Some QWindowSurface implementations might implement flush as a buffer

flip. Such window surfaces therefore destroy the contents during flush.
In order to render correctly on these surfaces, any update, no matter
how small, needs to trigger the entire window to be redrawn.

Auto test included.

Task-number: Relates to QTBUG-9978
Reviewed-by: tom

1 files changed, 2 insertions, 0 deletions

diff --git a/src/gui/painting/qwindowsurface_p.h b/src/gui/painting/qwindowsurface_p.h
index 0a453af..e6ee5f6 100644
--- a/src/gui/painting/qwindowsurface_p.h
+++ b/src/gui/painting/qwindowsurface_p.h
@@ -90,6 +90,7 @@ public:
     inline QRect rect(const QWidget *widget) const;
 
     bool hasStaticContentsSupport() const;
+    bool hasPartialUpdateSupport() const;
 
     void setStaticContents(const QRegion &region);
     QRegion staticContents() const;
@@ -97,6 +98,7 @@ public:
 protected:
     bool hasStaticContents() const;
     void setStaticContentsSupport(bool enable);
+    void setPartialUpdateSupport(bool enable);
 
 private:
     QWindowSurfacePrivate *d_ptr;