void GraphicsContext::drawBidiText(const Font& font, const TextRun& run, const FloatPoint& point)
{
if (paintingDisabled())
return;
BidiResolver<TextRunIterator, BidiCharacterRun> bidiResolver;
WTF::Unicode::Direction paragraphDirection = run.ltr() ? WTF::Unicode::LeftToRight : WTF::Unicode::RightToLeft;
bidiResolver.setStatus(BidiStatus(paragraphDirection, paragraphDirection, paragraphDirection, new BidiContext(run.ltr() ? 0 : 1, paragraphDirection, run.directionalOverride())));
bidiResolver.setPosition(TextRunIterator(&run, 0));
bidiResolver.createBidiRunsForLine(TextRunIterator(&run, run.length()));
if (!bidiResolver.runCount())
return;
FloatPoint currPoint = point;
BidiCharacterRun* bidiRun = bidiResolver.firstRun();
while (bidiRun) {
TextRun subrun = run;
subrun.setText(run.data(bidiRun->start()), bidiRun->stop() - bidiRun->start());
subrun.setRTL(bidiRun->level() % 2);
subrun.setDirectionalOverride(bidiRun->dirOverride(false));
font.drawText(this, subrun, currPoint);
bidiRun = bidiRun->next();
// FIXME: Have Font::drawText return the width of what it drew so that we don't have to re-measure here.
if (bidiRun)
currPoint.move(font.floatWidth(subrun), 0.f);
}
bidiResolver.deleteRuns();
}
void GraphicsContext::drawBidiText(const Font& font, const TextRun& run, const FloatPoint& point)
{
if (paintingDisabled())
return;
BidiResolver<TextRunIterator, BidiCharacterRun> bidiResolver;
bidiResolver.setStatus(BidiStatus(run.direction(), run.directionalOverride()));
bidiResolver.setPosition(TextRunIterator(&run, 0));
// FIXME: This ownership should be reversed. We should pass BidiRunList
// to BidiResolver in createBidiRunsForLine.
BidiRunList<BidiCharacterRun>& bidiRuns = bidiResolver.runs();
bidiResolver.createBidiRunsForLine(TextRunIterator(&run, run.length()));
if (!bidiRuns.runCount())
return;
FloatPoint currPoint = point;
BidiCharacterRun* bidiRun = bidiRuns.firstRun();
while (bidiRun) {
TextRun subrun = run;
subrun.setText(run.data(bidiRun->start()), bidiRun->stop() - bidiRun->start());
bool isRTL = bidiRun->level() % 2;
subrun.setDirection(isRTL ? RTL : LTR);
subrun.setDirectionalOverride(bidiRun->dirOverride(false));
font.drawText(this, subrun, currPoint);
bidiRun = bidiRun->next();
// FIXME: Have Font::drawText return the width of what it drew so that we don't have to re-measure here.
if (bidiRun)
currPoint.move(font.width(subrun), 0);
}
bidiRuns.deleteRuns();
}
// ReverseBidi is a trimmed-down version of GraphicsContext::drawBidiText()
void ReverseBidi(UChar* chars, int len) {
using namespace WTF::Unicode;
WTF::Vector<UChar> result;
result.reserveCapacity(len);
TextRun run(chars, len);
BidiResolver<TextRunIterator, BidiCharacterRun> bidiResolver;
BidiRunList<BidiCharacterRun>& bidiRuns = bidiResolver.runs();
bidiResolver.setStatus(BidiStatus(LeftToRight, LeftToRight, LeftToRight,
BidiContext::create(0, LeftToRight, false)));
bidiResolver.setPosition(TextRunIterator(&run, 0));
bidiResolver.createBidiRunsForLine(TextRunIterator(&run, len));
if (!bidiRuns.runCount())
return;
BidiCharacterRun* bidiRun = bidiRuns.firstRun();
while (bidiRun) {
int bidiStart = bidiRun->start();
int bidiStop = bidiRun->stop();
int size = result.size();
int bidiCount = bidiStop - bidiStart;
result.append(chars + bidiStart, bidiCount);
if (bidiRun->level() % 2) {
UChar* start = &result[size];
UChar* end = start + bidiCount;
// reverse the order of any RTL substrings
while (start < end) {
UChar temp = *start;
*start++ = *--end;
*end = temp;
}
start = &result[size];
end = start + bidiCount - 1;
// if the RTL substring had a surrogate pair, restore its order
while (start < end) {
UChar trail = *start++;
if (!U16_IS_SURROGATE(trail))
continue;
start[-1] = *start; // lead
*start++ = trail;
}
}
bidiRun = bidiRun->next();
}
bidiRuns.deleteRuns();
memcpy(chars, &result[0], len * sizeof(UChar));
}