Fixes wrong QPaintEvent::region() in QGLWidget::paintEvent.

QGLWidget does not support partial updates unless the context is
single buffered and auto-fill background is disabled. The problem
was that QPaintEvent::region() returned the requested update region
without taking into account the limitation of QGLWidget. If QGLWidget
doesn't support partial updates, it means everything has to be updated,
and QPaintEvent::region() must return the whole widget rect.

Auto test included.

Task-number: 241785
Reviewed-by: Trond

1 files changed, 4 insertions, 0 deletions

diff --git a/src/opengl/qgl.cpp b/src/opengl/qgl.cpp
index b4a0e5c..8ffee87 100644
--- a/src/opengl/qgl.cpp
+++ b/src/opengl/qgl.cpp
@@ -2398,6 +2398,10 @@ bool QGLContext::create(const QGLContext* shareContext)
         return false;
     reset();
     d->valid = chooseContext(shareContext);
+    if (d->valid && d->paintDevice->devType() == QInternal::Widget) {
+        QWidgetPrivate *wd = qt_widget_private(static_cast<QWidget *>(d->paintDevice));
+        wd->usesDoubleBufferedGLContext = d->glFormat.doubleBuffer();
+    }
     if (d->sharing)  // ok, we managed to share
         qgl_share_reg()->addShare(this, shareContext);
     return d->valid;