Am Sonntag, 14. Oktober 2007 18:24:42 schrieb Chris Robinson:
With some other fixes, it may work better using pbuffers where there are possibly R32F formats available. Unfortunately, by oversight or design, GL has no renderable single-component formats* so we have to fall back to R32G32B32F, which could be a bit harder on the hardware. Most apps seem to only use it for shadow mapping though, so perhaps using a 32-bit depth texture would work? And maybe use depth textures for R16F as well.
What does a depth texture return for red, green, blue and alpha when sampled by a pixel shader, or a vertex shader via VTF? Does it work with fixed function fragment processing? It may be a workable solution if the returned channels match, since it doesn't have the texture rectangle restriction.