Move glyphMargin() to QFontEngine

glyphMargin() support for QTextureGlyphCache is implemented in
respective font engines, thus this function is platform dependent.
Before Qt 5 the code is guarded in macros like #ifdef Q_WS_MAC,
now we should move them into QFontEngine and its subclasses.

So far only Windows font engines support it. FreeType and Core Text
based font engines all ignore it.

Change-Id: Ia14016533d8fbfaacf848a7d3bc928f8197318f5
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@nokia.com>

11 files changed, 23 insertions, 27 deletions

diff --git a/src/gui/opengl/qopenglpaintengine.cpp b/src/gui/opengl/qopenglpaintengine.cpp
index 5cbc646e84..359605cdb1 100644
--- a/src/gui/opengl/qopenglpaintengine.cpp
+++ b/src/gui/opengl/qopenglpaintengine.cpp
@@ -1581,7 +1581,7 @@ void QOpenGL2PaintEngineExPrivate::drawCachedGlyphs(QFontEngineGlyphCache::Type
 
     transferMode(TextDrawingMode);
 
-    int margin = cache->glyphMargin();
+    int margin = fe->glyphMargin(glyphType);
 
     GLfloat dx = 1.0 / cache->width();
     GLfloat dy = 1.0 / cache->height();
diff --git a/src/gui/painting/qpaintengine_raster.cpp b/src/gui/painting/qpaintengine_raster.cpp
index c53eda4d94..1e2e340c8a 100644
--- a/src/gui/painting/qpaintengine_raster.cpp
+++ b/src/gui/painting/qpaintengine_raster.cpp
@@ -2747,7 +2747,7 @@ bool QRasterPaintEngine::drawCachedGlyphs(int numGlyphs, const glyph_t *glyphs,
         else if (depth == 1)
             rightShift = 3; // divide by 8
 
-        int margin = cache->glyphMargin();
+        int margin = fontEngine->glyphMargin(glyphType);
         const QFixed offs = QFixed::fromReal(aliasedCoordinateDelta);
         const uchar *bits = image.bits();
         for (int i=0; i<numGlyphs; ++i) {
diff --git a/src/gui/painting/qtextureglyphcache.cpp b/src/gui/painting/qtextureglyphcache.cpp
index 161c6649f7..d5d4c53495 100644
--- a/src/gui/painting/qtextureglyphcache.cpp
+++ b/src/gui/painting/qtextureglyphcache.cpp
@@ -108,7 +108,7 @@ bool QTextureGlyphCache::populate(QFontEngine *fontEngine, int numGlyphs, const
 #endif
 
     m_current_fontengine = fontEngine;
-    const int margin = glyphMargin();
+    const int margin = m_current_fontengine->glyphMargin(m_type);
     const int paddingDoubled = glyphPadding() * 2;
 
     bool supportsSubPixelPositions = fontEngine->supportsSubPixelPositions();
@@ -274,7 +274,7 @@ void QTextureGlyphCache::fillInPendingGlyphs()
 QImage QTextureGlyphCache::textureMapForGlyph(glyph_t g, QFixed subPixelPosition) const
 {
     if (m_type == QFontEngineGlyphCache::Raster_RGBMask)
-        return m_current_fontengine->alphaRGBMapForGlyph(g, subPixelPosition, glyphMargin(), m_transform);
+        return m_current_fontengine->alphaRGBMapForGlyph(g, subPixelPosition, m_transform);
     else
         return m_current_fontengine->alphaMapForGlyph(g, subPixelPosition, m_transform);
 
@@ -311,11 +311,6 @@ void QImageTextureGlyphCache::createTextureData(int width, int height)
     }
 }
 
-int QImageTextureGlyphCache::glyphMargin() const
-{
-    return m_type == QFontEngineGlyphCache::Raster_RGBMask ? 2 : 0;
-}
-
 void QImageTextureGlyphCache::fillTexture(const Coord &c, glyph_t g, QFixed subPixelPosition)
 {
     QImage mask = textureMapForGlyph(g, subPixelPosition);
@@ -400,7 +395,8 @@ void QImageTextureGlyphCache::fillTexture(const Coord &c, glyph_t g, QFixed subP
 #ifdef CACHE_DEBUG
 //     QPainter p(&m_image);
 //     p.drawLine(
-    QPoint base(c.x + glyphMargin(), c.y + glyphMargin() + c.baseLineY-1);
+    int margin = m_current_fontengine ? m_current_fontengine->glyphMargin(m_type) : 0;
+    QPoint base(c.x + margin, c.y + margin + c.baseLineY-1);
     if (m_image.rect().contains(base))
         m_image.setPixel(base, 255);
     m_image.save(QString::fromLatin1("cache-%1.png").arg(qint64(this)));
diff --git a/src/gui/painting/qtextureglyphcache_p.h b/src/gui/painting/qtextureglyphcache_p.h
index eb0c968740..8f852b37d3 100644
--- a/src/gui/painting/qtextureglyphcache_p.h
+++ b/src/gui/painting/qtextureglyphcache_p.h
@@ -120,7 +120,6 @@ public:
 
     virtual void createTextureData(int width, int height) = 0;
     virtual void resizeTextureData(int width, int height) = 0;
-    virtual int glyphMargin() const { return 0; }
     virtual int glyphPadding() const { return 0; }
 
     virtual void fillTexture(const Coord &coord, glyph_t glyph, QFixed subPixelPosition) = 0;
@@ -170,7 +169,6 @@ class Q_GUI_EXPORT QImageTextureGlyphCache : public QTextureGlyphCache
 public:
     QImageTextureGlyphCache(QFontEngineGlyphCache::Type type, const QTransform &matrix)
         : QTextureGlyphCache(type, matrix) { }
-    virtual int glyphMargin() const;
     virtual void createTextureData(int width, int height);
     virtual void resizeTextureData(int width, int height);
     virtual void fillTexture(const Coord &c, glyph_t glyph, QFixed subPixelPosition);
diff --git a/src/gui/text/qfontengine.cpp b/src/gui/text/qfontengine.cpp
index 3894644f41..9303c65bac 100644
--- a/src/gui/text/qfontengine.cpp
+++ b/src/gui/text/qfontengine.cpp
@@ -618,7 +618,7 @@ QImage QFontEngine::alphaMapForGlyph(glyph_t glyph, QFixed subPixelPosition, con
     return i;
 }
 
-QImage QFontEngine::alphaRGBMapForGlyph(glyph_t glyph, QFixed /*subPixelPosition*/, int /* margin */, const QTransform &t)
+QImage QFontEngine::alphaRGBMapForGlyph(glyph_t glyph, QFixed /*subPixelPosition*/, const QTransform &t)
 {
     QImage alphaMask = alphaMapForGlyph(glyph, t);
     QImage rgbMask(alphaMask.width(), alphaMask.height(), QImage::Format_RGB32);
@@ -664,7 +664,7 @@ QImage *QFontEngine::lockedAlphaMapForGlyph(glyph_t glyph, QFixed subPixelPositi
     if (neededFormat != Format_A32)
         currentlyLockedAlphaMap = alphaMapForGlyph(glyph, subPixelPosition, t);
     else
-        currentlyLockedAlphaMap = alphaRGBMapForGlyph(glyph, subPixelPosition, 0, t);
+        currentlyLockedAlphaMap = alphaRGBMapForGlyph(glyph, subPixelPosition, t);
 
     if (offset != 0)
         *offset = QPoint(0, 0);
@@ -1747,11 +1747,11 @@ QImage QFontEngineMulti::alphaMapForGlyph(glyph_t glyph, QFixed subPixelPosition
     return engine(which)->alphaMapForGlyph(stripped(glyph), subPixelPosition, t);
 }
 
-QImage QFontEngineMulti::alphaRGBMapForGlyph(glyph_t glyph, QFixed subPixelPosition, int margin, const QTransform &t)
+QImage QFontEngineMulti::alphaRGBMapForGlyph(glyph_t glyph, QFixed subPixelPosition, const QTransform &t)
 {
     const int which = highByte(glyph);
     Q_ASSERT(which < engines.size());
-    return engine(which)->alphaRGBMapForGlyph(stripped(glyph), subPixelPosition, margin, t);
+    return engine(which)->alphaRGBMapForGlyph(stripped(glyph), subPixelPosition, t);
 }
 
 QT_END_NAMESPACE
diff --git a/src/gui/text/qfontengine_ft.cpp b/src/gui/text/qfontengine_ft.cpp
index 6fdb04ef61..31882af8bd 100644
--- a/src/gui/text/qfontengine_ft.cpp
+++ b/src/gui/text/qfontengine_ft.cpp
@@ -1896,17 +1896,17 @@ QImage QFontEngineFT::alphaMapForGlyph(glyph_t g, QFixed subPixelPosition)
     return img;
 }
 
-QImage QFontEngineFT::alphaRGBMapForGlyph(glyph_t g, QFixed subPixelPosition, int margin, const QTransform &t)
+QImage QFontEngineFT::alphaRGBMapForGlyph(glyph_t g, QFixed subPixelPosition, const QTransform &t)
 {
     if (t.type() > QTransform::TxTranslate)
-        return QFontEngine::alphaRGBMapForGlyph(g, subPixelPosition, margin, t);
+        return QFontEngine::alphaRGBMapForGlyph(g, subPixelPosition, t);
 
     lockFace();
 
     Glyph *glyph = loadGlyphFor(g, subPixelPosition, Format_A32);
     if (!glyph) {
         unlockFace();
-        return QFontEngine::alphaRGBMapForGlyph(g, subPixelPosition, margin, t);
+        return QFontEngine::alphaRGBMapForGlyph(g, subPixelPosition, t);
     }
 
     QImage img(glyph->width, glyph->height, QImage::Format_RGB32);
diff --git a/src/gui/text/qfontengine_ft_p.h b/src/gui/text/qfontengine_ft_p.h
index 577b46c776..aaea1ea5fb 100644
--- a/src/gui/text/qfontengine_ft_p.h
+++ b/src/gui/text/qfontengine_ft_p.h
@@ -255,7 +255,7 @@ private:
     virtual void recalcAdvances(QGlyphLayout *glyphs, QTextEngine::ShaperFlags flags) const;
     virtual QImage alphaMapForGlyph(glyph_t g) { return alphaMapForGlyph(g, 0); }
     virtual QImage alphaMapForGlyph(glyph_t, QFixed);
-    virtual QImage alphaRGBMapForGlyph(glyph_t, QFixed subPixelPosition, int margin, const QTransform &t);
+    virtual QImage alphaRGBMapForGlyph(glyph_t, QFixed subPixelPosition, const QTransform &t);
     virtual glyph_metrics_t alphaMapBoundingBox(glyph_t glyph,
                                                 QFixed subPixelPosition,
                                                 const QTransform &matrix,
@@ -267,6 +267,7 @@ private:
     virtual void unlockAlphaMapForGlyph();
 
     virtual void removeGlyphFromCache(glyph_t glyph);
+    virtual int glyphMargin(QFontEngineGlyphCache::Type type) { return 0; }
 
     virtual int glyphCount() const;
 
diff --git a/src/gui/text/qfontengine_p.h b/src/gui/text/qfontengine_p.h
index cb3a0e111d..6fd83b06a6 100644
--- a/src/gui/text/qfontengine_p.h
+++ b/src/gui/text/qfontengine_p.h
@@ -189,7 +189,7 @@ public:
     virtual QImage alphaMapForGlyph(glyph_t glyph, QFixed subPixelPosition);
     virtual QImage alphaMapForGlyph(glyph_t, const QTransform &t);
     virtual QImage alphaMapForGlyph(glyph_t, QFixed subPixelPosition, const QTransform &t);
-    virtual QImage alphaRGBMapForGlyph(glyph_t, QFixed subPixelPosition, int margin, const QTransform &t);
+    virtual QImage alphaRGBMapForGlyph(glyph_t, QFixed subPixelPosition, const QTransform &t);
     virtual QImage *lockedAlphaMapForGlyph(glyph_t glyph, QFixed subPixelPosition,
                                            GlyphFormat neededFormat,
                                            const QTransform &t = QTransform(),
@@ -231,6 +231,7 @@ public:
     virtual Type type() const = 0;
 
     virtual int glyphCount() const;
+    virtual int glyphMargin(QFontEngineGlyphCache::Type type) { return type == QFontEngineGlyphCache::Raster_RGBMask ? 2 : 0; }
 
     virtual QFontEngine *cloneWithSize(qreal /*pixelSize*/) const { return 0; }
 
@@ -370,7 +371,7 @@ public:
     virtual QImage alphaMapForGlyph(glyph_t glyph, QFixed subPixelPosition);
     virtual QImage alphaMapForGlyph(glyph_t, const QTransform &t);
     virtual QImage alphaMapForGlyph(glyph_t, QFixed subPixelPosition, const QTransform &t);
-    virtual QImage alphaRGBMapForGlyph(glyph_t, QFixed subPixelPosition, int margin, const QTransform &t);
+    virtual QImage alphaRGBMapForGlyph(glyph_t, QFixed subPixelPosition, const QTransform &t);
 
     virtual QFixed lineThickness() const;
     virtual QFixed underlinePosition() const;
diff --git a/src/gui/text/qfontenginedirectwrite.cpp b/src/gui/text/qfontenginedirectwrite.cpp
index 84dfe606e7..411642f231 100644
--- a/src/gui/text/qfontenginedirectwrite.cpp
+++ b/src/gui/text/qfontenginedirectwrite.cpp
@@ -641,10 +641,11 @@ QImage QFontEngineDirectWrite::imageForGlyph(glyph_t t,
 
 QImage QFontEngineDirectWrite::alphaRGBMapForGlyph(glyph_t t,
                                                    QFixed subPixelPosition,
-                                                   int margin,
                                                    const QTransform &xform)
 {
-    QImage mask = imageForGlyph(t, subPixelPosition, margin, xform);
+    QImage mask = imageForGlyph(t, subPixelPosition,
+                                glyphMargin(QFontEngineGlyphCache::Raster_RGBMask),
+                                xform);
     return mask.depth() == 32
            ? mask
            : mask.convertToFormat(QImage::Format_RGB32);
diff --git a/src/gui/text/qfontenginedirectwrite_p.h b/src/gui/text/qfontenginedirectwrite_p.h
index de263c6214..f614b0497f 100644
--- a/src/gui/text/qfontenginedirectwrite_p.h
+++ b/src/gui/text/qfontenginedirectwrite_p.h
@@ -102,8 +102,7 @@ public:
     bool supportsSubPixelPositions() const;
 
     QImage alphaMapForGlyph(glyph_t, QFixed subPixelPosition, const QTransform &t);
-    QImage alphaRGBMapForGlyph(glyph_t t, QFixed subPixelPosition, int margin,
-                               const QTransform &xform);
+    QImage alphaRGBMapForGlyph(glyph_t t, QFixed subPixelPosition, const QTransform &xform);
 
     QFontEngine *cloneWithSize(qreal pixelSize) const;
 
diff --git a/src/gui/text/qrawfont.cpp b/src/gui/text/qrawfont.cpp
index 15d0d0ce20..7bd515366d 100644
--- a/src/gui/text/qrawfont.cpp
+++ b/src/gui/text/qrawfont.cpp
@@ -250,7 +250,7 @@ QImage QRawFont::alphaMapForGlyph(quint32 glyphIndex, AntialiasingType antialias
         return QImage();
 
     if (antialiasingType == SubPixelAntialiasing)
-        return d->fontEngine->alphaRGBMapForGlyph(glyphIndex, QFixed(), 0, transform);
+        return d->fontEngine->alphaRGBMapForGlyph(glyphIndex, QFixed(), transform);
 
     return d->fontEngine->alphaMapForGlyph(glyphIndex, QFixed(), transform);
 }