[Bug 9378] Combat Mission Shock Force DEMO: ' Could not initialize OpenGL graphics.'

https://bugs.winehq.org/show_bug.cgi?id=9378

Alexander Puzankov  changed:

What    |Removed                     |Added
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                 CC|                            |[e-mail]

--- Comment #17 from Alexander Puzankov  ---
Problem is in pixel formats returned by DescribePixelFormat, specifically in
the cAlphaShift field. Combat Mission engine enumerates these until
cAlphaShift=24 is found (amongst other checks), but Wine always sets 0 there.
This patch seems to fix the issue:

--- a/dlls/winex11.drv/opengl.c
+++ b/dlls/winex11.drv/opengl.c
@@ -1725,7 +1725,7 @@ static int glxdrv_wglDescribePixelFormat
     ppfd->cGreenBits = gb;
     ppfd->cGreenShift = bb + ab;
     ppfd->cAlphaBits = ab;
-    ppfd->cAlphaShift = 0;
+    ppfd->cAlphaShift = 24;
   } else {
     ppfd->cRedBits = 0;
     ppfd->cRedShift = 0;

But I'm not entirely sure this doesn't break something else (in other apps), or
is otherwise the correct way.