Merge commit 'c1f9978c9d61bcbdb2f280185a3abdea13d7f532' into master-from-4.7

18 files changed, 184 insertions, 132 deletions

diff --git a/src/corelib/codecs/qtextcodec.cpp b/src/corelib/codecs/qtextcodec.cpp
index c9fbec8..83e1f0c 100644
--- a/src/corelib/codecs/qtextcodec.cpp
+++ b/src/corelib/codecs/qtextcodec.cpp
@@ -110,6 +110,10 @@ Q_GLOBAL_STATIC_WITH_ARGS(QFactoryLoader, loader,
     (QTextCodecFactoryInterface_iid, QLatin1String("/codecs")))
 #endif
 
+//Cache for QTextCodec::codecForName and codecForMib.
+typedef QHash<QByteArray, QTextCodec *> QTextCodecCache;
+Q_GLOBAL_STATIC(QTextCodecCache, qTextCodecCache)
+
 
 static char qtolower(register char c)
 { if (c >= 'A' && c <= 'Z') return c + 0x20; return c; }
@@ -181,7 +185,6 @@ static QTextCodec *createForMib(int mib)
 }
 
 static QList<QTextCodec*> *all = 0;
-static int clearCaches = 0;  // flags specifying if caches should be invalided: 0x1 codecForName, 0x2 codecForMib
 #ifdef Q_DEBUG_TEXTCODEC
 static bool destroying_is_ok = false;
 #endif
@@ -1007,7 +1010,9 @@ QTextCodec::~QTextCodec()
         QMutexLocker locker(textCodecsMutex());
 #endif
         all->removeAll(this);
-        clearCaches = 0x1 | 0x2;
+        QTextCodecCache *cache = qTextCodecCache();
+        if (cache)
+            cache->clear();
     }
 }
 
@@ -1037,32 +1042,33 @@ QTextCodec *QTextCodec::codecForName(const QByteArray &name)
     if (!validCodecs())
         return 0;
 
-    static QHash <QByteArray, QTextCodec *> cache;
-    if (clearCaches & 0x1) {
-        cache.clear();
-        clearCaches &= ~0x1;
+    QTextCodecCache *cache = qTextCodecCache();
+    QTextCodec *codec;
+    if (cache) {
+        codec = cache->value(name);
+        if (codec)
+            return codec;
     }
-    QTextCodec *codec = cache.value(name);
-    if (codec)
-        return codec;
 
     for (int i = 0; i < all->size(); ++i) {
         QTextCodec *cursor = all->at(i);
         if (nameMatch(cursor->name(), name)) {
-            cache.insert(name, cursor);
+            if (cache)
+                cache->insert(name, cursor);
             return cursor;
         }
         QList<QByteArray> aliases = cursor->aliases();
         for (int y = 0; y < aliases.size(); ++y)
             if (nameMatch(aliases.at(y), name)) {
-                cache.insert(name, cursor);
+                if (cache)
+                    cache->insert(name, cursor);
                 return cursor;
             }
     }
 
     codec = createForName(name);
-    if (codec)
-        cache.insert(name, codec);
+    if (codec && cache)
+        cache->insert(name, codec);
     return codec;
 }
 
@@ -1081,20 +1087,18 @@ QTextCodec* QTextCodec::codecForMib(int mib)
     if (!validCodecs())
         return 0;
 
-    static QHash <int, QTextCodec *> cache;
-    if (clearCaches & 0x2) {
-        cache.clear();
-        clearCaches &= ~0x2;
-    }
-    QTextCodec *codec = cache.value(mib);
-    if (codec)
-        return codec;
+    QByteArray key = "MIB: " + QByteArray::number(mib);
+    QTextCodecCache *cache = qTextCodecCache();
+    QTextCodec *codec;
+    if (cache)
+        codec = cache->value(key);
 
     QList<QTextCodec*>::ConstIterator i;
     for (int i = 0; i < all->size(); ++i) {
         QTextCodec *cursor = all->at(i);
         if (cursor->mibEnum() == mib) {
-            cache.insert(mib, cursor);
+            if (cache)
+                cache->insert(key, cursor);
             return cursor;
         }
     }
@@ -1106,8 +1110,8 @@ QTextCodec* QTextCodec::codecForMib(int mib)
     if (!codec && mib == 1000)
         return codecForMib(1015);
 
-    if (codec)
-        cache.insert(mib, codec);
+    if (codec && cache)
+        cache->insert(key, codec);
     return codec;
 }
 
diff --git a/src/gui/dialogs/qprintdialog_mac.mm b/src/gui/dialogs/qprintdialog_mac.mm
index 84a72db..82e4db5 100644
--- a/src/gui/dialogs/qprintdialog_mac.mm
+++ b/src/gui/dialogs/qprintdialog_mac.mm
@@ -140,11 +140,6 @@ QT_USE_NAMESPACE
 
     QPrintDialogPrivate *d = static_cast<QPrintDialogPrivate *>(contextInfo);
     QPrintDialog *dialog = d->printDialog();
-    // temporary hack to work around bug in deleteLater() in Qt/Mac Cocoa
-#if 1
-    bool deleteDialog = dialog->testAttribute(Qt::WA_DeleteOnClose);
-    dialog->setAttribute(Qt::WA_DeleteOnClose, false);
-#endif
 
     if (returnCode == NSOKButton) {
         UInt32 frompage, topage;
@@ -192,10 +187,6 @@ QT_USE_NAMESPACE
     }
 
     dialog->done((returnCode == NSOKButton) ? QDialog::Accepted : QDialog::Rejected);
-#if 1
-    if (deleteDialog)
-        delete dialog;
-#endif
 }
 @end
 
diff --git a/src/gui/graphicsview/qgraphicslinearlayout.cpp b/src/gui/graphicsview/qgraphicslinearlayout.cpp
index 1588364..7e8d19f 100644
--- a/src/gui/graphicsview/qgraphicslinearlayout.cpp
+++ b/src/gui/graphicsview/qgraphicslinearlayout.cpp
@@ -275,13 +275,17 @@ void QGraphicsLinearLayout::insertItem(int index, QGraphicsLayoutItem *item)
         qWarning("QGraphicsLinearLayout::insertItem: cannot insert itself");
         return;
     }
+    Q_ASSERT(item);
+
+    //the order of the following instructions is very important because
+    //invalidating the layout before adding the child item will make the layout happen
+    //before we try to paint the item
+    invalidate();
     d->addChildLayoutItem(item);
 
-    Q_ASSERT(item);
     d->fixIndex(&index);
     d->engine.insertRow(index, d->orientation);
     new QGridLayoutItem(&d->engine, item, d->gridRow(index), d->gridColumn(index), 1, 1, 0, index);
-    invalidate();
 }
 
 /*!
diff --git a/src/gui/graphicsview/qgridlayoutengine.cpp b/src/gui/graphicsview/qgridlayoutengine.cpp
index 98e6781..f8cd593 100644
--- a/src/gui/graphicsview/qgridlayoutengine.cpp
+++ b/src/gui/graphicsview/qgridlayoutengine.cpp
@@ -306,20 +306,19 @@ void QGridLayoutRowData::calculateGeometries(int start, int end, qreal targetSiz
                         ultimatePreferredSize = ultimatePreferredSize * 3 / 2;
                         ultimateSumPreferredSizes = ultimateSumPreferredSizes * 3 / 2;
 
-                        qreal ultimateFactor = (stretch * ultimateSumPreferredSizes
-                                                / sumStretches)
-                                               - (box.q_preferredSize);
-                        qreal transitionalFactor = sumCurrentAvailable
-                                                   * (ultimatePreferredSize - box.q_preferredSize)
-                                                   / (ultimateSumPreferredSizes
-                                                      - sumPreferredSizes);
-
-                        qreal alpha = qMin(sumCurrentAvailable,
-                                           ultimateSumPreferredSizes - sumPreferredSizes);
                         qreal beta = ultimateSumPreferredSizes - sumPreferredSizes;
+                        if (!beta) {
+                            factors[i] = 1;
+                        } else {
+                            qreal alpha = qMin(sumCurrentAvailable, beta);
+                            qreal ultimateFactor = (stretch * ultimateSumPreferredSizes / sumStretches)
+                                                   - (box.q_preferredSize);
+                            qreal transitionalFactor = sumCurrentAvailable * (ultimatePreferredSize - box.q_preferredSize) / beta;
+
+                            factors[i] = ((alpha * ultimateFactor)
+                                          + ((beta - alpha) * transitionalFactor)) / beta;
+                        }
 
-                        factors[i] = ((alpha * ultimateFactor)
-                                      + ((beta - alpha) * transitionalFactor)) / beta;
                     }
                     sumFactors += factors[i];
                     if (desired < sumCurrentAvailable)
diff --git a/src/gui/image/qgifhandler.cpp b/src/gui/image/qgifhandler.cpp
index 124d27b..a050baf 100644
--- a/src/gui/image/qgifhandler.cpp
+++ b/src/gui/image/qgifhandler.cpp
@@ -505,17 +505,26 @@ int QGIFFormat::decode(QImage *image, const uchar *buffer, int length,
                             code=oldcode;
                         }
                         while (code>=clear_code+2) {
+                            if (code >= max_code) {
+                                state = Error;
+                                return -1;
+                            }
                             *sp++=table[1][code];
                             if (code==table[0][code]) {
                                 state=Error;
-                                break;
+                                return -1;
                             }
                             if (sp-stack>=(1<<(max_lzw_bits))*2) {
                                 state=Error;
-                                break;
+                                return -1;
                             }
                             code=table[0][code];
                         }
+                        if (code < 0) {
+                            state = Error;
+                            return -1;
+                        }
+
                         *sp++=firstcode=table[1][code];
                         code=max_code;
                         if (code<(1<<max_lzw_bits)) {
diff --git a/src/gui/image/qjpeghandler.cpp b/src/gui/image/qjpeghandler.cpp
index b9eda05..d47cc82 100644
--- a/src/gui/image/qjpeghandler.cpp
+++ b/src/gui/image/qjpeghandler.cpp
@@ -648,22 +648,28 @@ static bool write_jpeg_image(const QImage &image, QIODevice *device, int sourceQ
                 break;
             case QImage::Format_RGB32:
             case QImage::Format_ARGB32:
-            case QImage::Format_ARGB32_Premultiplied: {
-                const QRgb* rgb = (const QRgb*)image.constScanLine(cinfo.next_scanline);
-                for (int i=0; i<w; i++) {
-                    *row++ = qRed(*rgb);
-                    *row++ = qGreen(*rgb);
-                    *row++ = qBlue(*rgb);
-                    ++rgb;
+            case QImage::Format_ARGB32_Premultiplied:
+                {
+                    const QRgb* rgb = (const QRgb*)image.constScanLine(cinfo.next_scanline);
+                    for (int i=0; i<w; i++) {
+                        *row++ = qRed(*rgb);
+                        *row++ = qGreen(*rgb);
+                        *row++ = qBlue(*rgb);
+                        ++rgb;
+                    }
                 }
                 break;
-            }
             default:
-                for (int i=0; i<w; i++) {
-                    QRgb pix = image.pixel(i, cinfo.next_scanline);
-                    *row++ = qRed(pix);
-                    *row++ = qGreen(pix);
-                    *row++ = qBlue(pix);
+                {
+                    // (Testing shows that this way is actually faster than converting to RGB888 + memcpy)
+                    QImage rowImg = image.copy(0, cinfo.next_scanline, w, 1).convertToFormat(QImage::Format_RGB32);
+                    const QRgb* rgb = (const QRgb*)rowImg.constScanLine(0);
+                    for (int i=0; i<w; i++) {
+                        *row++ = qRed(*rgb);
+                        *row++ = qGreen(*rgb);
+                        *row++ = qBlue(*rgb);
+                        ++rgb;
+                    }
                 }
                 break;
             }
diff --git a/src/gui/image/qpnghandler.cpp b/src/gui/image/qpnghandler.cpp
index dc54313..935aba0 100644
--- a/src/gui/image/qpnghandler.cpp
+++ b/src/gui/image/qpnghandler.cpp
@@ -678,41 +678,19 @@ bool QPNGImageWriter::writeImage(const QImage& image, int off_x, int off_y)
     return writeImage(image, -1, QString(), off_x, off_y);
 }
 
-bool Q_INTERNAL_WIN_NO_THROW QPNGImageWriter::writeImage(const QImage& image_in, int quality_in, const QString &description,
+bool Q_INTERNAL_WIN_NO_THROW QPNGImageWriter::writeImage(const QImage& image, int quality_in, const QString &description,
                                  int off_x_in, int off_y_in)
 {
 #ifdef QT_NO_IMAGE_TEXT
     Q_UNUSED(description);
 #endif
 
-    QImage image;
-    switch (image_in.format()) {
-    case QImage::Format_ARGB32_Premultiplied:
-    case QImage::Format_ARGB4444_Premultiplied:
-    case QImage::Format_ARGB8555_Premultiplied:
-    case QImage::Format_ARGB8565_Premultiplied:
-    case QImage::Format_ARGB6666_Premultiplied:
-        image = image_in.convertToFormat(QImage::Format_ARGB32);
-        break;
-    case QImage::Format_RGB16:
-    case QImage::Format_RGB444:
-    case QImage::Format_RGB555:
-    case QImage::Format_RGB666:
-    case QImage::Format_RGB888:
-        image = image_in.convertToFormat(QImage::Format_RGB32);
-        break;
-    default:
-        image = image_in;
-        break;
-    }
-
     QPoint offset = image.offset();
     int off_x = off_x_in + offset.x();
     int off_y = off_y_in + offset.y();
 
     png_structp png_ptr;
     png_infop info_ptr;
-    png_bytep* row_pointers;
 
     png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING,0,0,0);
     if (!png_ptr) {
@@ -743,13 +721,18 @@ bool Q_INTERNAL_WIN_NO_THROW QPNGImageWriter::writeImage(const QImage& image_in,
 
     png_set_write_fn(png_ptr, (void*)this, qpiw_write_fn, qpiw_flush_fn);
 
+
+    int color_type = 0;
+    if (image.colorCount())
+        color_type = PNG_COLOR_TYPE_PALETTE;
+    else if (image.hasAlphaChannel())
+        color_type = PNG_COLOR_TYPE_RGB_ALPHA;
+    else
+        color_type = PNG_COLOR_TYPE_RGB;
+
     png_set_IHDR(png_ptr, info_ptr, image.width(), image.height(),
-        image.depth() == 1 ? 1 : 8 /* per channel */,
-        image.depth() == 32
-            ? image.format() == QImage::Format_RGB32
-                ? PNG_COLOR_TYPE_RGB
-                : PNG_COLOR_TYPE_RGB_ALPHA
-            : PNG_COLOR_TYPE_PALETTE, 0, 0, 0);  // also sets #channels
+                 image.depth() == 1 ? 1 : 8, // per channel
+                 color_type, 0, 0, 0);       // sets #channels
 
     if (gamma != 0.0) {
         png_set_gAMA(png_ptr, info_ptr, 1.0/gamma);
@@ -794,8 +777,9 @@ bool Q_INTERNAL_WIN_NO_THROW QPNGImageWriter::writeImage(const QImage& image_in,
         png_set_swap_alpha(png_ptr);
     }
 
-    // Qt==ARGB==Big(ARGB)==Little(BGRA)
-    if (QSysInfo::ByteOrder == QSysInfo::LittleEndian) {
+    // Qt==ARGB==Big(ARGB)==Little(BGRA). But RGB888 is RGB regardless
+    if (QSysInfo::ByteOrder == QSysInfo::LittleEndian
+        && image.format() != QImage::Format_RGB888) {
         png_set_bgr(png_ptr);
     }
 
@@ -820,7 +804,7 @@ bool Q_INTERNAL_WIN_NO_THROW QPNGImageWriter::writeImage(const QImage& image_in,
     if (image.depth() != 1)
         png_set_packing(png_ptr);
 
-    if (image.format() == QImage::Format_RGB32)
+    if (color_type == PNG_COLOR_TYPE_RGB && image.format() != QImage::Format_RGB888)
         png_set_filler(png_ptr, 0,
             QSysInfo::ByteOrder == QSysInfo::BigEndian ?
                 PNG_FILLER_BEFORE : PNG_FILLER_AFTER);
@@ -841,22 +825,36 @@ bool Q_INTERNAL_WIN_NO_THROW QPNGImageWriter::writeImage(const QImage& image_in,
         png_write_chunk(png_ptr, (png_byte*)"gIFg", data, 4);
     }
 
-    png_uint_32 width;
-    png_uint_32 height;
-    int bit_depth;
-    int color_type;
-    png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
-        0, 0, 0);
-
-    const uchar *data = (static_cast<const QImage *>(&image))->bits();
-    int bpl = image.bytesPerLine();
-    row_pointers = new png_bytep[height];
-    uint y;
-    for (y=0; y<height; y++) {
-        row_pointers[y] = (png_bytep)(data + y * bpl);
+    int height = image.height();
+    int width = image.width();
+    switch (image.format()) {
+    case QImage::Format_Mono:
+    case QImage::Format_MonoLSB:
+    case QImage::Format_Indexed8:
+    case QImage::Format_RGB32:
+    case QImage::Format_ARGB32:
+    case QImage::Format_RGB888:
+        {
+            png_bytep* row_pointers = new png_bytep[height];
+            for (int y=0; y<height; y++)
+                row_pointers[y] = (png_bytep)image.constScanLine(y);
+            png_write_image(png_ptr, row_pointers);
+            delete [] row_pointers;
+        }
+        break;
+    default:
+        {
+            QImage::Format fmt = image.hasAlphaChannel() ? QImage::Format_ARGB32 : QImage::Format_RGB32;
+            QImage row;
+            png_bytep row_pointers[1];
+            for (int y=0; y<height; y++) {
+                row = image.copy(0, y, width, 1).convertToFormat(fmt);
+                row_pointers[0] = png_bytep(row.constScanLine(0));
+                png_write_rows(png_ptr, row_pointers, 1);
+            }
+        }
+        break;
     }
-    png_write_image(png_ptr, row_pointers);
-    delete [] row_pointers;
 
     png_write_end(png_ptr, info_ptr);
     frames_written++;
diff --git a/src/gui/painting/qgrayraster.c b/src/gui/painting/qgrayraster.c
index d0e25a9..ec9ebeb 100644
--- a/src/gui/painting/qgrayraster.c
+++ b/src/gui/painting/qgrayraster.c
@@ -325,6 +325,7 @@
   {
     void*    buffer;
     long     buffer_size;
+    long     buffer_allocated_size;
     int      band_size;
     void*    memory;
     PWorker  worker;
@@ -1791,7 +1792,7 @@
     // If raster object and raster buffer are allocated, but
     // raster size isn't of the minimum size, indicate out of
     // memory.
-    if (raster && raster->buffer && raster->buffer_size < MINIMUM_POOL_SIZE )
+    if (raster->buffer_allocated_size < MINIMUM_POOL_SIZE )
       return ErrRaster_OutOfMemory;
 
     /* return immediately if the outline is empty */
@@ -1930,6 +1931,7 @@
         rast->buffer_size = 0;
         rast->worker      = NULL;
       }
+      rast->buffer_allocated_size = pool_size;
     }
   }
 
diff --git a/src/gui/painting/qpaintengineex.cpp b/src/gui/painting/qpaintengineex.cpp
index 1e857e4..c1e3d66 100644
--- a/src/gui/painting/qpaintengineex.cpp
+++ b/src/gui/painting/qpaintengineex.cpp
@@ -517,7 +517,7 @@ void QPaintEngineEx::stroke(const QVectorPath &path, const QPen &pen)
             QPainterPath painterPath = state()->matrix.map(path.convertToPainterPath());
             d->activeStroker->strokePath(painterPath, d->strokeHandler, QTransform());
         } else {
-            d->activeStroker->setCurveThresholdFromTransform(state()->matrix);
+            d->activeStroker->setCurveThresholdFromTransform(QTransform());
             d->activeStroker->begin(d->strokeHandler);
             if (types) {
                 while (points < lastPoint) {
diff --git a/src/gui/painting/qpainter.cpp b/src/gui/painting/qpainter.cpp
index 1402b44..b0ca6ed 100644
--- a/src/gui/painting/qpainter.cpp
+++ b/src/gui/painting/qpainter.cpp
@@ -6311,7 +6311,7 @@ void QPainter::drawText(const QRectF &r, int flags, const QString &str, QRectF *
 
     By default, QPainter draws text anti-aliased.
 
-    \note The y-position is used as the baseline of the font.
+    \note The y-position is used as the top of the font.
 
     \sa Qt::AlignmentFlag, Qt::TextFlag
 */
diff --git a/src/gui/painting/qrasterdefs_p.h b/src/gui/painting/qrasterdefs_p.h
index 4131e4b..f6339ed 100644
--- a/src/gui/painting/qrasterdefs_p.h
+++ b/src/gui/painting/qrasterdefs_p.h
@@ -100,7 +100,7 @@ QT_FT_BEGIN_HEADER
   /*    distances in integer font units, or 16,16, or 26.6 fixed float     */
   /*    pixel coordinates.                                                 */
   /*                                                                       */
-  typedef signed long  QT_FT_Pos;
+  typedef signed int  QT_FT_Pos;
 
 
   /*************************************************************************/
diff --git a/src/gui/painting/qstroker.cpp b/src/gui/painting/qstroker.cpp
index 9cff339..9decf41 100644
--- a/src/gui/painting/qstroker.cpp
+++ b/src/gui/painting/qstroker.cpp
@@ -190,6 +190,7 @@ static inline qreal adapted_angle_on_x(const QLineF &line)
 QStrokerOps::QStrokerOps()
     : m_elements(0)
     , m_curveThreshold(qt_real_to_fixed(0.25))
+    , m_dashThreshold(qt_real_to_fixed(0.25))
     , m_customData(0)
     , m_moveTo(0)
     , m_lineTo(0)
@@ -243,7 +244,7 @@ void QStrokerOps::strokePath(const QPainterPath &path, void *customData, const Q
     if (path.isEmpty())
         return;
 
-    setCurveThresholdFromTransform(matrix);
+    setCurveThresholdFromTransform(QTransform());
     begin(customData);
     int count = path.elementCount();
     if (matrix.isIdentity()) {
@@ -315,7 +316,7 @@ void QStrokerOps::strokePolygon(const QPointF *points, int pointCount, bool impl
     if (!pointCount)
         return;
 
-    setCurveThresholdFromTransform(matrix);
+    setCurveThresholdFromTransform(QTransform());
     begin(data);
     if (matrix.isIdentity()) {
         moveTo(qt_real_to_fixed(points[0].x()), qt_real_to_fixed(points[0].y()));
@@ -356,7 +357,7 @@ void QStrokerOps::strokeEllipse(const QRectF &rect, void *data, const QTransform
         }
     }
 
-    setCurveThresholdFromTransform(matrix);
+    setCurveThresholdFromTransform(QTransform());
     begin(data);
     moveTo(qt_real_to_fixed(start.x()), qt_real_to_fixed(start.y()));
     for (int i=0; i<12; i+=3) {
@@ -1142,7 +1143,7 @@ void QDashStroker::processCurrentSubpath()
 
     QPainterPath dashPath;
 
-    QSubpathFlatIterator it(&m_elements, m_curveThreshold);
+    QSubpathFlatIterator it(&m_elements, m_dashThreshold);
     qfixed2d prev = it.next();
 
     bool clipping = !m_clip_rect.isEmpty();
diff --git a/src/gui/painting/qstroker_p.h b/src/gui/painting/qstroker_p.h
index d646135..5607a8e 100644
--- a/src/gui/painting/qstroker_p.h
+++ b/src/gui/painting/qstroker_p.h
@@ -168,7 +168,7 @@ public:
     {
         qreal scale;
         qt_scaleForTransform(transform, &scale);
-        setCurveThreshold(scale == 0 ? qreal(0.5) : (qreal(0.5) / scale));
+        m_dashThreshold = scale == 0 ? qreal(0.5) : (qreal(0.5) / scale);
     }
 
     void setCurveThreshold(qfixed threshold) { m_curveThreshold = threshold; }
@@ -184,6 +184,7 @@ protected:
 
     QRectF m_clip_rect;
     qfixed m_curveThreshold;
+    qfixed m_dashThreshold;
 
     void *m_customData;
     qStrokerMoveToHook m_moveTo;
diff --git a/src/opengl/qgl.cpp b/src/opengl/qgl.cpp
index 5c2d948..cb31491 100644
--- a/src/opengl/qgl.cpp
+++ b/src/opengl/qgl.cpp
@@ -515,6 +515,9 @@ QGLFormat::~QGLFormat()
     exchange the screen contents with the buffer. The result is
     flicker-free drawing and often better performance.
 
+    Note that single buffered contexts are currently not supported
+    with EGL.
+
     \sa doubleBuffer(), QGLContext::swapBuffers(),
     QGLWidget::swapBuffers()
 */
@@ -1696,6 +1699,9 @@ void QGLContextPrivate::init(QPaintDevice *dev, const QGLFormat &format)
     workaround_brokenFBOReadBack = false;
     workaroundsCached = false;
 
+    workaround_brokenTextureFromPixmap = false;
+    workaround_brokenTextureFromPixmap_init = false;
+
     for (int i = 0; i < QT_GL_VERTEX_ARRAY_TRACKED_COUNT; ++i)
         vertexAttributeArraysEnabledState[i] = false;
 }
@@ -2578,19 +2584,35 @@ QGLTexture *QGLContextPrivate::bindTexture(const QPixmap &pixmap, GLenum target,
         }
     }
 
-#if defined(Q_WS_X11) && !defined(QT_NO_EGL)
-    // Only try to use texture_from_pixmap under X11/EGL
+#if defined(Q_WS_X11)
+    // Try to use texture_from_pixmap
     const QX11Info *xinfo = qt_x11Info(paintDevice);
     if (pd->classId() == QPixmapData::X11Class && pd->pixelType() == QPixmapData::PixmapType
         && xinfo && xinfo->screen() == pixmap.x11Info().screen()
         && target == GL_TEXTURE_2D
         && QApplication::instance()->thread() == QThread::currentThread())
     {
-        texture = bindTextureFromNativePixmap(const_cast<QPixmap*>(&pixmap), key, options);
-        if (texture) {
-            texture->options |= QGLContext::MemoryManagedBindOption;
-            texture->boundPixmap = pd;
-            boundPixmaps.insert(pd, QPixmap(pixmap));
+        if (!workaround_brokenTextureFromPixmap_init) {
+            workaround_brokenTextureFromPixmap_init = true;
+
+            const QByteArray versionString(reinterpret_cast<const char*>(glGetString(GL_VERSION)));
+            const int pos = versionString.indexOf("NVIDIA ");
+
+            if (pos >= 0) {
+                const QByteArray nvidiaVersionString = versionString.mid(pos + strlen("NVIDIA "));
+
+                if (nvidiaVersionString.startsWith("195") || nvidiaVersionString.startsWith("256"))
+                    workaround_brokenTextureFromPixmap = true;
+            }
+        }
+
+        if (!workaround_brokenTextureFromPixmap) {
+            texture = bindTextureFromNativePixmap(const_cast<QPixmap*>(&pixmap), key, options);
+            if (texture) {
+                texture->options |= QGLContext::MemoryManagedBindOption;
+                texture->boundPixmap = pd;
+                boundPixmaps.insert(pd, QPixmap(pixmap));
+            }
         }
     }
 #endif
diff --git a/src/opengl/qgl_egl.cpp b/src/opengl/qgl_egl.cpp
index ebd1169..c79c4cd 100644
--- a/src/opengl/qgl_egl.cpp
+++ b/src/opengl/qgl_egl.cpp
@@ -143,6 +143,7 @@ void qt_glformat_from_eglconfig(QGLFormat& format, const EGLConfig config)
     format.setRgba(true);            // EGL doesn't support colour index rendering
     format.setStereo(false);         // EGL doesn't support stereo buffers
     format.setAccumBufferSize(0);    // EGL doesn't support accululation buffers
+    format.setDoubleBuffer(true);    // We don't support single buffered EGL contexts
 
     // Clear the EGL error state because some of the above may
     // have errored out because the attribute is not applicable
diff --git a/src/opengl/qgl_p.h b/src/opengl/qgl_p.h
index 73c0d65..78f888a 100644
--- a/src/opengl/qgl_p.h
+++ b/src/opengl/qgl_p.h
@@ -402,6 +402,9 @@ public:
     uint workaround_brokenFBOReadBack : 1;
     uint workaroundsCached : 1;
 
+    uint workaround_brokenTextureFromPixmap : 1;
+    uint workaround_brokenTextureFromPixmap_init : 1;
+
     QPaintDevice *paintDevice;
     QColor transpColor;
     QGLContext *q_ptr;
diff --git a/src/opengl/qglpixelbuffer_win.cpp b/src/opengl/qglpixelbuffer_win.cpp
index 1da0aad..c61d9bf 100644
--- a/src/opengl/qglpixelbuffer_win.cpp
+++ b/src/opengl/qglpixelbuffer_win.cpp
@@ -172,6 +172,10 @@ typedef BOOL (WINAPI * PFNWGLSETPBUFFERATTRIBARBPROC) (HPBUFFERARB hPbuffer, con
 #define WGL_SAMPLES_ARB                0x2042
 #endif
 
+#ifndef GL_SAMPLES_ARB
+#define GL_SAMPLES_ARB 0x80A9
+#endif
+
 QGLFormat pfiToQGLFormat(HDC hdc, int pfi);
 
 static void qt_format_to_attrib_list(bool has_render_texture, const QGLFormat &f, int attribs[])
@@ -258,11 +262,10 @@ bool QGLPixelBufferPrivate::init(const QSize &size, const QGLFormat &f, QGLWidge
 
     dc = wglGetCurrentDC();
     Q_ASSERT(dc);
+    has_render_texture = false;
 
     // sample buffers doesn't work in conjunction with the render_texture extension
-    if (f.sampleBuffers()) {
-        has_render_texture = false;
-    } else {
+    if (!f.sampleBuffers()) {
         PFNWGLGETEXTENSIONSSTRINGARBPROC wglGetExtensionsStringARB =
                 (PFNWGLGETEXTENSIONSSTRINGARBPROC) wglGetProcAddress("wglGetExtensionsStringARB");
 
@@ -303,7 +306,7 @@ bool QGLPixelBufferPrivate::init(const QSize &size, const QGLFormat &f, QGLWidge
 
     pbuf = wglCreatePbufferARB(dc, pixel_format, size.width(), size.height(),
                                has_render_texture ? pb_attribs : 0);
-    if(!pbuf) {
+    if (!pbuf) {
         // try again without the render_texture extension
         pbuf = wglCreatePbufferARB(dc, pixel_format, size.width(), size.height(), 0);
         has_render_texture = false;
@@ -315,12 +318,20 @@ bool QGLPixelBufferPrivate::init(const QSize &size, const QGLFormat &f, QGLWidge
 
     dc = wglGetPbufferDCARB(pbuf);
     ctx = wglCreateContext(dc);
-
     if (!dc || !ctx) {
         qWarning("QGLPixelBuffer: Unable to create pbuffer context - giving up.");
         return false;
     }
 
+    // Explicitly disable the render_texture extension if we have a 
+    // multi-sampled pbuffer context. This seems to be a problem only with 
+    // ATI cards if multi-sampling is forced globally in the driver.
+    wglMakeCurrent(dc, ctx);
+    GLint samples = 0;
+    glGetIntegerv(GL_SAMPLES_ARB, &samples);
+    if (has_render_texture && samples != 0)
+        has_render_texture = false;
+
     HGLRC share_ctx = shareWidget ? shareWidget->d_func()->glcx->d_func()->rc : 0;
     if (share_ctx && !wglShareLists(share_ctx, ctx))
         qWarning("QGLPixelBuffer: Unable to share display lists - with share widget.");
diff --git a/src/opengl/qpaintengine_opengl.cpp b/src/opengl/qpaintengine_opengl.cpp
index 58778ea..2f17aa6 100644
--- a/src/opengl/qpaintengine_opengl.cpp
+++ b/src/opengl/qpaintengine_opengl.cpp
@@ -506,12 +506,12 @@ struct QDrawQueueItem
 
 ////////// GL program cache: start
 
-typedef struct {
+struct GLProgram {
     int brush; // brush index or mask index
     int mode;  // composition mode index
     bool mask;
     GLuint program;
-} GLProgram;
+};
 
 typedef QMultiHash<const QGLContext *, GLProgram> QGLProgramHash;