graw: fix logic error in pixel format selection

The loop to choose a pixel format for the window was incrementing
'i' after we succeeded in creating the window so if we chose format[0]
for graw_create_window_and_screen() we were putting format[1] in
the pipe_resource template for creating the render target.

This only worked because of the order of the elements in the formats[]
array.

The graw_xlib.c code now properly compares the requested gallium pixel
format against the visual's color layout.

Update all the graw demos to fix the off-by-one-i error.

1 files changed, 17 insertions, 3 deletions

diff --git a/src/gallium/targets/graw-xlib/graw_xlib.c b/src/gallium/targets/graw-xlib/graw_xlib.c
index 578086f8f9..b6d798e577 100644
--- a/src/gallium/targets/graw-xlib/graw_xlib.c
+++ b/src/gallium/targets/graw-xlib/graw_xlib.c
@@ -66,9 +66,6 @@ graw_create_window_and_screen( int x,
    root = RootWindow( graw.display, scrnum );
 
 
-   if (format != PIPE_FORMAT_R8G8B8A8_UNORM)
-      goto fail;
-
    if (graw.display == NULL)
       goto fail;
 
@@ -88,6 +85,23 @@ graw_create_window_and_screen( int x,
       exit(1);
    }
 
+   /* See if the requirested pixel format matches the visual */
+   if (visinfo->red_mask == 0xff0000 &&
+       visinfo->green_mask == 0xff00 &&
+       visinfo->blue_mask == 0xff) {
+      if (format != PIPE_FORMAT_B8G8R8A8_UNORM)
+         goto fail;
+   }
+   else if (visinfo->red_mask == 0xff &&
+            visinfo->green_mask == 0xff00 &&
+            visinfo->blue_mask == 0xff0000) {
+      if (format != PIPE_FORMAT_R8G8B8A8_UNORM)
+         goto fail;
+   }
+   else {
+      goto fail;
+   }
+
    /* window attributes */
    attr.background_pixel = 0;
    attr.border_pixel = 0;