[Mesa-dev] Private window system depth/stencil buffers

[Eric Anholt]

We've been talking about doing this for a long time -- ignore the
piece of the GLX spec about clients sharing auxiliary buffers across
address spaces, and just allocate our own buffers.  Ever since HiZ we
think it's probably been broken, and it was probably just going to get
worse with window system MSAA buffers without reams of code for
communicating the state between processes.

This doesn't convert back buffers (we would need a swapbuffers and
copyregion interface that took a BO instead of an attachment point) or
the fake front buffer (I'd really like to bring that into the client,
but that requires new interfaces between the loader and driver so the
driver can implement glXWaitGL/X).

Passed piglit, and I resized a glxgears a bunch, but we know we're
weak on glx testing in piglit.