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

1 files changed, 47 insertions, 11 deletions

diff --git a/src/gui/text/qtextlayout.cpp b/src/gui/text/qtextlayout.cpp
index afe6949..93f71d3 100644
--- a/src/gui/text/qtextlayout.cpp
+++ b/src/gui/text/qtextlayout.cpp
@@ -54,12 +54,18 @@
 #include "qpainterpath.h"
 #include "qglyphs.h"
 #include "qglyphs_p.h"
+#include "qrawfont.h"
+#include "qrawfont_p.h"
 #include <limits.h>
 
 #include <qdebug.h>
 
 #include "qfontengine_p.h"
 
+#if !defined(QT_NO_FREETYPE)
+#  include "qfontengine_ft_p.h"
+#endif
+
 QT_BEGIN_NAMESPACE
 
 #define ObjectSelectionBrush (QTextFormat::ForegroundBrush + 1)
@@ -1158,6 +1164,7 @@ static inline QRectF clipIfValid(const QRectF &rect, const QRectF &clip)
 
     \sa draw(), QPainter::drawGlyphs()
 */
+#if !defined(QT_NO_RAWFONT)
 QList<QGlyphs> QTextLayout::glyphs() const
 {
     QList<QGlyphs> glyphs;
@@ -1166,6 +1173,7 @@ QList<QGlyphs> QTextLayout::glyphs() const
 
     return glyphs;
 }
+#endif // QT_NO_RAWFONT
 
 /*!
     Draws the whole layout on the painter \a p at the position specified by \a pos.
@@ -2257,6 +2265,7 @@ namespace {
 
     \sa QTextLayout::glyphs()
 */
+#if !defined(QT_NO_RAWFONT)
 QList<QGlyphs> QTextLine::glyphs(int from, int length) const
 {
     const QScriptLine &line = eng->lines[i];
@@ -2331,7 +2340,35 @@ QList<QGlyphs> QTextLine::glyphs(int from, int length) const
         QFontEngine *fontEngine = keys.at(i);
 
         // Make a font for this particular engine
-        QFont font = fontEngine->createExplicitFont();
+        QRawFont font;
+        QRawFontPrivate *fontD = QRawFontPrivate::get(font);
+        fontD->fontEngine = fontEngine;
+        fontD->fontEngine->ref.ref();
+
+#if defined(Q_WS_WIN)
+        if (fontEngine->supportsSubPixelPositions())
+            fontD->hintingPreference = QFont::PreferVerticalHinting;
+        else
+            fontD->hintingPreference = QFont::PreferFullHinting;
+#elif defined(Q_WS_MAC)
+        fontD->hintingPreference = QFont::PreferNoHinting;
+#elif !defined(QT_NO_FREETYPE)
+        if (fontEngine->type() == QFontEngine::Freetype) {
+            QFontEngineFT *freeTypeEngine = static_cast<QFontEngineFT *>(fontEngine);
+            switch (freeTypeEngine->defaultHintStyle()) {
+            case QFontEngineFT::HintNone:
+                fontD->hintingPreference = QFont::PreferNoHinting;
+                break;
+            case QFontEngineFT::HintLight:
+                fontD->hintingPreference = QFont::PreferVerticalHinting;
+                break;
+            case QFontEngineFT::HintMedium:
+            case QFontEngineFT::HintFull:
+                fontD->hintingPreference = QFont::PreferFullHinting;
+                break;
+            };
+        }
+#endif
 
         QList<GlyphInfo> glyphLayouts = glyphLayoutHash.values(fontEngine);
         for (int j=0; j<glyphLayouts.size(); ++j) {
@@ -2339,10 +2376,6 @@ QList<QGlyphs> QTextLine::glyphs(int from, int length) const
             const QGlyphLayout &glyphLayout = glyphLayouts.at(j).glyphLayout;
             const QTextItem::RenderFlags &flags = glyphLayouts.at(j).flags;            
 
-            font.setOverline(flags.testFlag(QTextItem::Overline));
-            font.setUnderline(flags.testFlag(QTextItem::Underline));
-            font.setStrikeOut(flags.testFlag(QTextItem::StrikeOut));
-
             QVarLengthArray<glyph_t> glyphsArray;
             QVarLengthArray<QFixedPoint> positionsArray;
 
@@ -2361,19 +2394,22 @@ QList<QGlyphs> QTextLine::glyphs(int from, int length) const
             glyphIndexes.setGlyphIndexes(glyphs);
             glyphIndexes.setPositions(positions);
 
-            QPair<QFontEngine *, int> key(fontEngine, int(flags));
+            glyphIndexes.setOverline(flags.testFlag(QTextItem::Overline));
+            glyphIndexes.setUnderline(flags.testFlag(QTextItem::Underline));
+            glyphIndexes.setStrikeOut(flags.testFlag(QTextItem::StrikeOut));
+            glyphIndexes.setFont(font);
 
+            QPair<QFontEngine *, int> key(fontEngine, int(flags));
             if (!glyphsHash.contains(key))
-                glyphsHash.insert(key, QGlyphs());
-
-            QGlyphs &target = glyphsHash[key];
-            target += glyphIndexes;
-            target.setFont(font);
+                glyphsHash.insert(key, glyphIndexes);
+            else
+                glyphsHash[key] += glyphIndexes;
         }
     }
 
     return glyphsHash.values();
 }
+#endif // QT_NO_RAWFONT
 
 /*!
     \fn void QTextLine::draw(QPainter *painter, const QPointF &position, const QTextLayout::FormatRange *selection) const