Re: [PATCH 0/2] MR7780: win32u: Avoid uneeded (and sometimes harmful) RedrawWindow() calls in expose_window_surface().

[Rémi Bernon (＠rbernon)]

> The idea of the region math in winex11.drv:expose_surface() before those changes was that the surface region is subtracted from "to be exposed" region. So resulting region has only the area which is to be exposed but is _not_ covered by the surface.

I don't think this is right or doing anything useful. There is never any part of the window that isn't covered by the surface. And even if there was, redrawing pixels outside of the surface (region) is pointless as they have nowhere to go.