ForbidLeadingExpansion; |
| CGFloat widthSinceLastCommit = 0; |
| size_t runCount = m_complexTextRuns.size(); |
| bool hasExtraSpacing = (m_font.letterSpacing() || m_font.wordSpacing() || m_expansion) && !m_run.spacingDisabled(); |
| bool runForcesLeadingExpansion = (m_run.expansionBehavior() & LeadingExpansionMask) == ForceLeadingExpansion; |
| bool runForcesTrailingExpansion = (m_run.expansionBehavior() & TrailingExpansionMask) == ForceTrailingExpansion; |
| bool runForbidsLeadingExpansion = (m_run.expansionBehavior() & LeadingExpansionMask) == ForbidLeadingExpansion; |
| bool runForbidsTrailingExpansion = (m_run.expansionBehavior() & TrailingExpansionMask) == ForbidTrailingExpansion; |
| // We are iterating in glyph order, not string order. Compare this to WidthIterator::advanceInternal() |
| for (size_t r = 0; r < runCount; ++r) { |
| ComplexTextRun& complexTextRun = *m_complexTextRuns[r]; |
| unsigned glyphCount = complexTextRun.glyphCount(); |
| const Font& font = complexTextRun.font(); |
| #if PLATFORM(IOS) |
| bool isEmoji = font.platformData().m_isEmoji; |
| #endif |
| |
| // Represent the initial advance for a text run by adjusting the advance |
| // of the last glyph of the previous text run in the glyph buffer. |
| if (r && m_adjustedAdvances.size()) { |
| CGSize previousAdvance = m_adjustedAdvances.last(); |
| previousAdvance.width += complexTextRun.initialAdvance().width; |
| previousAdvance.height -= complexTextRun.initialAdvance().height; |
| m_adjustedAdvances[m_adjustedAdvances.size() - 1] = previousAdvance; |
| } |
| widthSinceLastCommit += complexTextRun.initialAdvance().width; |
| |
| if (!complexTextRun.isLTR()) |
| m_isLTROnly = false; |
| |
| const CGGlyph* glyphs = complexTextRun.glyphs(); |
| const CGSize* advances = complexTextRun.advances(); |
| |
| bool lastRun = r + 1 == runCount; |
| float spaceWidth = font.spaceWidth() - font.syntheticBoldOffset(); |
| CGFloat roundedSpaceWidth = roundCGFloat(spaceWidth); |
| const UChar* cp = complexTextRun.characters(); |
| CGPoint glyphOrigin = CGPointZero; |
| CFIndex lastCharacterIndex = m_run.ltr() ? std::numeric_limits<CFIndex>::min() : std::numeric_limits<CFIndex>::max(); |
| bool isMonotonic = true; |
| |
| for (unsigned i = 0; i < glyphCount; i++) { |
| CFIndex characterIndex = complexTextRun.indexAt(i); |
| if (m_run.ltr()) { |
| if (characterIndex < lastCharacterIndex) |
| isMonotonic = false; |
| } else { |
| if (characterIndex > lastCharacterIndex) |
| isMonotonic = false; |
| } |
| UChar ch = *(cp + characterIndex); |
| bool lastGlyph = lastRun && i + 1 == glyphCount; |
| UChar nextCh; |
| if (lastGlyph) |
| nextCh = ' '; |
| else if (i + 1 < glyphCount) |
| nextCh = *(cp + complexTextRun.indexAt(i + 1)); |
| else |
| nextCh = *(m_complexTextRuns[r + 1]->characters() + m_complexTextRuns[r + 1]->indexAt(0)); |
| |
| bool treatAsSpace = FontCascade::treatAsSpace(ch); |
| CGGlyph glyph = treatAsSpace ? font.spaceGlyph() : glyphs[i]; |
| CGSize advance = treatAsSpace ? CGSizeMake(spaceWidth, advances[i].height) : advances[i]; |
| #if PLATFORM(IOS) |
| if (isEmoji && advance.width) |
| advance.width = font.widthForGlyph(glyph); |
| #endif |
| |
| if (ch == '\t' && m_run.allowTabs()) |
| advance.width = m_font.tabWidth(font, m_run.tabSize(), m_run.xPos() + m_totalWidth + widthSinceLastCommit); |
| else if (FontCascade::treatAsZeroWidthSpace(ch) && !treatAsSpace) { |
| advance.width = 0; |
| glyph = font.spaceGlyph(); |
| } |
| |
| float roundedAdvanceWidth = roundf(advance.width); |
| advance.width += font.syntheticBoldOffset(); |
| |
| |
| // We special case spaces in two ways when applying word rounding. |
| // First, we round spaces to an adjusted width in all fonts. |
| // Second, in fixed-pitch fonts we ensure that all glyphs that |
| // match the width of the space glyph have the same width as the space glyph. |
| if (m_run.applyWordRounding() && roundedAdvanceWidth == roundedSpaceWidth && (font.pitch() == FixedPitch || glyph == font.spaceGlyph())) |
| advance.width = font.adjustedSpaceWidth(); |
| |
| if (hasExtraSpacing) { |
| // If we're a glyph with an advance, go ahead and add in letter-spacing. |
| // That way we weed out zero width lurkers. This behavior matches the fast text code path. |
| if (advance.width) |
| advance.width += m_font.letterSpacing(); |
| |
| bool lastCharacter = static_cast<unsigned>(characterIndex + 1) == m_run.length() || (U16_IS_SURROGATE_LEAD(ch) && static_cast<unsigned>(characterIndex + 2) == m_run.length() && U16_IS_SURROGATE_TRAIL(*(cp + characterIndex + 1))); |
| |
| bool forceLeadingExpansion = false; // On the left, regardless of m_run.ltr() |
| bool forceTrailingExpansion = false; // On the right, regardless of m_run.ltr() |
| bool forbidLeadingExpansion = false; |
| bool forbidTrailingExpansion = false; |
| if (runForcesLeadingExpansion) |
| forceLeadingExpansion = m_run.ltr() ? !characterIndex : lastCharacter; |
| if (runForcesTrailingExpansion) |
| forceTrailingExpansion = m_run.ltr() ? lastCharacter : !characterIndex; |
| if (runForbidsLeadingExpansion) |
| forbidLeadingExpansion = m_run.ltr() ? !characterIndex : lastCharacter; |
| if (runForbidsTrailingExpansion) |
| forbidTrailingExpansion = m_run.ltr() ? lastCharacter : !characterIndex; |
| // Handle justification and word-spacing. |
| bool ideograph = FontCascade::isCJKIdeographOrSymbol(ch); |
| if (treatAsSpace || ideograph || forceLeadingExpansion || forceTrailingExpansion) { |
| // Distribute the run's total expansion evenly over all expansion opportunities in the run. |
| if (m_expansion) { |
| bool expandLeft, expandRight; |
| std::tie(expandLeft, expandRight) = expansionLocation(ideograph, treatAsSpace, m_run.ltr(), afterExpansion, forbidLeadingExpansion, forbidTrailingExpansion, forceLeadingExpansion, forceTrailingExpansion); |
| float previousExpansion = m_expansion; |
| if (expandLeft) { |
| // Increase previous width |
| m_expansion -= m_expansionPerOpportunity; |
| float expansionAtThisOpportunity = !m_run.applyWordRounding() ? m_expansionPerOpportunity : roundf(previousExpansion) - roundf(m_expansion); |
| m_totalWidth += expansionAtThisOpportunity; |
| if (m_adjustedAdvances.isEmpty()) |
| m_leadingExpansion = expansionAtThisOpportunity; |
| else |
| m_adjustedAdvances.last().width += expansionAtThisOpportunity; |
| previousExpansion = m_expansion; |
| } |
| if (expandRight) { |
| m_expansion -= m_expansionPerOpportunity; |
| float expansionAtThisOpportunity = !m_run.applyWordRounding() ? m_expansionPerOpportunity : roundf(previousExpansion) - roundf(m_expansion); |
| advance.width += expansionAtThisOpportunity; |
| afterExpansion = true; |
| } |
| } else |
| afterExpansion = false; |
| |
| // Account for word-spacing. |
| if (treatAsSpace && (ch != '\t' || !m_run.allowTabs()) && (characterIndex > 0 || r > 0) && m_font.wordSpacing()) |
| advance.width += m_font.wordSpacing(); |
| } else |
| afterExpansion = false; |
| } |
| |
| // Apply rounding hacks if needed. |
| // We adjust the width of the last character of a "word" to ensure an integer width. |
| // Force characters that are used to determine word boundaries for the rounding hack |
| // to be integer width, so the following words will start on an integer boundary. |
| if (m_run.applyWordRounding() && FontCascade::isRoundingHackCharacter(ch)) |
| advance.width = ceilCGFloat(advance.width); |
| |
| // Check to see if the next character is a "rounding hack character", if so, adjust the |
| // width so that the total run width will be on an integer boundary. |
| bool needsRoundingForCharacter = m_run.applyWordRounding() && !lastGlyph && FontCascade::isRoundingHackCharacter(nextCh); |
| if (needsRoundingForCharacter || (m_run.applyRunRounding() && lastGlyph)) { |
| CGFloat totalWidth = widthSinceLastCommit + advance.width; |
| widthSinceLastCommit = ceilCGFloat(totalWidth); |
| CGFloat extraWidth = widthSinceLastCommit - totalWidth; |
| if (m_run.ltr()) |
| advance.width += extraWidth; |
| else { |
| if (m_lastRoundingGlyph) |
| m_adjustedAdvances[m_lastRoundingGlyph - 1].width += extraWidth; |
| else |
| m_finalRoundingWidth = extraWidth; |
| m_lastRoundingGlyph = m_adjustedAdvances.size() + 1; |
| } |
| m_totalWidth += widthSinceLastCommit; |
| widthSinceLastCommit = 0; |
| } else |
| widthSinceLastCommit += advance.width; |
| |
| // FIXME: Combining marks should receive a text emphasis mark if they are combine with a space. |
| if (m_forTextEmphasis && (!FontCascade::canReceiveTextEmphasis(ch) || (U_GET_GC_MASK(ch) & U_GC_M_MASK))) |
| glyph = 0; |
| |
| advance.height *= -1; |
| m_adjustedAdvances.append(advance); |
| m_adjustedGlyphs.append(glyph); |
| |
| FloatRect glyphBounds = font.boundsForGlyph(glyph); |
| glyphBounds.move(glyphOrigin.x, glyphOrigin.y); |
| m_minGlyphBoundingBoxX = std::min(m_minGlyphBoundingBoxX, glyphBounds.x()); |
| m_maxGlyphBoundingBoxX = std::max(m_maxGlyphBoundingBoxX, glyphBounds.maxX()); |
| m_minGlyphBoundingBoxY = std::min(m_minGlyphBoundingBoxY, glyphBounds.y()); |
| m_maxGlyphBoundingBoxY = std::max(m_maxGlyphBoundingBoxY, glyphBounds.maxY()); |
| glyphOrigin.x += advance.width; |
| glyphOrigin.y += advance.height; |
| |
| lastCharacterIndex = characterIndex; |
| } |
| if (!isMonotonic) |
| complexTextRun.setIsNonMonotonic(); |
| } |
| |
| m_totalWidth += widthSinceLastCommit; |
| } |
| |
| } // namespace WebCore |
