Check this out!

http://hoegsberg.blogspot.com/2007/08/redirected-direct-rendering.html

This is the solution to the GLX direct/indirect rendering conundrum
[which has annoyed me for years].  Dave Airlie et. al. have (alpha
quality for now, but it does work) a zero-copy offscreen pixmap
implementation:  Thus, DRI can render offscreen into EXA-allocated,
TTM-managed buffers.
In freedesktop.org's git, AFAIK, there is relatively mature FreeBSD
code (by Eric Anholt) which could be merged into our tree to support
this.

Unfortunately, I cannot sit at home and work on NetBSD stuff all day.
:(  I will do what I can, but if anyone's interested in working on
this as well (I'm just "cutting my teeth" on this stuff now), please
do let me know.

Regards,

--Blair