[Qemu-devel] Re: [PATCH] Use opaque alpha channel to support Xgl

[Christian Walther]

Anthony Liguori wrote:

> I really don't like this patch as it seems like a hack but I couldn't
> figure out a way to differentiate in SDL between a 24-bit depth with
> a 32-bit pixel width (which is a common, non-alpha format) and a true
> 32 bit depth with an alpha channel.

Check SDL_Surface->format.Amask (see 
http://www.libsdl.org/cgi/docwiki.cgi/SDL_5fPixelFormat).

> Hopefully, this will be fixed in future versions of SDL.

I'm not convinced there's something to fix in SDL rather than Qemu (but 
I'm not familiar with the issue), but if there is, please post this on 
the SDL mailing list (address@hidden, 
http://news.gmane.org/gmane.comp.lib.sdl).

 -Christian