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/*
* Copyright (C) 2007, 2008, 2009 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 "CharacterNames.h"
#include "Font.h"
#include "TextBreakIterator.h"
#include <wtf/StdLibExtras.h>
#if defined(BUILDING_ON_LEOPARD)
// Undefined when compiling agains the 10.5 SDK.
#define kCTVersionNumber10_6 0x00030000
#endif
using namespace std;
namespace WebCore {
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 Font* font, const TextRun& run, bool mayUseNaturalWritingDirection, HashSet<const SimpleFontData*>* fallbackFonts)
: m_font(*font)
, m_run(run)
, m_mayUseNaturalWritingDirection(mayUseNaturalWritingDirection)
, 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_fallbackFonts(fallbackFonts)
, m_lastRoundingGlyph(0)
{
m_padding = m_run.padding();
if (!m_padding)
m_padPerSpace = 0;
else {
float numSpaces = 0;
for (int s = 0; s < m_run.length(); s++)
if (Font::treatAsSpace(m_run[s]))
numSpaces++;
if (numSpaces == 0)
m_padPerSpace = 0;
else
m_padPerSpace = ceilf(m_run.padding() / numSpaces);
}
collectComplexTextRuns();
adjustGlyphsAndAdvances();
}
int ComplexTextController::offsetForPosition(int h, bool includePartialGlyphs)
{
if (h >= m_totalWidth)
return m_run.ltr() ? m_end : 0;
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) {
CGFloat adjustedAdvance = m_adjustedAdvances[offsetIntoAdjustedGlyphs + j].width;
if (x < adjustedAdvance) {
CFIndex hitGlyphStart = complexTextRun.indexAt(j);
CFIndex hitGlyphEnd;
if (m_run.ltr())
hitGlyphEnd = max<CFIndex>(hitGlyphStart, j + 1 < complexTextRun.glyphCount() ? complexTextRun.indexAt(j + 1) : complexTextRun.stringLength());
else
hitGlyphEnd = max<CFIndex>(hitGlyphStart, j > 0 ? complexTextRun.indexAt(j - 1) : complexTextRun.stringLength());
// 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(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 on 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;
}
void ComplexTextController::collectComplexTextRuns()
{
if (!m_end)
return;
// We break up glyph run generation for the string by FontData and (if needed) the use of small caps.
const UChar* cp = m_run.characters();
bool hasTrailingSoftHyphen = m_run[m_end - 1] == softHyphen;
if (m_font.isSmallCaps() || hasTrailingSoftHyphen)
m_smallCapsBuffer.resize(m_end);
unsigned indexOfFontTransition = m_run.rtl() ? m_end - 1 : 0;
const UChar* curr = m_run.rtl() ? cp + m_end - 1 : cp;
const UChar* end = m_run.rtl() ? cp - 1 : cp + m_end;
// FIXME: Using HYPHEN-MINUS rather than HYPHEN because Times has a HYPHEN-MINUS glyph that looks like its
// SOFT-HYPHEN glyph, and has no HYPHEN glyph.
static const UChar hyphen = '-';
if (hasTrailingSoftHyphen && m_run.rtl()) {
collectComplexTextRunsForCharacters(&hyphen, 1, m_end - 1, m_font.glyphDataForCharacter(hyphen, false).fontData);
indexOfFontTransition--;
curr--;
}
GlyphData glyphData;
GlyphData nextGlyphData;
bool isSurrogate = U16_IS_SURROGATE(*curr);
if (isSurrogate) {
if (m_run.ltr()) {
if (!U16_IS_SURROGATE_LEAD(curr[0]) || curr + 1 == end || !U16_IS_TRAIL(curr[1]))
return;
nextGlyphData = m_font.glyphDataForCharacter(U16_GET_SUPPLEMENTARY(curr[0], curr[1]), false);
} else {
if (!U16_IS_TRAIL(curr[0]) || curr -1 == end || !U16_IS_SURROGATE_LEAD(curr[-1]))
return;
nextGlyphData = m_font.glyphDataForCharacter(U16_GET_SUPPLEMENTARY(curr[-1], curr[0]), false);
}
} else
nextGlyphData = m_font.glyphDataForCharacter(*curr, false);
UChar newC = 0;
bool isSmallCaps;
bool nextIsSmallCaps = !isSurrogate && m_font.isSmallCaps() && !(U_GET_GC_MASK(*curr) & U_GC_M_MASK) && (newC = u_toupper(*curr)) != *curr;
if (nextIsSmallCaps)
m_smallCapsBuffer[curr - cp] = newC;
while (true) {
curr = m_run.rtl() ? curr - (isSurrogate ? 2 : 1) : curr + (isSurrogate ? 2 : 1);
if (curr == end)
break;
glyphData = nextGlyphData;
isSmallCaps = nextIsSmallCaps;
int index = curr - cp;
isSurrogate = U16_IS_SURROGATE(*curr);
UChar c = *curr;
bool forceSmallCaps = !isSurrogate && isSmallCaps && (U_GET_GC_MASK(c) & U_GC_M_MASK);
if (isSurrogate) {
if (m_run.ltr()) {
if (!U16_IS_SURROGATE_LEAD(curr[0]) || curr + 1 == end || !U16_IS_TRAIL(curr[1]))
return;
nextGlyphData = m_font.glyphDataForCharacter(U16_GET_SUPPLEMENTARY(curr[0], curr[1]), false);
} else {
if (!U16_IS_TRAIL(curr[0]) || curr -1 == end || !U16_IS_SURROGATE_LEAD(curr[-1]))
return;
nextGlyphData = m_font.glyphDataForCharacter(U16_GET_SUPPLEMENTARY(curr[-1], curr[0]), false);
}
} else
nextGlyphData = m_font.glyphDataForCharacter(*curr, false, forceSmallCaps);
if (!isSurrogate && m_font.isSmallCaps()) {
nextIsSmallCaps = forceSmallCaps || (newC = u_toupper(c)) != c;
if (nextIsSmallCaps)
m_smallCapsBuffer[index] = forceSmallCaps ? c : newC;
}
if (nextGlyphData.fontData != glyphData.fontData || nextIsSmallCaps != isSmallCaps || !nextGlyphData.glyph != !glyphData.glyph) {
int itemStart = m_run.rtl() ? index + 1 : indexOfFontTransition;
int itemLength = m_run.rtl() ? indexOfFontTransition - index : index - indexOfFontTransition;
collectComplexTextRunsForCharacters((isSmallCaps ? m_smallCapsBuffer.data() : cp) + itemStart, itemLength, itemStart, glyphData.glyph ? glyphData.fontData : 0);
indexOfFontTransition = index;
}
}
int itemLength = m_run.rtl() ? indexOfFontTransition + 1 : m_end - indexOfFontTransition - (hasTrailingSoftHyphen ? 1 : 0);
if (itemLength) {
int itemStart = m_run.rtl() ? 0 : indexOfFontTransition;
collectComplexTextRunsForCharacters((nextIsSmallCaps ? m_smallCapsBuffer.data() : cp) + itemStart, itemLength, itemStart, nextGlyphData.glyph ? nextGlyphData.fontData : 0);
}
if (hasTrailingSoftHyphen && m_run.ltr())
collectComplexTextRunsForCharacters(&hyphen, 1, m_end - 1, m_font.glyphDataForCharacter(hyphen, false).fontData);
}
#if USE(CORE_TEXT) && USE(ATSUI)
static inline bool shouldUseATSUIAPI()
{
enum TypeRenderingAPIToUse { UnInitialized, UseATSUI, UseCoreText };
DEFINE_STATIC_LOCAL(TypeRenderingAPIToUse, apiToUse, (UnInitialized));
if (UNLIKELY(apiToUse == UnInitialized)) {
if (&CTGetCoreTextVersion != 0 && CTGetCoreTextVersion() >= kCTVersionNumber10_6)
apiToUse = UseCoreText;
else
apiToUse = UseATSUI;
}
return apiToUse == UseATSUI;
}
#endif
CFIndex ComplexTextController::ComplexTextRun::indexAt(size_t i) const
{
#if USE(CORE_TEXT) && USE(ATSUI)
return shouldUseATSUIAPI() ? m_atsuiIndices[i] : m_coreTextIndices[i];
#elif USE(ATSUI)
return m_atsuiIndices[i];
#elif USE(CORE_TEXT)
return m_coreTextIndices[i];
#endif
}
void ComplexTextController::collectComplexTextRunsForCharacters(const UChar* cp, unsigned length, unsigned stringLocation, const SimpleFontData* fontData)
{
#if USE(CORE_TEXT) && USE(ATSUI)
if (shouldUseATSUIAPI())
return collectComplexTextRunsForCharactersATSUI(cp, length, stringLocation, fontData);
return collectComplexTextRunsForCharactersCoreText(cp, length, stringLocation, fontData);
#elif USE(ATSUI)
return collectComplexTextRunsForCharactersATSUI(cp, length, stringLocation, fontData);
#elif USE(CORE_TEXT)
return collectComplexTextRunsForCharactersCoreText(cp, length, stringLocation, fontData);
#endif
}
ComplexTextController::ComplexTextRun::ComplexTextRun(const SimpleFontData* fontData, const UChar* characters, unsigned stringLocation, size_t stringLength, bool ltr)
: m_fontData(fontData)
, m_characters(characters)
, m_stringLocation(stringLocation)
, m_stringLength(stringLength)
, m_isMonotonic(true)
{
#if USE(CORE_TEXT) && USE(ATSUI)
shouldUseATSUIAPI() ? createTextRunFromFontDataATSUI(ltr) : createTextRunFromFontDataCoreText(ltr);
#elif USE(ATSUI)
createTextRunFromFontDataATSUI(ltr);
#elif USE(CORE_TEXT)
createTextRunFromFontDataCoreText(ltr);
#endif
}
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_stringLength;
for (size_t j = indexAt(i) + 1; j < m_stringLength; ++j) {
if (mappedIndices[j]) {
nextMappedIndex = j;
break;
}
}
m_glyphEndOffsets[i] = nextMappedIndex;
}
}
void ComplexTextController::advance(unsigned offset, GlyphBuffer* glyphBuffer)
{
if (static_cast<int>(offset) > m_end)
offset = m_end;
if (offset <= m_currentCharacter)
return;
m_currentCharacter = offset;
size_t runCount = m_complexTextRuns.size();
bool ltr = m_run.ltr();
unsigned k = ltr ? m_numGlyphsSoFar : m_adjustedGlyphs.size() - 1 - m_numGlyphsSoFar;
while (m_currentRun < runCount) {
const ComplexTextRun& complexTextRun = *m_complexTextRuns[ltr ? m_currentRun : runCount - 1 - m_currentRun];
size_t glyphCount = complexTextRun.glyphCount();
unsigned g = ltr ? m_glyphInCurrentRun : glyphCount - 1 - m_glyphInCurrentRun;
while (m_glyphInCurrentRun < glyphCount) {
unsigned glyphStartOffset = complexTextRun.indexAt(g);
unsigned glyphEndOffset;
if (complexTextRun.isMonotonic()) {
if (ltr)
glyphEndOffset = max<unsigned>(glyphStartOffset, g + 1 < glyphCount ? complexTextRun.indexAt(g + 1) : complexTextRun.stringLength());
else
glyphEndOffset = max<unsigned>(glyphStartOffset, g > 0 ? complexTextRun.indexAt(g - 1) : complexTextRun.stringLength());
} 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.fontData(), adjustedAdvance);
unsigned oldCharacterInCurrentGlyph = m_characterInCurrentGlyph;
m_characterInCurrentGlyph = min(m_currentCharacter - complexTextRun.stringLocation(), glyphEndOffset) - glyphStartOffset;
// FIXME: Instead of dividing the glyph's advance equially between the characters, this
// could use the glyph's "ligature carets". However, there is no Core Text API to get the
// ligature carets.
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--;
}
}
m_currentRun++;
m_glyphInCurrentRun = 0;
}
if (!ltr && m_numGlyphsSoFar == m_adjustedAdvances.size())
m_runWidthSoFar += m_finalRoundingWidth;
}
void ComplexTextController::adjustGlyphsAndAdvances()
{
size_t runCount = m_complexTextRuns.size();
for (size_t r = 0; r < runCount; ++r) {
ComplexTextRun& complexTextRun = *m_complexTextRuns[r];
unsigned glyphCount = complexTextRun.glyphCount();
const SimpleFontData* fontData = complexTextRun.fontData();
const CGGlyph* glyphs = complexTextRun.glyphs();
const CGSize* advances = complexTextRun.advances();
bool lastRun = r + 1 == runCount;
const UChar* cp = complexTextRun.characters();
CGFloat roundedSpaceWidth = roundCGFloat(fontData->spaceWidth());
bool roundsAdvances = !m_font.isPrinterFont() && fontData->platformData().roundsGlyphAdvances();
bool hasExtraSpacing = (m_font.letterSpacing() || m_font.wordSpacing() || m_padding) && !m_run.spacingDisabled();
CFIndex lastCharacterIndex = m_run.ltr() ? numeric_limits<CFIndex>::min() : 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 = Font::treatAsSpace(ch);
CGGlyph glyph = treatAsSpace ? fontData->spaceGlyph() : glyphs[i];
CGSize advance = treatAsSpace ? CGSizeMake(fontData->spaceWidth(), advances[i].height) : advances[i];
if (ch == '\t' && m_run.allowTabs()) {
float tabWidth = m_font.tabWidth();
advance.width = tabWidth - fmodf(m_run.xPos() + m_totalWidth, tabWidth);
} else if (ch == zeroWidthSpace || Font::treatAsZeroWidthSpace(ch) && !treatAsSpace) {
advance.width = 0;
glyph = fontData->spaceGlyph();
}
float roundedAdvanceWidth = roundf(advance.width);
if (roundsAdvances)
advance.width = roundedAdvanceWidth;
advance.width += fontData->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 (roundedAdvanceWidth == roundedSpaceWidth && (fontData->pitch() == FixedPitch || glyph == fontData->spaceGlyph()) && m_run.applyWordRounding())
advance.width = fontData->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 && m_font.letterSpacing())
advance.width += m_font.letterSpacing();
// Handle justification and word-spacing.
if (glyph == fontData->spaceGlyph()) {
// Account for padding. WebCore uses space padding to justify text.
// We distribute the specified padding over the available spaces in the run.
if (m_padding) {
// Use leftover padding if not evenly divisible by number of spaces.
if (m_padding < m_padPerSpace) {
advance.width += m_padding;
m_padding = 0;
} else {
advance.width += m_padPerSpace;
m_padding -= m_padPerSpace;
}
}
// Account for word-spacing.
if (treatAsSpace && characterIndex > 0 && !Font::treatAsSpace(*m_run.data(characterIndex - 1)) && m_font.wordSpacing())
advance.width += m_font.wordSpacing();
}
}
// Deal with the float/integer impedance mismatch between CG and WebCore. "Words" (characters
// followed by a character defined by isRoundingHackCharacter()) are always an integer width.
// 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() && Font::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.
if (m_run.applyWordRounding() && !lastGlyph && Font::isRoundingHackCharacter(nextCh) || m_run.applyRunRounding() && lastGlyph) {
CGFloat totalWidth = m_totalWidth + advance.width;
CGFloat extraWidth = ceilCGFloat(totalWidth) - totalWidth;
if (m_run.ltr())
advance.width += extraWidth;
else {
m_totalWidth += extraWidth;
if (m_lastRoundingGlyph)
m_adjustedAdvances[m_lastRoundingGlyph - 1].width += extraWidth;
else
m_finalRoundingWidth = extraWidth;
m_lastRoundingGlyph = m_adjustedAdvances.size() + 1;
}
}
m_totalWidth += advance.width;
advance.height *= -1;
m_adjustedAdvances.append(advance);
m_adjustedGlyphs.append(glyph);
lastCharacterIndex = characterIndex;
}
if (!isMonotonic)
complexTextRun.setIsNonMonotonic();
}
}
} // namespace WebCore