[PATCH 1/1] opengl32: Perform cAccumBits filtering if specified in wglChoosePixelFormat().

[chenjiangyi]

From: chenjiangyi

On Windows, if wglChoosePixelFormat specifies cAccumBits, the best matching
PIXELFORMATDESCRIPTOR obtained should contain AccumBits information.
Some industrial software, such as CAD applications, require matching
the AccumBits information.

Signed-off-by: chenjiangyi 
---
 dlls/opengl32/wgl.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/dlls/opengl32/wgl.c b/dlls/opengl32/wgl.c
index b24225684e0..76b452841b1 100644
--- a/dlls/opengl32/wgl.c
+++ b/dlls/opengl32/wgl.c
@@ -145,6 +145,7 @@ INT WINAPI wglChoosePixelFormat(HDC hdc, const PIXELFORMATDESCRIPTOR* ppfd)
     best.cDepthBits = -1;
     best.cStencilBits = -1;
     best.cAuxBuffers = -1;
+    best.cAccumBits = -1;

for (i = 1; i <= count; i++)
     {
@@ -294,6 +295,18 @@ INT WINAPI wglChoosePixelFormat(HDC hdc, const PIXELFORMATDESCRIPTOR* ppfd)
                 continue;
             }
         }
+        if (ppfd->cAccumBits)
+        {
+            if (((ppfd->cAccumBits > best.cAccumBits) && (format.cAccumBits > best.cAccumBits)) ||
+                ((format.cAccumBits >= ppfd->cAccumBits) && (format.cAccumBits < best.cAccumBits)))
+                goto found;
+
+            if (best.cAccumBits != format.cAccumBits)
+            {
+                TRACE( "cAccumBits mismatch for iPixelFormat=%d\n", i );
+                continue;
+            }
+        }
         if (ppfd->dwFlags & PFD_DEPTH_DONTCARE)
         {
             if (format.cDepthBits < best.cDepthBits)