Long live QRawFont!

The QGlyphs API was initially attempted with a bastardization of
QFont which was meant to encapsulate a single, physical font
instance (a QFontEngine) where a set of glyph indexes would make
sense. This is not how QFont was intended to be used, and it caused
several issues. At the same time, the requirement for loading a
font from ttf/otf data and be able to access it and use it without
polluting the rest of the process with the font arose. To support
these two APIs we introduce QRawFont, which is an abstraction on
top of a single physical font.

Done-with: Jiang Jiang

4 files changed, 46 insertions, 43 deletions

diff --git a/src/gui/painting/qpaintbuffer.cpp b/src/gui/painting/qpaintbuffer.cpp
index dd4b3db..7870def 100644
--- a/src/gui/painting/qpaintbuffer.cpp
+++ b/src/gui/painting/qpaintbuffer.cpp
@@ -47,6 +47,7 @@
 #include <private/qimage_p.h>
 #include <qstatictext.h>
 #include <private/qstatictext_p.h>
+#include <private/qrawfont_p.h>
 
 #include <QDebug>
 
@@ -1754,26 +1755,38 @@ void QPainterReplayer::process(const QPaintBufferCommand &cmd)
         painter->setClipRegion(region, Qt::ClipOperation(cmd.extra));
         break; }
         
+#if !defined(QT_NO_RAWFONT)
     case QPaintBufferPrivate::Cmd_DrawStaticText: {
             
             QVariantList variants(d->variants.at(cmd.offset).value<QVariantList>());
             
             QFont font = variants.at(0).value<QFont>();
 
-            QVector<quint32> glyphs;
+            QVector<quint32> glyphIndexes;
             QVector<QPointF> positions;
 
             for (int i=0; i<(variants.size() - 1) / 2; ++i) {
-                glyphs.append(variants.at(i*2 + 1).toUInt());
+                glyphIndexes.append(variants.at(i*2 + 1).toUInt());
                 positions.append(variants.at(i*2 + 2).toPointF());
             }
 
             painter->setFont(font);
 
-            qt_draw_glyphs(painter, glyphs.constData(), positions.constData(), glyphs.size());
-            
-        break;
+            QRawFont rawFont;
+            QRawFontPrivate *rawFontD = QRawFontPrivate::get(rawFont);
+            QFontPrivate *fontD = QFontPrivate::get(font);
+            rawFontD->fontEngine = fontD->engineForScript(QUnicodeTables::Common);
+            rawFontD->fontEngine->ref.ref();
+
+            QGlyphs glyphs;
+            glyphs.setFont(rawFont);
+            glyphs.setGlyphIndexes(glyphIndexes);
+            glyphs.setPositions(positions);
+
+            painter->drawGlyphs(QPointF(), glyphs);
+            break;
     }
+#endif
 
     case QPaintBufferPrivate::Cmd_DrawText: {
         QPointF pos(d->floats.at(cmd.extra), d->floats.at(cmd.extra+1));
diff --git a/src/gui/painting/qpainter.cpp b/src/gui/painting/qpainter.cpp
index 50d65e6..bef6b7d 100644
--- a/src/gui/painting/qpainter.cpp
+++ b/src/gui/painting/qpainter.cpp
@@ -75,6 +75,7 @@
 #include <private/qstatictext_p.h>
 #include <private/qglyphs_p.h>
 #include <private/qstylehelper_p.h>
+#include <private/qrawfont_p.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -5790,12 +5791,14 @@ void QPainter::drawImage(const QRectF &targetRect, const QImage &image, const QR
 
     \sa QGlyphs::setFont(), QGlyphs::setPositions(), QGlyphs::setGlyphIndexes()
 */
+#if !defined(QT_NO_RAWFONT)
 void QPainter::drawGlyphs(const QPointF &position, const QGlyphs &glyphs)
 {
     Q_D(QPainter);
 
-    QFont oldFont = d->state->font;
-    d->state->font = glyphs.font();
+    QRawFont font = glyphs.font();
+    if (!font.isValid())
+        return;
 
     QVector<quint32> glyphIndexes = glyphs.glyphIndexes();
     QVector<QPointF> glyphPositions = glyphs.positions();
@@ -5814,39 +5817,20 @@ void QPainter::drawGlyphs(const QPointF &position, const QGlyphs &glyphs)
         fixedPointPositions[i] = QFixedPoint::fromPointF(processedPosition);
     }
 
-    d->drawGlyphs(glyphIndexes.data(), fixedPointPositions.data(), count);
-
-    d->state->font = oldFont;
+    d->drawGlyphs(glyphIndexes.data(), fixedPointPositions.data(), count, font, glyphs.overline(),
+                  glyphs.underline(), glyphs.strikeOut());
 }
 
-void qt_draw_glyphs(QPainter *painter, const quint32 *glyphArray, const QPointF *positionArray,
-                    int glyphCount)
-{
-    QVarLengthArray<QFixedPoint, 128> positions(glyphCount);
-    for (int i=0; i<glyphCount; ++i)
-        positions[i] = QFixedPoint::fromPointF(positionArray[i]);
-
-    QPainterPrivate *painter_d = QPainterPrivate::get(painter);
-    painter_d->drawGlyphs(const_cast<quint32 *>(glyphArray), positions.data(), glyphCount);
-}
-
-void QPainterPrivate::drawGlyphs(quint32 *glyphArray, QFixedPoint *positions, int glyphCount)
+void QPainterPrivate::drawGlyphs(quint32 *glyphArray, QFixedPoint *positions, int glyphCount,
+                                 const QRawFont &font, bool overline, bool underline,
+                                 bool strikeOut)
 {
     Q_Q(QPainter);
 
     updateState(state);
 
-    QFontEngine *fontEngine = state->font.d->engineForScript(QUnicodeTables::Common);
-
-    while (fontEngine->type() == QFontEngine::Multi) {
-        // Pick engine based on first glyph in array if we are using a multi engine.
-        // (all glyphs must be for same font)
-        int engineIdx = 0;
-        if (glyphCount > 0)
-            engineIdx = glyphArray[0] >> 24;
-
-        fontEngine = static_cast<QFontEngineMulti *>(fontEngine)->engine(engineIdx);
-    }
+    QRawFontPrivate *fontD = QRawFontPrivate::get(font);
+    QFontEngine *fontEngine = fontD->fontEngine;
 
     QFixed leftMost;
     QFixed rightMost;
@@ -5881,7 +5865,6 @@ void QPainterPrivate::drawGlyphs(quint32 *glyphArray, QFixedPoint *positions, in
         extended->drawStaticTextItem(&staticTextItem);
     } else {
         QTextItemInt textItem;
-        textItem.f = &state->font;
         textItem.fontEngine = fontEngine;
 
         QVarLengthArray<QFixed, 128> advances(glyphCount);
@@ -5903,20 +5886,21 @@ void QPainterPrivate::drawGlyphs(quint32 *glyphArray, QFixedPoint *positions, in
     }
 
     QTextItemInt::RenderFlags flags;
-    if (state->font.underline())
+    if (underline)
         flags |= QTextItemInt::Underline;
-    if (state->font.overline())
+    if (overline)
         flags |= QTextItemInt::Overline;
-    if (state->font.strikeOut())
+    if (strikeOut)
         flags |= QTextItemInt::StrikeOut;
 
     drawTextItemDecoration(q, QPointF(leftMost.toReal(), baseLine.toReal()),
                            fontEngine,
-                           (state->font.underline()
-                                ? QTextCharFormat::SingleUnderline
-                                : QTextCharFormat::NoUnderline),
+                           (underline
+                              ? QTextCharFormat::SingleUnderline
+                              : QTextCharFormat::NoUnderline),
                            flags, width.toReal(), QTextCharFormat());
 }
+#endif // QT_NO_RAWFONT
 
 /*!
 
diff --git a/src/gui/painting/qpainter.h b/src/gui/painting/qpainter.h
index ae2fdf2..4b2c447 100644
--- a/src/gui/painting/qpainter.h
+++ b/src/gui/painting/qpainter.h
@@ -399,7 +399,9 @@ public:
     void setLayoutDirection(Qt::LayoutDirection direction);
     Qt::LayoutDirection layoutDirection() const;
 
+#if !defined(QT_NO_RAWFONT)
     void drawGlyphs(const QPointF &position, const QGlyphs &glyphs);
+#endif
 
     void drawStaticText(const QPointF &topLeftPosition, const QStaticText &staticText);
     inline void drawStaticText(const QPoint &topLeftPosition, const QStaticText &staticText);
diff --git a/src/gui/painting/qpainter_p.h b/src/gui/painting/qpainter_p.h
index 26d8fc3..205c10a 100644
--- a/src/gui/painting/qpainter_p.h
+++ b/src/gui/painting/qpainter_p.h
@@ -184,6 +184,7 @@ struct QPainterDummyState
     QTransform transform;
 };
 
+class QRawFont;
 class QPainterPrivate
 {
     Q_DECLARE_PUBLIC(QPainter)
@@ -229,7 +230,12 @@ public:
     void draw_helper(const QPainterPath &path, DrawOperation operation = StrokeAndFillDraw);
     void drawStretchedGradient(const QPainterPath &path, DrawOperation operation);
     void drawOpaqueBackground(const QPainterPath &path, DrawOperation operation);
-    void drawGlyphs(quint32 *glyphArray, QFixedPoint *positionArray, int glyphCount);
+
+#if !defined(QT_NO_RAWFONT)
+    void drawGlyphs(quint32 *glyphArray, QFixedPoint *positionArray, int glyphCount,
+                    const QRawFont &font, bool overline = false, bool underline = false,
+                    bool strikeOut = false);
+#endif
 
     void updateMatrix();
     void updateInvMatrix();
@@ -259,8 +265,6 @@ public:
 };
 
 Q_GUI_EXPORT void qt_draw_helper(QPainterPrivate *p, const QPainterPath &path, QPainterPrivate::DrawOperation operation);
-Q_GUI_EXPORT void qt_draw_glyphs(QPainter *painter, const quint32 *glyphArray,
-                                 const QPointF *positionArray, int glyphCount);
 
 QString qt_generate_brush_key(const QBrush &brush);