Add function QGlyphRun::setRawData()

To provide an optimized way of constructing QGlyphRun objects with no
copying or allocation, we add function setRawData() (naming inspired by
QByteArray::setRawData()). Data retrieved from QRawFont can be passed
directly into this. The logic is now that the data pointers in
QGlyphRunPrivate should always point to the current valid data and is
what will be used in comparisons and drawing calls. The vectors are
optimizations to avoid unnecessary copying if the user wants to use
the QVector based API (which makes it easier to manage the memory.)
This reflected in the functions that return QVectors, which will
return the stored vector if and only if it is identical to the
current pointer. Otherwise we will have to copy the memory.

The internal addition operators in QGlyphRun have been removed since
they really provide no real optimization and have an unclear definition
if the two glyph runs are based on different fonts.

Reviewed-by: Jiang Jiang

2 files changed, 10 insertions, 7 deletions

diff --git a/src/gui/painting/qpainter.cpp b/src/gui/painting/qpainter.cpp
index d2b35c8..1bd9303 100644
--- a/src/gui/painting/qpainter.cpp
+++ b/src/gui/painting/qpainter.cpp
@@ -5801,10 +5801,12 @@ void QPainter::drawGlyphRun(const QPointF &position, const QGlyphRun &glyphRun)
     if (!font.isValid())
         return;
 
-    QVector<quint32> glyphIndexes = glyphRun.glyphIndexes();
-    QVector<QPointF> glyphPositions = glyphRun.positions();
+    QGlyphRunPrivate *glyphRun_d = QGlyphRunPrivate::get(glyphRun);
 
-    int count = qMin(glyphIndexes.size(), glyphPositions.size());
+    const quint32 *glyphIndexes = glyphRun_d->glyphIndexData;
+    const QPointF *glyphPositions = glyphRun_d->glyphPositionData;
+
+    int count = qMin(glyphRun_d->glyphIndexDataSize, glyphRun_d->glyphPositionDataSize);
     QVarLengthArray<QFixedPoint, 128> fixedPointPositions(count);
 
     QRawFontPrivate *fontD = QRawFontPrivate::get(font);
@@ -5818,17 +5820,18 @@ void QPainter::drawGlyphRun(const QPointF &position, const QGlyphRun &glyphRun)
     }
 
     for (int i=0; i<count; ++i) {
-        QPointF processedPosition = position + glyphPositions.at(i);
+        QPointF processedPosition = position + glyphPositions[i];
         if (!supportsTransformations)
             processedPosition = d->state->transform().map(processedPosition);
         fixedPointPositions[i] = QFixedPoint::fromPointF(processedPosition);
     }
 
-    d->drawGlyphs(glyphIndexes.data(), fixedPointPositions.data(), count, font, glyphRun.overline(),
+    d->drawGlyphs(glyphIndexes, fixedPointPositions.data(), count, font, glyphRun.overline(),
                   glyphRun.underline(), glyphRun.strikeOut());
 }
 
-void QPainterPrivate::drawGlyphs(quint32 *glyphArray, QFixedPoint *positions, int glyphCount,
+void QPainterPrivate::drawGlyphs(const quint32 *glyphArray, QFixedPoint *positions,
+                                 int glyphCount,
                                  const QRawFont &font, bool overline, bool underline,
                                  bool strikeOut)
 {
diff --git a/src/gui/painting/qpainter_p.h b/src/gui/painting/qpainter_p.h
index 35cdf86..79d4b4b 100644
--- a/src/gui/painting/qpainter_p.h
+++ b/src/gui/painting/qpainter_p.h
@@ -232,7 +232,7 @@ public:
     void drawOpaqueBackground(const QPainterPath &path, DrawOperation operation);
 
 #if !defined(QT_NO_RAWFONT)
-    void drawGlyphs(quint32 *glyphArray, QFixedPoint *positionArray, int glyphCount,
+    void drawGlyphs(const quint32 *glyphArray, QFixedPoint *positionArray, int glyphCount,
                     const QRawFont &font, bool overline = false, bool underline = false,
                     bool strikeOut = false);
 #endif