http://bugs.winehq.org/show_bug.cgi?id=14767
--- Comment #4 from Alexander Sabourenkov screwdriver@lxnt.info 2008-08-15 01:16:56 --- (In reply to comment #3)
They should prove that WGL_SWAP_UNDEFINED_ARB is a reasonable default value.
The value is reasonable because it allows the least amount of assumptions about buffer contents after a swap. Namely, that they're undefined. However, after some discussion in wine-patch list, I revised this patch to use corresponding GLX extension and to use the information in pixel/fbformat selection.
I'm not sure what the best way to right that test is.
I was more concerned with that I found no tests for winex11drv. Having at least one I would have something to model my tests on, but without any I'm at a loss what to do. I need examples.
Slightly offtopic I noticed (on the Mesa list to which I'm not subscribed) that you looked at this missing feature was because you are experiencing image corruption in Sketchup and other OpenGL apps and thought this might be related.
[...]
This same functionality is also needed to render e.g. a glxgears window on one of the faces of a Compiz cube.
Many thanks for the insights. There is something fishy going on with offscreen buffers in free drivers and that would be my next area of investigation. Again, many thanks for this most informative comment.