Enablers for shared graphics cache in raster paint engine

Required changes for using shared graphics cache for distance field
raster glyph rendering. Most of the logic is in platform plugins.

Platform plugins should implement
QPlatformIntegration::createImagePaintEngine() to create a subclass
of QRasterEngine.

Change-Id: Icf0a396e722e43b4caa2c1849aae38753cde38f1
Reviewed-by: Eskil Abrahamsen Blomfeldt <[email protected]>

16 files changed, 116 insertions, 56 deletions

diff --git a/src/gui/image/qimage.cpp b/src/gui/image/qimage.cpp
index 3e53b047280..61a3895a6b7 100644
--- a/src/gui/image/qimage.cpp
+++ b/src/gui/image/qimage.cpp
@@ -50,6 +50,7 @@
 #include "qstringlist.h"
 #include "qvariant.h"
 #include "qimagepixmapcleanuphooks_p.h"
+#include "qplatformintegration_qpa.h"
 #include <ctype.h>
 #include <stdlib.h>
 #include <limits.h>
@@ -62,6 +63,7 @@
 
 #include <qhash.h>
 
+#include <private/qguiapplication_p.h>
 #include <private/qpaintengine_raster_p.h>
 
 #include <private/qimage_p.h>
@@ -4900,7 +4902,9 @@ QPaintEngine *QImage::paintEngine() const
         return 0;
 
     if (!d->paintEngine) {
-        d->paintEngine = new QRasterPaintEngine(const_cast<QImage *>(this));
+        QPaintDevice *paintDevice = const_cast<QImage *>(this);
+        QPaintEngine *paintEngine = QGuiApplicationPrivate::platformIntegration()->createImagePaintEngine(paintDevice);
+        d->paintEngine = paintEngine ? paintEngine : new QRasterPaintEngine(paintDevice);
     }
 
     return d->paintEngine;
diff --git a/src/gui/kernel/qplatformintegration_qpa.cpp b/src/gui/kernel/qplatformintegration_qpa.cpp
index 7a3fe05f7a9..fd3714d3037 100644
--- a/src/gui/kernel/qplatformintegration_qpa.cpp
+++ b/src/gui/kernel/qplatformintegration_qpa.cpp
@@ -241,6 +241,15 @@ QPlatformSharedGraphicsCache *QPlatformIntegration::createPlatformSharedGraphics
 }
 
 /*!
+   Factory function for QPaintEngine. This function will return 0 if the platform
+   integration does not support creating any paint engine the given \a paintDevice.
+*/
+QPaintEngine *QPlatformIntegration::createImagePaintEngine(QPaintDevice *paintDevice) const
+{
+    return 0;
+}
+
+/*!
   Returns the platforms input context.
 
   The default implementation returns 0, implying no input method support.
diff --git a/src/gui/kernel/qplatformintegration_qpa.h b/src/gui/kernel/qplatformintegration_qpa.h
index 483964b8f38..a05c0f61b70 100644
--- a/src/gui/kernel/qplatformintegration_qpa.h
+++ b/src/gui/kernel/qplatformintegration_qpa.h
@@ -91,6 +91,7 @@ public:
     virtual QPlatformOpenGLContext *createPlatformOpenGLContext(QOpenGLContext *context) const;
 #endif
     virtual QPlatformSharedGraphicsCache *createPlatformSharedGraphicsCache(const char *cacheId) const;
+    virtual QPaintEngine *createImagePaintEngine(QPaintDevice *paintDevice) const;
 
 // Event dispatcher:
     virtual QAbstractEventDispatcher *guiThreadEventDispatcher() const = 0;
diff --git a/src/gui/opengl/qopenglpaintengine.cpp b/src/gui/opengl/qopenglpaintengine.cpp
index eb32ac162fa..73be87bc1dd 100644
--- a/src/gui/opengl/qopenglpaintengine.cpp
+++ b/src/gui/opengl/qopenglpaintengine.cpp
@@ -1405,8 +1405,7 @@ void QOpenGL2PaintEngineEx::drawStaticTextItem(QStaticTextItem *textItem)
 
     // don't try to cache huge fonts or vastly transformed fonts
     QFontEngine *fontEngine = textItem->fontEngine();
-    const qreal pixelSize = fontEngine->fontDef.pixelSize;
-    if (shouldDrawCachedGlyphs(pixelSize, s->matrix) || det < 0.25f || det > 4.f) {
+    if (shouldDrawCachedGlyphs(fontEngine, s->matrix) || det < 0.25f || det > 4.f) {
         QFontEngineGlyphCache::Type glyphType = fontEngine->glyphFormat >= 0
                                                 ? QFontEngineGlyphCache::Type(textItem->fontEngine()->glyphFormat)
                                                 : d->glyphCacheType;
@@ -1460,8 +1459,7 @@ void QOpenGL2PaintEngineEx::drawTextItem(const QPointF &p, const QTextItem &text
     bool drawCached = txtype < QTransform::TxProject;
 
     // don't try to cache huge fonts or vastly transformed fonts
-    const qreal pixelSize = ti.fontEngine->fontDef.pixelSize;
-    if (shouldDrawCachedGlyphs(pixelSize, s->matrix) || det < 0.25f || det > 4.f)
+    if (shouldDrawCachedGlyphs(ti.fontEngine, s->matrix) || det < 0.25f || det > 4.f)
         drawCached = false;
 
     QFontEngineGlyphCache::Type glyphType = ti.fontEngine->glyphFormat >= 0
diff --git a/src/gui/opengl/qopenglpaintengine_p.h b/src/gui/opengl/qopenglpaintengine_p.h
index 0a6ef2a4d22..1b3dfbae281 100644
--- a/src/gui/opengl/qopenglpaintengine_p.h
+++ b/src/gui/opengl/qopenglpaintengine_p.h
@@ -157,7 +157,7 @@ public:
     void setRenderTextActive(bool);
 
     bool isNativePaintingActive() const;
-    bool supportsTransformations(qreal, const QTransform &) const { return true; }
+    bool supportsTransformations(QFontEngine *, const QTransform &) const { return true; }
 
 private:
     Q_DISABLE_COPY(QOpenGL2PaintEngineEx)
diff --git a/src/gui/painting/qpaintengine_raster.cpp b/src/gui/painting/qpaintengine_raster.cpp
index f2aac442dc1..b5e8bca7e08 100644
--- a/src/gui/painting/qpaintengine_raster.cpp
+++ b/src/gui/painting/qpaintengine_raster.cpp
@@ -2467,6 +2467,15 @@ static inline bool monoVal(const uchar* s, int x)
 
 /*!
     \internal
+ */
+QRasterBuffer *QRasterPaintEngine::rasterBuffer()
+{
+    Q_D(QRasterPaintEngine);
+    return d->rasterBuffer.data();
+}
+
+/*!
+    \internal
 */
 void QRasterPaintEngine::alphaPenBlt(const void* src, int bpl, int depth, int rx,int ry,int w,int h)
 {
@@ -2923,7 +2932,7 @@ void QRasterPaintEngine::drawStaticTextItem(QStaticTextItem *textItem)
     ensureRasterState();
 
     QFontEngine *fontEngine = textItem->fontEngine();
-    if (shouldDrawCachedGlyphs(fontEngine->fontDef.pixelSize, state()->matrix)) {
+    if (shouldDrawCachedGlyphs(fontEngine, state()->matrix)) {
         drawCachedGlyphs(textItem->numGlyphs, textItem->glyphs, textItem->glyphPositions,
                          fontEngine);
     } else if (state()->matrix.type() < QTransform::TxProject) {
@@ -3207,18 +3216,18 @@ void QRasterPaintEngine::releaseDC(HDC) const
 
 #endif
 
-bool QRasterPaintEngine::supportsTransformations(const QFontEngine *fontEngine) const
+bool QRasterPaintEngine::supportsTransformations(QFontEngine *fontEngine) const
 {
     const QTransform &m = state()->matrix;
-    return supportsTransformations(fontEngine->fontDef.pixelSize, m);
+    return supportsTransformations(fontEngine, m);
 }
 
-bool QRasterPaintEngine::supportsTransformations(qreal pixelSize, const QTransform &m) const
+bool QRasterPaintEngine::supportsTransformations(QFontEngine *fontEngine, const QTransform &m) const
 {
     if (m.type() >= QTransform::TxProject)
         return true;
 
-    return !shouldDrawCachedGlyphs(pixelSize, m);
+    return !shouldDrawCachedGlyphs(fontEngine, m);
 }
 
 /*!
diff --git a/src/gui/painting/qpaintengine_raster_p.h b/src/gui/painting/qpaintengine_raster_p.h
index 7b353188a3c..79ed03e3930 100644
--- a/src/gui/painting/qpaintengine_raster_p.h
+++ b/src/gui/painting/qpaintengine_raster_p.h
@@ -194,8 +194,11 @@ public:
     void clip(const QVectorPath &path, Qt::ClipOperation op);
     void clip(const QRect &rect, Qt::ClipOperation op);
     void clip(const QRegion &region, Qt::ClipOperation op);
+    inline const QClipData *clip() const;
 
     void drawStaticTextItem(QStaticTextItem *textItem);
+    virtual bool drawCachedGlyphs(int numGlyphs, const glyph_t *glyphs, const QFixedPoint *positions,
+                                  QFontEngine *fontEngine);
 
     enum ClipType {
         RectClip,
@@ -227,14 +230,15 @@ public:
     static bool clearTypeFontsEnabled();
 #endif
 
+    QRasterBuffer *rasterBuffer();
     void alphaPenBlt(const void* src, int bpl, int depth, int rx,int ry,int w,int h);
 
     Type type() const { return Raster; }
 
     QPoint coordinateOffset() const;
 
-    bool supportsTransformations(const QFontEngine *fontEngine) const;
-    bool supportsTransformations(qreal pixelSize, const QTransform &m) const;
+    bool supportsTransformations(QFontEngine *fontEngine) const;
+    bool supportsTransformations(QFontEngine *fontEngine, const QTransform &m) const;
 
 protected:
     QRasterPaintEngine(QRasterPaintEnginePrivate &d, QPaintDevice *);
@@ -247,10 +251,6 @@ private:
     void fillRect(const QRectF &rect, QSpanData *data);
     void drawBitmap(const QPointF &pos, const QImage &image, QSpanData *fill);
 
-    bool drawCachedGlyphs(int numGlyphs, const glyph_t *glyphs, const QFixedPoint *positions,
-                          QFontEngine *fontEngine);
-
-
     bool setClipRectInDeviceCoords(const QRect &r, Qt::ClipOperation op);
 
     inline void ensureBrush(const QBrush &brush) {
@@ -492,6 +492,12 @@ inline const QClipData *QRasterPaintEnginePrivate::clip() const {
     return baseClip.data();
 }
 
+inline const QClipData *QRasterPaintEngine::clip() const {
+    Q_D(const QRasterPaintEngine);
+    if (state() && state()->clip && state()->clip->enabled)
+        return state()->clip;
+    return d->baseClip.data();
+}
 
 QT_END_NAMESPACE
 #endif // QPAINTENGINE_RASTER_P_H
diff --git a/src/gui/painting/qpaintengineex.cpp b/src/gui/painting/qpaintengineex.cpp
index 93f36ba0abc..36414f47741 100644
--- a/src/gui/painting/qpaintengineex.cpp
+++ b/src/gui/painting/qpaintengineex.cpp
@@ -1081,9 +1081,9 @@ void QPaintEngineEx::drawStaticTextItem(QStaticTextItem *staticTextItem)
     }
 }
 
-bool QPaintEngineEx::supportsTransformations(qreal pixelSize, const QTransform &m) const
+bool QPaintEngineEx::supportsTransformations(QFontEngine *fontEngine, const QTransform &m) const
 {
-    Q_UNUSED(pixelSize);
+    Q_UNUSED(fontEngine);
 
     if (!m.isAffine())
         return true;
@@ -1091,8 +1091,9 @@ bool QPaintEngineEx::supportsTransformations(qreal pixelSize, const QTransform &
     return false;
 }
 
-bool QPaintEngineEx::shouldDrawCachedGlyphs(qreal pixelSize, const QTransform &m) const
+bool QPaintEngineEx::shouldDrawCachedGlyphs(QFontEngine *fontEngine, const QTransform &m) const
 {
+    qreal pixelSize = fontEngine->fontDef.pixelSize;
     return (pixelSize * pixelSize * qAbs(m.determinant())) <
             QT_MAX_CACHED_GLYPH_SIZE * QT_MAX_CACHED_GLYPH_SIZE;
 }
diff --git a/src/gui/painting/qpaintengineex_p.h b/src/gui/painting/qpaintengineex_p.h
index 62c5d972de7..bc944b22976 100644
--- a/src/gui/painting/qpaintengineex_p.h
+++ b/src/gui/painting/qpaintengineex_p.h
@@ -226,8 +226,8 @@ public:
         IsEmulationEngine = 0x02    // If set, this object is a QEmulationEngine.
     };
     virtual uint flags() const {return 0;}
-    virtual bool supportsTransformations(qreal pixelSize, const QTransform &m) const;
-    virtual bool shouldDrawCachedGlyphs(qreal pixelSize, const QTransform &m) const;
+    virtual bool supportsTransformations(QFontEngine *fontEngine, const QTransform &m) const;
+    virtual bool shouldDrawCachedGlyphs(QFontEngine *fontEngine, const QTransform &m) const;
 
 protected:
     QPaintEngineEx(QPaintEngineExPrivate &data);
diff --git a/src/gui/painting/qpainter.cpp b/src/gui/painting/qpainter.cpp
index 0f5468df4e4..973dabc4cb5 100644
--- a/src/gui/painting/qpainter.cpp
+++ b/src/gui/painting/qpainter.cpp
@@ -5551,14 +5551,9 @@ void QPainter::drawGlyphRun(const QPointF &position, const QGlyphRun &glyphRun)
     QVarLengthArray<QFixedPoint, 128> fixedPointPositions(count);
 
     QRawFontPrivate *fontD = QRawFontPrivate::get(font);
-    bool supportsTransformations;
-    if (d->extended != 0) {
-        supportsTransformations = d->extended->supportsTransformations(fontD->fontEngine->fontDef.pixelSize,
-                                                                       d->state->matrix);
-    } else {
-        supportsTransformations = d->engine->type() == QPaintEngine::CoreGraphics
-                                  || d->state->matrix.isAffine();
-    }
+    bool supportsTransformations = d->extended
+        ? d->extended->supportsTransformations(fontD->fontEngine, d->state->matrix)
+        : d->engine->type() == QPaintEngine::CoreGraphics || d->state->matrix.isAffine();
 
     for (int i=0; i<count; ++i) {
         QPointF processedPosition = position + glyphPositions[i];
@@ -5739,7 +5734,7 @@ void QPainter::drawStaticText(const QPointF &topLeftPosition, const QStaticText
         return;
     }
 
-    bool supportsTransformations = d->extended->supportsTransformations(staticText_d->font.pixelSize(),
+    bool supportsTransformations = d->extended->supportsTransformations(staticText_d->font.d->engineForScript(QUnicodeTables::Common),
                                                                         d->state->matrix);
     if (supportsTransformations && !staticText_d->untransformedCoordinates) {
         staticText_d->untransformedCoordinates = true;
diff --git a/src/gui/text/qdistancefield.cpp b/src/gui/text/qdistancefield.cpp
index fb06a26c8f1..a1deb471754 100644
--- a/src/gui/text/qdistancefield.cpp
+++ b/src/gui/text/qdistancefield.cpp
@@ -692,17 +692,8 @@ static QImage makeDistanceField(int imgSize, const QPainterPath &path, int dfSca
     return image;
 }
 
-bool qt_fontHasNarrowOutlines(const QRawFont &f)
+static bool imageHasNarrowOutlines(const QImage &im)
 {
-    QRawFont font = f;
-    font.setPixelSize(QT_DISTANCEFIELD_DEFAULT_BASEFONTSIZE);
-    Q_ASSERT(font.isValid());
-
-    QVector<quint32> glyphIndices = font.glyphIndexesForString(QLatin1String("O"));
-    if (glyphIndices.size() < 1)
-        return false;
-
-    QImage im = font.alphaMapForGlyph(glyphIndices.at(0), QRawFont::PixelAntialiasing);
     if (im.isNull())
         return false;
 
@@ -742,6 +733,56 @@ bool qt_fontHasNarrowOutlines(const QRawFont &f)
     return minHThick == 1 || minVThick == 1;
 }
 
+bool qt_fontHasNarrowOutlines(QFontEngine *fontEngine)
+{
+    QFontEngine *fe = fontEngine->cloneWithSize(QT_DISTANCEFIELD_DEFAULT_BASEFONTSIZE);
+
+    QGlyphLayout glyphs;
+    glyph_t glyph;
+    glyphs.glyphs = &glyph;
+    int numGlyphs;
+    QChar *chars = QString(QLatin1String("O")).data();
+    fe->stringToCMap(chars, 1, &glyphs, &numGlyphs, QTextEngine::GlyphIndicesOnly);
+    QImage im = fe->alphaMapForGlyph(glyph, QFixed(), QTransform());
+    delete fe;
+
+    return imageHasNarrowOutlines(im);
+}
+
+bool qt_fontHasNarrowOutlines(const QRawFont &f)
+{
+    QRawFont font = f;
+    font.setPixelSize(QT_DISTANCEFIELD_DEFAULT_BASEFONTSIZE);
+    Q_ASSERT(font.isValid());
+
+    QVector<quint32> glyphIndices = font.glyphIndexesForString(QLatin1String("O"));
+    if (glyphIndices.size() < 1)
+        return false;
+
+    return imageHasNarrowOutlines(font.alphaMapForGlyph(glyphIndices.at(0),
+                                                        QRawFont::PixelAntialiasing));
+}
+
+static QImage renderDistanceFieldPath(const QPainterPath &path, bool doubleResolution)
+{
+    QImage im = makeDistanceField(QT_DISTANCEFIELD_TILESIZE(doubleResolution),
+                                  path,
+                                  QT_DISTANCEFIELD_SCALE(doubleResolution),
+                                  QT_DISTANCEFIELD_RADIUS(doubleResolution) / QT_DISTANCEFIELD_SCALE(doubleResolution));
+    return im;
+}
+
+QImage qt_renderDistanceFieldGlyph(QFontEngine *fe, glyph_t glyph, bool doubleResolution)
+{
+    QFixedPoint position;
+    QPainterPath path;
+    fe->addGlyphsToPath(&glyph, &position, 1, &path, 0);
+    path.translate(-path.boundingRect().topLeft());
+    path.setFillRule(Qt::WindingFill);
+
+    return renderDistanceFieldPath(path, doubleResolution);
+}
+
 QImage qt_renderDistanceFieldGlyph(const QRawFont &font, glyph_t glyph, bool doubleResolution)
 {
     QRawFont renderFont = font;
@@ -751,11 +792,7 @@ QImage qt_renderDistanceFieldGlyph(const QRawFont &font, glyph_t glyph, bool dou
     path.translate(-path.boundingRect().topLeft());
     path.setFillRule(Qt::WindingFill);
 
-    QImage im = makeDistanceField(QT_DISTANCEFIELD_TILESIZE(doubleResolution),
-                                  path,
-                                  QT_DISTANCEFIELD_SCALE(doubleResolution),
-                                  QT_DISTANCEFIELD_RADIUS(doubleResolution) / QT_DISTANCEFIELD_SCALE(doubleResolution));
-    return im;
+    return renderDistanceFieldPath(path, doubleResolution);
 }
 
 QT_END_NAMESPACE
diff --git a/src/gui/text/qdistancefield_p.h b/src/gui/text/qdistancefield_p.h
index 486d291b782..bf87e7d3cb7 100644
--- a/src/gui/text/qdistancefield_p.h
+++ b/src/gui/text/qdistancefield_p.h
@@ -79,6 +79,8 @@ QT_BEGIN_NAMESPACE
 
 bool Q_GUI_EXPORT qt_fontHasNarrowOutlines(const QRawFont &f);
 QImage Q_GUI_EXPORT qt_renderDistanceFieldGlyph(const QRawFont &font, glyph_t glyph, bool doubleResolution);
+bool Q_GUI_EXPORT qt_fontHasNarrowOutlines(QFontEngine *fontEngine);
+QImage Q_GUI_EXPORT qt_renderDistanceFieldGlyph(QFontEngine *fontEngine, glyph_t glyph, bool doubleResolution);
 
 QT_END_NAMESPACE
 
diff --git a/src/gui/text/qfontengine.cpp b/src/gui/text/qfontengine.cpp
index 53c5f9fc316..364a356b96c 100644
--- a/src/gui/text/qfontengine.cpp
+++ b/src/gui/text/qfontengine.cpp
@@ -775,7 +775,7 @@ QByteArray QFontEngine::getSfntTable(uint tag) const
     return table;
 }
 
-void QFontEngine::setGlyphCache(void *key, QFontEngineGlyphCache *data)
+void QFontEngine::setGlyphCache(const void *key, QFontEngineGlyphCache *data)
 {
     Q_ASSERT(data);
 
@@ -794,7 +794,7 @@ void QFontEngine::setGlyphCache(void *key, QFontEngineGlyphCache *data)
 
 }
 
-QFontEngineGlyphCache *QFontEngine::glyphCache(void *key, QFontEngineGlyphCache::Type type, const QTransform &transform) const
+QFontEngineGlyphCache *QFontEngine::glyphCache(const void *key, QFontEngineGlyphCache::Type type, const QTransform &transform) const
 {
     for (QLinkedList<GlyphCacheEntry>::const_iterator it = m_glyphCaches.constBegin(), end = m_glyphCaches.constEnd(); it != end; ++it) {
         QFontEngineGlyphCache *c = it->cache.data();
diff --git a/src/gui/text/qfontengine_p.h b/src/gui/text/qfontengine_p.h
index b4436426b2b..1114cdf12ca 100644
--- a/src/gui/text/qfontengine_p.h
+++ b/src/gui/text/qfontengine_p.h
@@ -239,8 +239,8 @@ public:
 
     virtual HB_Error getPointInOutline(HB_Glyph glyph, int flags, hb_uint32 point, HB_Fixed *xpos, HB_Fixed *ypos, hb_uint32 *nPoints);
 
-    void setGlyphCache(void *key, QFontEngineGlyphCache *data);
-    QFontEngineGlyphCache *glyphCache(void *key, QFontEngineGlyphCache::Type type, const QTransform &transform) const;
+    void setGlyphCache(const void *key, QFontEngineGlyphCache *data);
+    QFontEngineGlyphCache *glyphCache(const void *key, QFontEngineGlyphCache::Type type, const QTransform &transform) const;
 
     static const uchar *getCMap(const uchar *table, uint tableSize, bool *isSymbolFont, int *cmapSize);
     static quint32 getTrueTypeGlyphIndex(const uchar *cmap, uint unicode);
@@ -284,7 +284,7 @@ protected:
 
 private:
     struct GlyphCacheEntry {
-        void *context;
+        const void *context;
         QExplicitlySharedDataPointer<QFontEngineGlyphCache> cache;
         bool operator==(const GlyphCacheEntry &other) const { return context == other.context && cache == other.cache; }
     };
diff --git a/src/opengl/gl2paintengineex/qpaintengineex_opengl2.cpp b/src/opengl/gl2paintengineex/qpaintengineex_opengl2.cpp
index 29dab0e1e08..ca32adcd6fe 100644
--- a/src/opengl/gl2paintengineex/qpaintengineex_opengl2.cpp
+++ b/src/opengl/gl2paintengineex/qpaintengineex_opengl2.cpp
@@ -1432,8 +1432,7 @@ void QGL2PaintEngineEx::drawStaticTextItem(QStaticTextItem *textItem)
 
     // don't try to cache huge fonts or vastly transformed fonts
     QFontEngine *fontEngine = textItem->fontEngine();
-    const qreal pixelSize = fontEngine->fontDef.pixelSize;
-    if (shouldDrawCachedGlyphs(pixelSize, s->matrix) || det < 0.25f || det > 4.f) {
+    if (shouldDrawCachedGlyphs(fontEngine, s->matrix) || det < 0.25f || det > 4.f) {
         QFontEngineGlyphCache::Type glyphType = fontEngine->glyphFormat >= 0
                                                 ? QFontEngineGlyphCache::Type(textItem->fontEngine()->glyphFormat)
                                                 : d->glyphCacheType;
@@ -1491,8 +1490,7 @@ void QGL2PaintEngineEx::drawTextItem(const QPointF &p, const QTextItem &textItem
     bool drawCached = txtype < QTransform::TxProject;
 
     // don't try to cache huge fonts or vastly transformed fonts
-    const qreal pixelSize = ti.fontEngine->fontDef.pixelSize;
-    if (shouldDrawCachedGlyphs(pixelSize, s->matrix) || det < 0.25f || det > 4.f)
+    if (shouldDrawCachedGlyphs(ti.fontEngine, s->matrix) || det < 0.25f || det > 4.f)
         drawCached = false;
 
     QFontEngineGlyphCache::Type glyphType = ti.fontEngine->glyphFormat >= 0
diff --git a/src/opengl/gl2paintengineex/qpaintengineex_opengl2_p.h b/src/opengl/gl2paintengineex/qpaintengineex_opengl2_p.h
index c5d3417555d..8eeee334f5a 100644
--- a/src/opengl/gl2paintengineex/qpaintengineex_opengl2_p.h
+++ b/src/opengl/gl2paintengineex/qpaintengineex_opengl2_p.h
@@ -155,7 +155,7 @@ public:
     void setRenderTextActive(bool);
 
     bool isNativePaintingActive() const;
-    bool supportsTransformations(qreal, const QTransform &) const { return true; }
+    bool supportsTransformations(QFontEngine *, const QTransform &) const { return true; }
 private:
     Q_DISABLE_COPY(QGL2PaintEngineEx)
 };