On Fri, 2009-01-23 at 08:51 +0100, Michel Dänzer wrote:
> On Thu, 2009-01-22 at 19:52 +0000, Peter Clifton wrote:
> > 
> > The GLXPixmap created to texture from seems to be lacking information
> > about the proper structure and depth of the underlying pixmap data.
> 
> [...]
> 
> > Should the information regarding the structure of the pixmap be stored
> > against the GLXPixmap, or perhaps even the DRI drawable information?
> 
> AFAICT the GLXPixmap should already have the information; compiz sets
> the GLX_TEXTURE_FORMAT_EXT attribute to GLX_TEXTURE_FORMAT_RGBA_EXT for
> depth 32 and GLX_BIND_TO_TEXTURE_RGB_EXT otherwise. I'm not sure if this
> information is accessible from the setTexBuffer hook as it stands
> though.

Those attributes appears dropped on the floor by Mesa. Only the texture
target is saved. (There is a structure field for that, but nowhere to
stash the texture format).

Its interesting that it is up to the caller to tell GLX what texture
format the pixmap should be using.. especially since the X server knows
the pixmap depth.

I did check in compiz, and the GLX_BIND_TO_TEXTURE_RGB_EXT /
GLX_BIND_TO_TEXTURE_RGBA_EXT is being set correctly for the two types of
texture, but from within setTexBuffer.

Unfortunately I've been unable to find the fbconfig used to make the
pixmap from within setTexBuffer (which is what compiz checks to
determine which of the above flags to set). I can get a fbconfig, but it
appears to be different - or at least, I wasn't able to re-derive which
texture format I'm supposed to be using.


-- 
Peter Clifton

Electrical Engineering Division,
Engineering Department,
University of Cambridge,
9, JJ Thomson Avenue,
Cambridge
CB3 0FA

Tel: +44 (0)7729 980173 - (No signal in the lab!)


------------------------------------------------------------------------------
This SF.net email is sponsored by:
SourcForge Community
SourceForge wants to tell your story.
http://p.sf.net/sfu/sf-spreadtheword
_______________________________________________
Mesa3d-dev mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/mesa3d-dev

Reply via email to