From 4e319ca4c47a99295c1a07aa759e09d86f1b7c87 Mon Sep 17 00:00:00 2001 From: Konstantin Ritt Date: Mon, 3 Feb 2014 02:44:46 +0200 Subject: Optimize stringToCMap() usage CMAP guarantees there is 1:1 mapping between the Unicode code points array and the glyph indexes array, which means the QString length always greater than or equal to a sufficient glyph indexes array length. Simply add some asserts and improve the memory consumption and the performance where possible. Change-Id: I0bc8cdba5f86c1c0ba9e79c8d5f96cbe56ec463e Reviewed-by: Lars Knoll --- src/gui/text/qfontmetrics.cpp | 161 ++++++++++++++++++++++++++++++------------ 1 file changed, 116 insertions(+), 45 deletions(-) (limited to 'src/gui/text/qfontmetrics.cpp') diff --git a/src/gui/text/qfontmetrics.cpp b/src/gui/text/qfontmetrics.cpp index 08105834ea..2f4709afe4 100644 --- a/src/gui/text/qfontmetrics.cpp +++ b/src/gui/text/qfontmetrics.cpp @@ -458,12 +458,19 @@ int QFontMetrics::leftBearing(QChar ch) const d->alterCharForCapitalization(ch); - QGlyphLayoutArray<10> glyphs; - int nglyphs = 9; - engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, QFontEngine::GlyphIndicesOnly); - // ### can nglyphs != 1 happen at all? Not currently I think + glyph_t glyph; + + QGlyphLayout glyphs; + glyphs.numGlyphs = 1; + glyphs.glyphs = &glyph; + + int nglyphs = 1; + if (!engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, QFontEngine::GlyphIndicesOnly)) + Q_UNREACHABLE(); + Q_ASSERT(nglyphs == 1); + qreal lb; - engine->getGlyphBearings(glyphs.glyphs[0], &lb); + engine->getGlyphBearings(glyph, &lb); return qRound(lb); } @@ -493,12 +500,19 @@ int QFontMetrics::rightBearing(QChar ch) const d->alterCharForCapitalization(ch); - QGlyphLayoutArray<10> glyphs; - int nglyphs = 9; - engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, QFontEngine::GlyphIndicesOnly); - // ### can nglyphs != 1 happen at all? Not currently I think + glyph_t glyph; + + QGlyphLayout glyphs; + glyphs.numGlyphs = 1; + glyphs.glyphs = &glyph; + + int nglyphs = 1; + if (!engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, QFontEngine::GlyphIndicesOnly)) + Q_UNREACHABLE(); + Q_ASSERT(nglyphs == 1); + qreal rb; - engine->getGlyphBearings(glyphs.glyphs[0], 0, &rb); + engine->getGlyphBearings(glyph, 0, &rb); return qRound(rb); } @@ -538,11 +552,8 @@ int QFontMetrics::width(const QString &text, int len, int flags) const int numGlyphs = len; QVarLengthGlyphLayoutArray glyphs(numGlyphs); QFontEngine *engine = d->engineForScript(QChar::Script_Common); - if (!engine->stringToCMap(text.data(), len, &glyphs, &numGlyphs, 0)) { - glyphs.resize(numGlyphs); - if (!engine->stringToCMap(text.data(), len, &glyphs, &numGlyphs, 0)) - Q_ASSERT_X(false, Q_FUNC_INFO, "stringToCMap shouldn't fail twice"); - } + if (!engine->stringToCMap(text.data(), len, &glyphs, &numGlyphs, 0)) + Q_UNREACHABLE(); QFixed width; for (int i = 0; i < numGlyphs; ++i) @@ -594,10 +605,20 @@ int QFontMetrics::width(QChar ch) const d->alterCharForCapitalization(ch); - QGlyphLayoutArray<8> glyphs; - int nglyphs = 7; - engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, 0); - return qRound(glyphs.advances[0]); + QFixed advance; + + QGlyphLayout glyphs; + glyphs.numGlyphs = 1; + glyph_t glyph; + glyphs.glyphs = &glyph; + glyphs.advances = &advance; + + int nglyphs = 1; + if (!engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, 0)) + Q_UNREACHABLE(); + Q_ASSERT(nglyphs == 1); + + return qRound(advance); } /*! \obsolete @@ -639,10 +660,20 @@ int QFontMetrics::charWidth(const QString &text, int pos) const d->alterCharForCapitalization(ch); - QGlyphLayoutArray<8> glyphs; - int nglyphs = 7; - engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, 0); - width = qRound(glyphs.advances[0]); + QFixed advance; + + QGlyphLayout glyphs; + glyphs.numGlyphs = 1; + glyph_t glyph; + glyphs.glyphs = &glyph; + glyphs.advances = &advance; + + int nglyphs = 1; + if (!engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, 0)) + Q_UNREACHABLE(); + Q_ASSERT(nglyphs == 1); + + width = qRound(advance); } return width; } @@ -708,10 +739,18 @@ QRect QFontMetrics::boundingRect(QChar ch) const d->alterCharForCapitalization(ch); - QGlyphLayoutArray<10> glyphs; - int nglyphs = 9; - engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, QFontEngine::GlyphIndicesOnly); - glyph_metrics_t gm = engine->boundingBox(glyphs.glyphs[0]); + glyph_t glyph; + + QGlyphLayout glyphs; + glyphs.numGlyphs = 1; + glyphs.glyphs = &glyph; + + int nglyphs = 1; + if (!engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, QFontEngine::GlyphIndicesOnly)) + Q_UNREACHABLE(); + Q_ASSERT(nglyphs == 1); + + glyph_metrics_t gm = engine->boundingBox(glyph); return QRect(qRound(gm.x), qRound(gm.y), qRound(gm.width), qRound(gm.height)); } @@ -1326,12 +1365,19 @@ qreal QFontMetricsF::leftBearing(QChar ch) const d->alterCharForCapitalization(ch); - QGlyphLayoutArray<10> glyphs; - int nglyphs = 9; - engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, QFontEngine::GlyphIndicesOnly); - // ### can nglyphs != 1 happen at all? Not currently I think + glyph_t glyph; + + QGlyphLayout glyphs; + glyphs.numGlyphs = 1; + glyphs.glyphs = &glyph; + + int nglyphs = 1; + if (!engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, QFontEngine::GlyphIndicesOnly)) + Q_UNREACHABLE(); + Q_ASSERT(nglyphs == 1); + qreal lb; - engine->getGlyphBearings(glyphs.glyphs[0], &lb); + engine->getGlyphBearings(glyph, &lb); return lb; } @@ -1361,12 +1407,19 @@ qreal QFontMetricsF::rightBearing(QChar ch) const d->alterCharForCapitalization(ch); - QGlyphLayoutArray<10> glyphs; - int nglyphs = 9; - engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, QFontEngine::GlyphIndicesOnly); - // ### can nglyphs != 1 happen at all? Not currently I think + glyph_t glyph; + + QGlyphLayout glyphs; + glyphs.numGlyphs = 1; + glyphs.glyphs = &glyph; + + int nglyphs = 1; + if (!engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, QFontEngine::GlyphIndicesOnly)) + Q_UNREACHABLE(); + Q_ASSERT(nglyphs == 1); + qreal rb; - engine->getGlyphBearings(glyphs.glyphs[0], 0, &rb); + engine->getGlyphBearings(glyph, 0, &rb); return rb; } @@ -1431,10 +1484,20 @@ qreal QFontMetricsF::width(QChar ch) const d->alterCharForCapitalization(ch); - QGlyphLayoutArray<8> glyphs; - int nglyphs = 7; - engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, 0); - return glyphs.advances[0].toReal(); + QFixed advance; + + QGlyphLayout glyphs; + glyphs.numGlyphs = 1; + glyph_t glyph; + glyphs.glyphs = &glyph; + glyphs.advances = &advance; + + int nglyphs = 1; + if (!engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, 0)) + Q_UNREACHABLE(); + Q_ASSERT(nglyphs == 1); + + return advance.toReal(); } /*! @@ -1496,10 +1559,18 @@ QRectF QFontMetricsF::boundingRect(QChar ch) const d->alterCharForCapitalization(ch); - QGlyphLayoutArray<10> glyphs; - int nglyphs = 9; - engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, QFontEngine::GlyphIndicesOnly); - glyph_metrics_t gm = engine->boundingBox(glyphs.glyphs[0]); + glyph_t glyph; + + QGlyphLayout glyphs; + glyphs.numGlyphs = 1; + glyphs.glyphs = &glyph; + + int nglyphs = 1; + if (!engine->stringToCMap(&ch, 1, &glyphs, &nglyphs, QFontEngine::GlyphIndicesOnly)) + Q_UNREACHABLE(); + Q_ASSERT(nglyphs == 1); + + glyph_metrics_t gm = engine->boundingBox(glyph); return QRectF(gm.x.toReal(), gm.y.toReal(), gm.width.toReal(), gm.height.toReal()); } -- cgit v1.2.3