xserver on OpenGL

[Keith Packard]

Around 12 o'clock on Dec 5, Jon Smirl wrote:

> Is anyone working on getting xserver to run under current X DRI? Both
> Nvidia and ATI proprietary drivers support the needed pbuffers. Doing this
> is pretty much the same work needed to bring xserver up on mesa-solo.

Keith Whitwell expressed an interest to play with this, but of course his 
time is limited.  I think he said he was interested in doing a "real" OpenGL 
back-end which didn't depend on direct frame buffer access.

> Are there still outstanding concerns that framebuffer access is required to
> implement xserver on OpenGL? I though Brian had addressed all of these.

Remember that framebuffer access should largely be seens as an
implementation crutch while GL-based acceleration code is written.  
Without that crutch, it will take a large amount of effort before *any* 
thing appears on the screen.  If you can provide direct access to the 
underlying object buffers for each image, I can get the X server running 
in a few hours.  Then we can share the effort for migrating the X 
operations to GL among many developers.  A working X server is a lot 
easier to hack on than a pile of non-functional code.

>From explorations that Eric Anholt has done in getting Xati running atop 
the DRM, it appears likely that OpenGL will be able to accelerate almost 
every operation in Render quite nicely; if true, we'll be able to get rid 
of the direct frame buffer access without having to fall back to get/put 
pixel operations.

-keith