[PATCH 0/4] MR6298: winewayland: Support WGL pbuffers

[Alexandros Frantzis (＠afrantzis)]

EGL Wayland doesn't support pbuffer EGLSurfaces (and it doesn't seem it will ever gain support for them), but we can emulate them in winewayland WGL/OpenGL by using a normal window EGLSurface targeting an unmapped wl_surface. For `wglBindTexImage` we use the same `glCopyTexImage` approach used by winex11 and, like in winex11, our implementation is incomplete (only 2D textures and only from the pbuffer back buffer), but should be a good start.

Please try a few of your (likely) older games that use pbuffers and let me know if you see any issues.

Note: While implementing this I realized that we are missing a `wglGetPixelFormat` implementation, I will provide one in a follow-up MR.