path: root/src/gui/painting/qpainter.cpp
diff options
authorAllan Sandfeld Jensen <>2016-04-27 11:53:16 +0200
committerAllan Sandfeld Jensen <>2016-05-23 18:21:03 +0000
commit3cae115d6d6e8a1d4d0385e3cde16f59b25acad0 (patch)
treeddb7a083ea0de3d03c308381068ab4b72047f00a /src/gui/painting/qpainter.cpp
parentffd99e1d1803a8b82eab8d8b6c1cd9e58af36ee5 (diff)
Correct compositionMode documentation
Most composition modes require an alpha-channel to be meaningful, but not all, and there is no requirements of specific formats. Change-Id: I11e930ccc07e9ff5df06dbda6745e4afb79f5e08 Reviewed-by: Leena Miettinen <> Reviewed-by: Gunnar Sletta <>
Diffstat (limited to 'src/gui/painting/qpainter.cpp')
1 files changed, 4 insertions, 5 deletions
diff --git a/src/gui/painting/qpainter.cpp b/src/gui/painting/qpainter.cpp
index 1acd84754a..51c0f3e22a 100644
--- a/src/gui/painting/qpainter.cpp
+++ b/src/gui/painting/qpainter.cpp
@@ -2182,11 +2182,10 @@ void QPainter::setBrushOrigin(const QPointF &p)
destination pixel in such a way that the alpha component of the
source defines the translucency of the pixel.
- When the paint device is a QImage, the image format must be set to
- \l {QImage::Format}{Format_ARGB32_Premultiplied} or
- \l {QImage::Format}{Format_ARGB32} for the composition modes to have
- any effect. For performance the premultiplied version is the preferred
- format.
+ Several composition modes require an alpha channel in the source or
+ target images to have an effect. For optimal performance the
+ image format \l {QImage::Format}{Format_ARGB32_Premultiplied} is
+ preferred.
When a composition mode is set it applies to all painting
operator, pens, brushes, gradients and pixmap/image drawing.