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[Soeren Sandmann]

Keith Packard wrote:

>The additional motivation for this position is that Mesa cannot today be
>used as a GL-based compositing manager; it has no way of redirecting GL
>rendering to arbitrary off-screen buffers. So, we have no credible free
>software solution which can take advantage of any of the proposed
>changes in any case. And, the changes necessary to make Mesa able to be
>used in a GL-based compositing manager happen to be reasonably well
>associated with the changes needed to make it possible to draw to the
>root window, leading me to conclude that in waiting for Mesa to be able
>to draw to off-screen buffers, we will simultaneously gain the ability
>to draw to the root window, leaving any changes introduced at this time
>dead weight that will exist for time eternal in our code base.
>  
>
I tend to agree, although I am still not convinced that redirected windows
should participate in clipping - automatically compsited windows should 
clip,
but I don't think manually redirected ones should.

However, note that drawing to offscreen buffers is not strictly necessary to
writing a GL based compositing manager. It can just use normal GL double
buffering.


Soren