ledogar++at++flanders.mtv.gtegsc.com
Wed, 12 Jul 95 14:26:45 -0700
We've got a similar problem, encapsulating a "live" X pixmap into a pfTexture.
We've had reasonable success on a sw-texmapping Indigo but haven't been able to
get the code running on our Onyx yet.
It seems the Onyx has a facility for "dynamic textures" involving the use of the
FAST_DEFINE token when calling texdef from gl (refer to the texdef man page).
Apparently non-FAST_DEFINE textures are loaded into a secondary CPU memory array
(which the hardware texture memory reads and swaps out to), permitting some
useful effects like mipmapping but causing a delay too large for live video.
FAST_DEFINE tells the hardware to read/swap out to your array directly. The
texture memory can be rapidly updated using subtexload (or perhaps in your case
using fbsubtexload).
However we've encountered two problems:
1) specifying FAST_DEFINE gives us difficult-to-trace seg faults, and
2) Performer has a facility for specifying FAST_DEFINE, but doesn't seem to have
a facility for subtexload (although if we were able to find out the gl "texture
id" of a pfTexture, that would let us use the subtexload directly).
Hope you have better luck!
---Charlie Ledogar
GTE Government Systems
Mountainview, CA
chl2++at++gte.com
This archive was generated by hypermail 2.0b2 on Mon Aug 10 1998 - 17:51:41 PDT