On Fri May 8 02:49:55 2026 +0000, Paul Gofman wrote:
Well, it is not quite the case: I think the game would probably be fine with either old or new Windows behaviour (like it was fine on Wine before 'exclusive fullscreen mode' support). The problem is not clipping, the problem is that the rendering to a separate (clipper) window just goes nowhere in exclusive fullscreen mode now. There are various ways to fix it. It seems to me that avoiding using clipper window surface is preferred (and it is orthogonal to old vs new Windows, it is just our internal kitchen how the image gets onscreen). It is not strictly necessary to remove the actual clipping, we could probably keep it and still fix a regression. Although that would need more changes (how the clipping region is got in fullscreen), I'd probably suggest to stick to the new Windows behaviour (well, at least until it breaks something) as it is easier to unit test. Why I think avoiding client window surface is preferred (regardless whether we are going to do clipping or not) is that it is straightforward: rendering in exclusive fullscreen emulates blitting directly to screen buffer. Using another window is less straightforward: it is subject for compositing in principle, that window is not supposed to render on top of everything (would maybe need a special flag for 'exclusive fullscreen' Wine extension). Then, it results in extra GL context, 'client window' on the clipper window, blitting from it in winex11 and all that is easily avoided.
-- https://gitlab.winehq.org/wine/wine/-/merge_requests/10842#note_139180