Fixed text rendering bug in raster engine when opacity != 1.0.

If opacity is updated independently from the pen properties sometimes
the raster engine's fast_text flag would not be updated correctly,
causing it to use a rendering path which doesn't support alpha.

Reviewed-by: Robin Burchell
Reviewed-by: Andreas Kling

1 files changed, 3 insertions, 1 deletions

diff --git a/src/gui/painting/qpaintengine_raster.cpp b/src/gui/painting/qpaintengine_raster.cpp
index 161ced5..89202ac 100644
--- a/src/gui/painting/qpaintengine_raster.cpp
+++ b/src/gui/painting/qpaintengine_raster.cpp
@@ -875,9 +875,10 @@ void QRasterPaintEngine::updateState()
     if (s->dirty & DirtyTransform)
         updateMatrix(s->matrix);
 
-    if (s->dirty & (DirtyPen|DirtyCompositionMode)) {
+    if (s->dirty & (DirtyPen|DirtyCompositionMode|DirtyOpacity)) {
         const QPainter::CompositionMode mode = s->composition_mode;
         s->flags.fast_text = (s->penData.type == QSpanData::Solid)
+                       && s->intOpacity == 256
                        && (mode == QPainter::CompositionMode_Source
                            || (mode == QPainter::CompositionMode_SourceOver
                                && qAlpha(s->penData.solid.color) == 255));
@@ -901,6 +902,7 @@ void QRasterPaintEngine::opacityChanged()
     s->fillFlags |= DirtyOpacity;
     s->strokeFlags |= DirtyOpacity;
     s->pixmapFlags |= DirtyOpacity;
+    s->dirty |= DirtyOpacity;
     s->intOpacity = (int) (s->opacity * 256);
 }