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Minor optimization for QTextEngine::shapeText()

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Remember the engine index for each sub-item and avoid moveGlyphData()
where possible (ie. when there are no glyph indexes to care about).
Also don't memmove data we didn't ever initialize.

Change-Id: Ib8e5fd937a10e4e3c8c0e18961a2e2c1a4167924
Reviewed-by: Ahmed Saidi <justroftest@gmail.com>
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
This commit is contained in:
Konstantin Ritt 2014-02-09 06:37:51 +02:00 committed by The Qt Project
parent c77222c0e7
commit bbdea065aa
1 changed files with 36 additions and 43 deletions
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79
src/gui/text/qtextengine.cpp
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@ -918,12 +918,9 @@ void QTextEngine::shapeText(int item) const
QFontEngine *fontEngine = this->fontEngine(si, &si.ascent, &si.descent, &si.leading);
// split up the item into parts that come from different font engines
// k * 3 entries, array[k] == index in string, array[k + 1] == index in glyphs, array[k + 2] == engine index
QVector<uint> itemBoundaries;
itemBoundaries.reserve(16);
// k * 2 entries, array[k] == index in string, array[k + 1] == index in glyphs
itemBoundaries.append(0);
itemBoundaries.append(0);
itemBoundaries.reserve(24);
if (fontEngine->type() == QFontEngine::Multi) {
// ask the font engine to find out which glyphs (as an index in the specific font)
// to use for the text in one item.
@ -947,22 +944,31 @@ void QTextEngine::shapeText(int item) const
}
}
uint lastEngine = 0;
uint lastEngine = ~0u;
for (int i = 0, glyph_pos = 0; i < itemLength; ++i, ++glyph_pos) {
const uint engineIdx = initialGlyphs.glyphs[glyph_pos] >> 24;
if (lastEngine != engineIdx && glyph_pos > 0) {
if (lastEngine != engineIdx) {
itemBoundaries.append(i);
itemBoundaries.append(glyph_pos);
itemBoundaries.append(engineIdx);
QFontEngine *actualFontEngine = static_cast<QFontEngineMulti *>(fontEngine)->engine(engineIdx);
si.ascent = qMax(actualFontEngine->ascent(), si.ascent);
si.descent = qMax(actualFontEngine->descent(), si.descent);
si.leading = qMax(actualFontEngine->leading(), si.leading);
if (engineIdx != 0) {
QFontEngine *actualFontEngine = static_cast<QFontEngineMulti *>(fontEngine)->engine(engineIdx);
si.ascent = qMax(actualFontEngine->ascent(), si.ascent);
si.descent = qMax(actualFontEngine->descent(), si.descent);
si.leading = qMax(actualFontEngine->leading(), si.leading);
}
lastEngine = engineIdx;
}
lastEngine = engineIdx;
if (QChar::isHighSurrogate(string[i]) && i + 1 < itemLength && QChar::isLowSurrogate(string[i + 1]))
++i;
}
} else {
itemBoundaries.append(0);
itemBoundaries.append(0);
itemBoundaries.append(0);
}
bool kerningEnabled;
@ -1039,16 +1045,6 @@ void QTextEngine::shapeText(int item) const
si.width += glyphs.advances_x[i] * !glyphs.attributes[i].dontPrint;
}
static inline void moveGlyphData(const QGlyphLayout &destination, const QGlyphLayout &source, int num)
{
if (num > 0 && destination.glyphs != source.glyphs) {
memmove(destination.glyphs, source.glyphs, num * sizeof(glyph_t));
memmove(destination.attributes, source.attributes, num * sizeof(QGlyphAttributes));
memmove(destination.advances_x, source.advances_x, num * sizeof(QFixed));
memmove(destination.offsets, source.offsets, num * sizeof(QFixedPoint));
}
}
#ifdef QT_ENABLE_HARFBUZZ_NG
QT_BEGIN_INCLUDE_NAMESPACE
@ -1075,20 +1071,15 @@ int QTextEngine::shapeTextWithHarfbuzzNG(const QScriptItem &si, const ushort *st
uint glyphs_shaped = 0;
int remaining_glyphs = itemLength;
for (int k = 0; k < itemBoundaries.size(); k += 2) { // for the +2, see the comment at the definition of itemBoundaries
for (int k = 0; k < itemBoundaries.size(); k += 3) {
uint item_pos = itemBoundaries[k];
uint item_length = itemLength;
uint item_length = (k + 4 < itemBoundaries.size() ? itemBoundaries[k + 3] : itemLength) - item_pos;
uint item_glyph_pos = itemBoundaries[k + 1];
if (k + 3 < itemBoundaries.size())
item_length = itemBoundaries[k + 2];
item_length -= item_pos;
uint engineIdx = itemBoundaries[k + 2];
QFontEngine *actualFontEngine = fontEngine;
uint engineIdx = 0;
if (fontEngine->type() == QFontEngine::Multi) {
engineIdx = availableGlyphs(&si).glyphs[glyphs_shaped] >> 24;
if (fontEngine->type() == QFontEngine::Multi)
actualFontEngine = static_cast<QFontEngineMulti *>(fontEngine)->engine(engineIdx);
}
// prepare buffer
@ -1138,8 +1129,6 @@ int QTextEngine::shapeTextWithHarfbuzzNG(const QScriptItem &si, const ushort *st
// fetch the shaped glyphs and metrics
QGlyphLayout g = availableGlyphs(&si).mid(glyphs_shaped, num_glyphs);
if (num_glyphs != item_glyph_pos)
moveGlyphData(g.mid(num_glyphs), g.mid(item_glyph_pos), remaining_glyphs);
ushort *log_clusters = logClusters(&si) + item_pos;
hb_glyph_info_t *infos = hb_buffer_get_glyph_infos(buffer, 0);
@ -1196,6 +1185,12 @@ Q_STATIC_ASSERT(sizeof(HB_GlyphAttributes) == sizeof(QGlyphAttributes));
Q_STATIC_ASSERT(sizeof(HB_Fixed) == sizeof(QFixed));
Q_STATIC_ASSERT(sizeof(HB_FixedPoint) == sizeof(QFixedPoint));
static inline void moveGlyphData(const QGlyphLayout &destination, const QGlyphLayout &source, int num)
{
if (num > 0 && destination.glyphs != source.glyphs)
memmove(destination.glyphs, source.glyphs, num * sizeof(glyph_t));
}
int QTextEngine::shapeTextWithHarfbuzz(const QScriptItem &si, const ushort *string, int itemLength, QFontEngine *fontEngine, const QVector<uint> &itemBoundaries, bool kerningEnabled) const
{
HB_ShaperItem entire_shaper_item;
@ -1224,14 +1219,12 @@ int QTextEngine::shapeTextWithHarfbuzz(const QScriptItem &si, const ushort *stri
int remaining_glyphs = entire_shaper_item.num_glyphs;
int glyph_pos = 0;
// for each item shape using harfbuzz and store the results in our layoutData's glyphs array.
for (int k = 0; k < itemBoundaries.size(); k += 2) { // for the +2, see the comment at the definition of itemBoundaries
for (int k = 0; k < itemBoundaries.size(); k += 3) {
HB_ShaperItem shaper_item = entire_shaper_item;
shaper_item.item.pos = itemBoundaries[k];
if (k < itemBoundaries.size() - 3) {
shaper_item.item.length = itemBoundaries[k + 2] - shaper_item.item.pos;
shaper_item.num_glyphs = itemBoundaries[k + 3] - itemBoundaries[k + 1];
if (k + 4 < itemBoundaries.size()) {
shaper_item.item.length = itemBoundaries[k + 3] - shaper_item.item.pos;
shaper_item.num_glyphs = itemBoundaries[k + 4] - itemBoundaries[k + 1];
} else { // last combo in the list, avoid out of bounds access.
shaper_item.item.length -= shaper_item.item.pos - entire_shaper_item.item.pos;
shaper_item.num_glyphs -= itemBoundaries[k + 1];
@ -1240,10 +1233,9 @@ int QTextEngine::shapeTextWithHarfbuzz(const QScriptItem &si, const ushort *stri
if (shaper_item.num_glyphs < shaper_item.item.length)
shaper_item.num_glyphs = shaper_item.item.length;
uint engineIdx = itemBoundaries[k + 2];
QFontEngine *actualFontEngine = fontEngine;
uint engineIdx = 0;
if (fontEngine->type() == QFontEngine::Multi) {
engineIdx = uint(availableGlyphs(&si).glyphs[glyph_pos] >> 24);
actualFontEngine = static_cast<QFontEngineMulti *>(fontEngine)->engine(engineIdx);
shaper_item.glyphIndicesPresent = true;
@ -1259,7 +1251,7 @@ int QTextEngine::shapeTextWithHarfbuzz(const QScriptItem &si, const ushort *stri
return 0;
const QGlyphLayout g = availableGlyphs(&si).mid(glyph_pos);
if (shaper_item.num_glyphs > shaper_item.item.length)
if (fontEngine->type() == QFontEngine::Multi && shaper_item.num_glyphs > shaper_item.item.length)
moveGlyphData(g.mid(shaper_item.num_glyphs), g.mid(shaper_item.initialGlyphCount), remaining_glyphs);
shaper_item.glyphs = reinterpret_cast<HB_Glyph *>(g.glyphs);
@ -1276,7 +1268,8 @@ int QTextEngine::shapeTextWithHarfbuzz(const QScriptItem &si, const ushort *stri
} while (!qShapeItem(&shaper_item)); // this does the actual shaping via harfbuzz.
QGlyphLayout g = availableGlyphs(&si).mid(glyph_pos, shaper_item.num_glyphs);
moveGlyphData(g.mid(shaper_item.num_glyphs), g.mid(shaper_item.initialGlyphCount), remaining_glyphs);
if (fontEngine->type() == QFontEngine::Multi)
moveGlyphData(g.mid(shaper_item.num_glyphs), g.mid(shaper_item.initialGlyphCount), remaining_glyphs);
for (quint32 i = 0; i < shaper_item.item.length; ++i)
shaper_item.log_clusters[i] += glyph_pos;