Add support for setting an opacity mask on QGraphicsOpacityEffect.

Opacity masks enable you to make portions of an element transparent.
More information about opacity masks here:
http://msdn.microsoft.com/en-us/library/ms743320.aspx

Reviewed-by: Samuel

1 files changed, 10 insertions, 0 deletions

diff --git a/doc/src/snippets/code/src_gui_effects_qgraphicseffect.cpp b/doc/src/snippets/code/src_gui_effects_qgraphicseffect.cpp
index 6265c80..152b04f 100644
--- a/doc/src/snippets/code/src_gui_effects_qgraphicseffect.cpp
+++ b/doc/src/snippets/code/src_gui_effects_qgraphicseffect.cpp
@@ -31,3 +31,13 @@ MyGraphicsEffect::draw(QPainter *painter, QGraphicsEffectSource *source)
 }
 //! [1]
 
+//! [2]
+...
+QLinearGradient alphaGradient(rect.topLeft(), rect.bottomLeft());
+alphaGradient.setColorAt(0.0, Qt::transparent);
+alphaGradient.setColorAt(0.5, Qt::black);
+alphaGradient.setColorAt(1.0, Qt::transparent);
+QGraphicsOpacityEffect *effect = new QGraphicsOpacityEffect;
+effect->setOpacityMask(alphaGradient);
+...
+//! [2]