How do I prevent blitting on resize?

[Philius]

Hi there.

Looking at the "overpainting" OpenGL example, when I resize the window, the instructions text gets blitted in the direction of the vertical part of the resize before the widget is repainted.

This happens with the "basicdrawing" example too.
You can see it on the top right hand side - the contents get blitted when you shrink the window from the left.
Then almost immediately the border is then drawn over it.

Is there a way of telling Qt not to blit the old contents when you want to redraw the entire contents of a widget?

I vaguely remember that on Windows there was a window flag you could set to do this.