summaryrefslogtreecommitdiffstats
path: root/src/widgets/kernel
diff options
context:
space:
mode:
authorHolger Hans Peter Freyther <holger@moiji-mobile.com>2012-04-02 11:59:04 +0200
committerQt by Nokia <qt-info@nokia.com>2012-04-15 06:14:00 +0200
commit83fc52e3b4005d946c731577f8f49becae948c39 (patch)
tree180ff69aae6462273a79585d7da5ed4a1b19b747 /src/widgets/kernel
parent5cb2fbe088ee5b15c2a35ba175e3c39a2fac5c03 (diff)
widgets: Fix painting to a fully transparent top level widget
QWS used to have a line to change the composite mode from SourceOver to Source for the top level widget. This wasn't used with QPA and I removed the internal DontSetCompositionMode in qtbase. It turns out that the QWS way is the most efficient one to initialize the background of the widget. The alternative is to have the QPlatformBackingStore::beginPaint always clear the entire to be painted area and then paint the background of the widget. The difference of painting each pixel once or twice is noticable on embedded platforms and in the range of one to two fps. Reproduce the issue with: echo "QWidget {background: transparent}" > style.css ./examples/widgets/wiggly/wiggly -stylesheet style.css Task-number: QTBUG-24526 Change-Id: Ica4c980bb3bf6eb87ddb5b510ac7493292d01543 Reviewed-by: Samuel Rødal <samuel.rodal@nokia.com> Reviewed-by: Girish Ramakrishnan <girish.1.ramakrishnan@nokia.com>
Diffstat (limited to 'src/widgets/kernel')
-rw-r--r--src/widgets/kernel/qwidget.cpp12
-rw-r--r--src/widgets/kernel/qwidget_p.h3
2 files changed, 13 insertions, 2 deletions
diff --git a/src/widgets/kernel/qwidget.cpp b/src/widgets/kernel/qwidget.cpp
index f02a67d9ea..662c9b7403 100644
--- a/src/widgets/kernel/qwidget.cpp
+++ b/src/widgets/kernel/qwidget.cpp
@@ -2137,7 +2137,15 @@ void QWidgetPrivate::paintBackground(QPainter *painter, const QRegion &rgn, int
if ((flags & DrawAsRoot) && !(q->autoFillBackground() && autoFillBrush.isOpaque())) {
const QBrush bg = q->palette().brush(QPalette::Window);
- fillRegion(painter, rgn, bg);
+ if (!(flags & DontSetCompositionMode)) {
+ //copy alpha straight in
+ QPainter::CompositionMode oldMode = painter->compositionMode();
+ painter->setCompositionMode(QPainter::CompositionMode_Source);
+ fillRegion(painter, rgn, bg);
+ painter->setCompositionMode(oldMode);
+ } else {
+ fillRegion(painter, rgn, bg);
+ }
}
if (q->autoFillBackground())
@@ -5229,6 +5237,8 @@ void QWidgetPrivate::render(QPaintDevice *target, const QPoint &targetOffset,
else
flags |= DontSubtractOpaqueChildren;
+ flags |= DontSetCompositionMode;
+
if (target->devType() == QInternal::Printer) {
QPainter p(target);
render_helper(&p, targetOffset, paintRegion, renderFlags);
diff --git a/src/widgets/kernel/qwidget_p.h b/src/widgets/kernel/qwidget_p.h
index 8107b6ca74..d3fcdce6a8 100644
--- a/src/widgets/kernel/qwidget_p.h
+++ b/src/widgets/kernel/qwidget_p.h
@@ -284,7 +284,8 @@ public:
DrawInvisible = 0x08,
DontSubtractOpaqueChildren = 0x10,
DontDrawOpaqueChildren = 0x20,
- DontDrawNativeChildren = 0x40
+ DontDrawNativeChildren = 0x40,
+ DontSetCompositionMode = 0x80
};
enum CloseMode {