// Advance to the next script run, returning false when the end of the
// TextRun has been reached.
bool ComplexTextController::nextScriptRun()
{
// Ensure we're not pointing at the small caps buffer.
m_item.string = m_run.characters();
if (!hb_utf16_script_run_next(0, &m_item.item, m_run.characters(), m_run.length(), &m_indexOfNextScriptRun))
return false;
// It is actually wrong to consider script runs at all in this code.
// Other WebKit code (e.g. Mac) segments complex text just by finding
// the longest span of text covered by a single font.
// But we currently need to call hb_utf16_script_run_next anyway to fill
// in the harfbuzz data structures to e.g. pick the correct script's shaper.
// So we allow that to run first, then do a second pass over the range it
// found and take the largest subregion that stays within a single font.
m_currentFontData = m_font->glyphDataForCharacter(m_item.string[m_item.item.pos], false).fontData;
unsigned endOfRun;
for (endOfRun = 1; endOfRun < m_item.item.length; ++endOfRun) {
const SimpleFontData* nextFontData = m_font->glyphDataForCharacter(m_item.string[m_item.item.pos + endOfRun], false).fontData;
if (nextFontData != m_currentFontData)
break;
}
m_item.item.length = endOfRun;
m_indexOfNextScriptRun = m_item.item.pos + endOfRun;
setupFontForScriptRun();
shapeGlyphs();
setGlyphXPositions(rtl());
return true;
}
// Advance to the next script run, returning false when the end of the
// TextRun has been reached.
bool nextScriptRun()
{
if (m_iterateBackwards) {
// In right-to-left mode we need to render the shaped glyph backwards and
// also render the script runs themselves backwards. So given a TextRun:
// AAAAAAACTTTTTTT (A = Arabic, C = Common, T = Thai)
// we render:
// TTTTTTCAAAAAAA
// (and the glyphs in each A, C and T section are backwards too)
if (!hb_utf16_script_run_prev(&m_numCodePoints, &m_item.item, m_run.characters(), m_run.length(), &m_indexOfNextScriptRun))
return false;
} else {
if (!hb_utf16_script_run_next(&m_numCodePoints, &m_item.item, m_run.characters(), m_run.length(), &m_indexOfNextScriptRun))
return false;
// It is actually wrong to consider script runs at all in this code.
// Other WebKit code (e.g. Mac) segments complex text just by finding
// the longest span of text covered by a single font.
// But we currently need to call hb_utf16_script_run_next anyway to fill
// in the harfbuzz data structures to e.g. pick the correct script's shaper.
// So we allow that to run first, then do a second pass over the range it
// found and take the largest subregion that stays within a single font.
const FontData* glyphData = m_font->glyphDataForCharacter(m_item.string[m_item.item.pos], false, false).fontData;
int endOfRun;
for (endOfRun = 1; endOfRun < m_item.item.length; ++endOfRun) {
const FontData* nextGlyphData = m_font->glyphDataForCharacter(m_item.string[m_item.item.pos + endOfRun], false, false).fontData;
if (nextGlyphData != glyphData)
break;
}
m_item.item.length = endOfRun;
m_indexOfNextScriptRun = m_item.item.pos + endOfRun;
}
setupFontForScriptRun();
shapeGlyphs();
setGlyphXPositions(rtl());
return true;
}
// Advance to the next script run, returning false when the end of the
// TextRun has been reached.
bool nextScriptRun()
{
if (m_iterateBackwards) {
// In right-to-left mode we need to render the shaped glyph backwards and
// also render the script runs themselves backwards. So given a TextRun:
// AAAAAAACTTTTTTT (A = Arabic, C = Common, T = Thai)
// we render:
// TTTTTTCAAAAAAA
// (and the glyphs in each A, C and T section are backwards too)
if (!hb_utf16_script_run_prev(&m_numCodePoints, &m_item.item, m_run.characters(), m_run.length(), &m_indexOfNextScriptRun))
return false;
} else {
if (!hb_utf16_script_run_next(&m_numCodePoints, &m_item.item, m_run.characters(), m_run.length(), &m_indexOfNextScriptRun))
return false;
}
setupFontForScriptRun();
if (!shapeGlyphs())
return false;
setGlyphXPositions(rtl());
return true;
}
// Advance to the next script run, returning false when the end of the
// TextRun has been reached.
bool ComplexTextController::nextScriptRun()
{
// Ensure we're not pointing at the small caps buffer.
m_item.string = m_run.characters();
if (!hb_utf16_script_run_next(0, &m_item.item, m_run.characters(), m_run.length(), &m_indexOfNextScriptRun))
return false;
// It is actually wrong to consider script runs at all in this code.
// Other WebKit code (e.g. Mac) segments complex text just by finding
// the longest span of text covered by a single font.
// But we currently need to call hb_utf16_script_run_next anyway to fill
// in the harfbuzz data structures to e.g. pick the correct script's shaper.
// So we allow that to run first, then do a second pass over the range it
// found and take the largest subregion that stays within a single font.
SurrogatePairAwareTextIterator iterator(static_cast<const UChar*>(&m_item.string[m_item.item.pos]), 0, static_cast<int>(m_item.item.length), static_cast<int>(m_item.item.length));
UChar32 character;
unsigned clusterLength = 0;
if (!iterator.consume(character, clusterLength))
return false;
m_currentFontData = m_font->glyphDataForCharacter(character, false).fontData;
iterator.advance(clusterLength);
while (iterator.consume(character, clusterLength)) {
const SimpleFontData* nextFontData = m_font->glyphDataForCharacter(character, false).fontData;
if (nextFontData != m_currentFontData)
break;
iterator.advance(clusterLength);
}
m_item.item.length = iterator.currentCharacter();
m_indexOfNextScriptRun = m_item.item.pos + iterator.currentCharacter();
setupFontForScriptRun();
shapeGlyphs();
setGlyphPositions(rtl());
return true;
}
