Merge remote-tracking branch 'origin/5.13' into dev

Change-Id: I99a27f9a0402e1ccad45a2d062d784f8d9a08dd3

4 files changed, 41 insertions, 13 deletions

diff --git a/src/gui/image/qimage.cpp b/src/gui/image/qimage.cpp
index a6ac3bc333..8b2db6d346 100644
--- a/src/gui/image/qimage.cpp
+++ b/src/gui/image/qimage.cpp
@@ -1094,16 +1094,32 @@ void QImage::detach()
 }
 
 
-static void copyMetadata(QImageData *dst, const QImageData *src)
+static void copyPhysicalMetadata(QImageData *dst, const QImageData *src)
 {
-    // Doesn't copy colortable and alpha_clut, or offset.
     dst->dpmx = src->dpmx;
     dst->dpmy = src->dpmy;
     dst->devicePixelRatio = src->devicePixelRatio;
+}
+
+static void copyMetadata(QImageData *dst, const QImageData *src)
+{
+    // Doesn't copy colortable and alpha_clut, or offset.
+    copyPhysicalMetadata(dst, src);
     dst->text = src->text;
     dst->colorSpace = src->colorSpace;
 }
 
+static void copyMetadata(QImage *dst, const QImage &src)
+{
+    dst->setDotsPerMeterX(src.dotsPerMeterX());
+    dst->setDotsPerMeterY(src.dotsPerMeterY());
+    dst->setDevicePixelRatio(src.devicePixelRatio());
+    const auto textKeys = src.textKeys();
+    for (const auto &key: textKeys)
+        dst->setText(key, src.text(key));
+
+}
+
 /*!
     \fn QImage QImage::copy(int x, int y, int width, int height) const
     \overload
@@ -2955,8 +2971,10 @@ QImage QImage::createAlphaMask(Qt::ImageConversionFlags flags) const
     }
 
     QImage mask(d->width, d->height, Format_MonoLSB);
-    if (!mask.isNull())
+    if (!mask.isNull()) {
         dither_to_Mono(mask.d, d, flags, true);
+        copyPhysicalMetadata(mask.d, d);
+    }
     return mask;
 }
 
@@ -3074,6 +3092,7 @@ QImage QImage::createHeuristicMask(bool clipTight) const
 
 #undef PIX
 
+    copyPhysicalMetadata(m.d, d);
     return m;
 }
 #endif //QT_NO_IMAGE_HEURISTIC_MASK
@@ -3117,6 +3136,8 @@ QImage QImage::createMaskFromColor(QRgb color, Qt::MaskMode mode) const
     }
     if  (mode == Qt::MaskOutColor)
         maskImage.invertPixels();
+
+    copyPhysicalMetadata(maskImage.d, d);
     return maskImage;
 }
 
@@ -4688,8 +4709,7 @@ QImage QImage::smoothScaled(int w, int h) const {
 static QImage rotated90(const QImage &image)
 {
     QImage out(image.height(), image.width(), image.format());
-    out.setDotsPerMeterX(image.dotsPerMeterY());
-    out.setDotsPerMeterY(image.dotsPerMeterX());
+    copyMetadata(&out, image);
     if (image.colorCount() > 0)
         out.setColorTable(image.colorTable());
     int w = image.width();
@@ -4717,8 +4737,7 @@ static QImage rotated180(const QImage &image)
         return image.mirrored(true, true);
 
     QImage out(image.width(), image.height(), image.format());
-    out.setDotsPerMeterX(image.dotsPerMeterY());
-    out.setDotsPerMeterY(image.dotsPerMeterX());
+    copyMetadata(&out, image);
     if (image.colorCount() > 0)
         out.setColorTable(image.colorTable());
     int w = image.width();
@@ -4730,8 +4749,7 @@ static QImage rotated180(const QImage &image)
 static QImage rotated270(const QImage &image)
 {
     QImage out(image.height(), image.width(), image.format());
-    out.setDotsPerMeterX(image.dotsPerMeterY());
-    out.setDotsPerMeterY(image.dotsPerMeterX());
+    copyMetadata(&out, image);
     if (image.colorCount() > 0)
         out.setColorTable(image.colorTable());
     int w = image.width();
diff --git a/src/gui/image/qplatformpixmap.cpp b/src/gui/image/qplatformpixmap.cpp
index 2209c3de4d..a2e01147c4 100644
--- a/src/gui/image/qplatformpixmap.cpp
+++ b/src/gui/image/qplatformpixmap.cpp
@@ -178,6 +178,7 @@ QBitmap QPlatformPixmap::mask() const
     if (mask.isNull()) // allocation failed
         return QBitmap();
 
+    mask.setDevicePixelRatio(devicePixelRatio());
     mask.setColorCount(2);
     mask.setColor(0, QColor(Qt::color0).rgba());
     mask.setColor(1, QColor(Qt::color1).rgba());
diff --git a/src/gui/painting/qbrush.cpp b/src/gui/painting/qbrush.cpp
index abfa8d41bb..ed575abf54 100644
--- a/src/gui/painting/qbrush.cpp
+++ b/src/gui/painting/qbrush.cpp
@@ -545,9 +545,11 @@ QBrush::QBrush(const QBrush &other)
 */
 QBrush::QBrush(const QGradient &gradient)
 {
-    Q_ASSERT_X(gradient.type() != QGradient::NoGradient, "QBrush::QBrush",
-               "QGradient should not be used directly, use the linear, radial\n"
-               "or conical gradients instead");
+    if (Q_UNLIKELY(gradient.type() == QGradient::NoGradient)) {
+        d.reset(nullBrushInstance());
+        d->ref.ref();
+        return;
+    }
 
     const Qt::BrushStyle enum_table[] = {
         Qt::LinearGradientPattern,
@@ -1376,8 +1378,10 @@ QGradient::QGradient(Preset preset)
         }();
 
         const QJsonValue presetData = jsonPresets[preset - 1];
-        if (!presetData.isObject())
+        if (!presetData.isObject()) {
+            qWarning("QGradient: Undefined preset %i", preset);
             return;
+        }
 
         m_type = LinearGradient;
         setCoordinateMode(ObjectMode);
diff --git a/src/gui/painting/qplatformbackingstore.cpp b/src/gui/painting/qplatformbackingstore.cpp
index afb4613ba5..c71d82546a 100644
--- a/src/gui/painting/qplatformbackingstore.cpp
+++ b/src/gui/painting/qplatformbackingstore.cpp
@@ -446,6 +446,11 @@ void QPlatformBackingStore::composeAndFlush(QWindow *window, const QRegion &regi
             d_ptr->blitter->setRedBlueSwizzle(false);
     }
 
+    // There is no way to tell if the OpenGL-rendered content is premultiplied or not.
+    // For compatibility, assume that it is not, and use normal alpha blend always.
+    if (d_ptr->premultiplied)
+        funcs->glBlendFuncSeparate(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA, GL_ONE, GL_ONE);
+
     // Textures for renderToTexture widgets that have WA_AlwaysStackOnTop set.
     for (int i = 0; i < textures->count(); ++i) {
         if (textures->flags(i).testFlag(QPlatformTextureList::StacksOnTop))