void HarfBuzzShaper::fillGlyphBufferFromHarfBuzzRun(GlyphBuffer* glyphBuffer, HarfBuzzRun* currentRun, FloatPoint& firstOffsetOfNextRun)
{
FloatPoint* offsets = currentRun->offsets();
uint16_t* glyphs = currentRun->glyphs();
float* advances = currentRun->advances();
unsigned numGlyphs = currentRun->numGlyphs();
uint16_t* glyphToCharacterIndexes = currentRun->glyphToCharacterIndexes();
for (unsigned i = 0; i < numGlyphs; ++i) {
uint16_t currentCharacterIndex = currentRun->startIndex() + glyphToCharacterIndexes[i];
FloatPoint& currentOffset = offsets[i];
FloatPoint& nextOffset = (i == numGlyphs - 1) ? firstOffsetOfNextRun : offsets[i + 1];
float glyphAdvanceX = advances[i] + nextOffset.x() - currentOffset.x();
float glyphAdvanceY = nextOffset.y() - currentOffset.y();
if (m_run.rtl()) {
if (currentCharacterIndex > m_toIndex)
m_startOffset.move(glyphAdvanceX, glyphAdvanceY);
else if (currentCharacterIndex >= m_fromIndex)
glyphBuffer->add(glyphs[i], currentRun->fontData(), createGlyphBufferAdvance(glyphAdvanceX, glyphAdvanceY));
} else {
if (currentCharacterIndex < m_fromIndex)
m_startOffset.move(glyphAdvanceX, glyphAdvanceY);
else if (currentCharacterIndex < m_toIndex)
glyphBuffer->add(glyphs[i], currentRun->fontData(), createGlyphBufferAdvance(glyphAdvanceX, glyphAdvanceY));
}
}
}
void HarfBuzzShaper::setGlyphPositionsForHarfBuzzRun(GlyphBuffer* glyphBuffer)
{
hb_glyph_info_t* glyphInfos = hb_buffer_get_glyph_infos(m_harfbuzzBuffer, 0);
hb_glyph_position_t* glyphPositions = hb_buffer_get_glyph_positions(m_harfbuzzBuffer, 0);
HarfBuzzRun* currentRun = m_harfbuzzRuns.last().get();
unsigned numGlyphs = currentRun->numGlyphs();
float totalAdvance = 0;
float nextOffsetX = harfbuzzPositionToFloat(glyphPositions[0].x_offset);
float nextOffsetY = -harfbuzzPositionToFloat(glyphPositions[0].y_offset);
// HarfBuzz returns the shaping result in visual order. We need not to flip them for RTL.
for (size_t i = 0; i < numGlyphs; ++i) {
bool runEnd = i + 1 == numGlyphs;
uint16_t glyph = glyphInfos[i].codepoint;
float offsetX = nextOffsetX;
float offsetY = nextOffsetY;
float advance = harfbuzzPositionToFloat(glyphPositions[i].x_advance);
nextOffsetX = runEnd ? 0 : harfbuzzPositionToFloat(glyphPositions[i + 1].x_offset);
nextOffsetY = runEnd ? 0 : -harfbuzzPositionToFloat(glyphPositions[i + 1].y_offset);
unsigned currentCharacterIndex = m_startIndexOfCurrentRun + glyphInfos[i].cluster;
bool isClusterEnd = runEnd || glyphInfos[i].cluster != glyphInfos[i + 1].cluster;
float spacing = isClusterEnd ? m_letterSpacing : 0;
if (isClusterEnd && isWordEnd(currentCharacterIndex))
spacing += determineWordBreakSpacing();
if (m_currentFontData->isZeroWidthSpaceGlyph(glyph)) {
currentRun->setGlyphAndPositions(i, glyph, 0, 0, 0);
if (glyphBuffer)
glyphBuffer->add(glyph, m_currentFontData, createGlyphBufferAdvance(0, 0));
continue;
}
advance += spacing;
currentRun->setGlyphAndPositions(i, glyph, totalAdvance + offsetX, offsetY, advance);
if (glyphBuffer) {
float glyphAdvanceX = advance + nextOffsetX - offsetX;
float glyphAdvanceY = nextOffsetY - offsetY;
glyphBuffer->add(glyph, m_currentFontData, createGlyphBufferAdvance(glyphAdvanceX, glyphAdvanceY));
}
totalAdvance += advance;
}
currentRun->setWidth(totalAdvance > 0.0 ? totalAdvance : 0.0);
m_totalWidth += currentRun->width();
}
