I’m working on a project for my masters degree. I need to do some
volume visualization of data, and the best way to do it is to use 3d textures.
First I tried the example program from the Red Book. It is VERY slow (maybe 1
frame every few seconds), although it seems to work. I also tried the siggraph '99
example - vol3dtex. It displays a skull … also very slow. The vol2dtex works
great, but of course this is not what I need to do. I guess I would assume that 3d
texturemaps are not supported by Nvidia on TNT2 under linux, except that I had
heard that Quake III uses 3d textures for lightmaps. I have quake III on this
machine, and it runs great (with lightmaps).
If anyone has any idea about what I (and these demos) may be doing wrong, or if
you need more info to help, please either respond here or email me at wade@pacific.mps.ohio-state.edu
after you have skinned your volumetric data you could create the correct 2D textures into the application, then use opengl to render the whole thing without 3D texturing.
Make sure that there are no old Mesa libGL.so libs left laying around. I was getting great fullscreen performance but crappy windowed performance. Then, I noticed I had some old MesaGL libGL.so libs in /usr/lib. I replaced them with nvidia libGL.so, and that fixed it. I was getting incredible windowed framerates there on after.
About using 2d texturemaps - I have thought about it, and if I wanted the 2d textured polys to always face the user, I would have to figure out a new intersection of them with the 3d data each frame - basically software 3d texturemapping. I probably wouldn’t be able to do that faster than what it is now. I could just texture the polys in a fixed way, but then it looks bad (invisible) edge on.
About old libs - I checked /usr/lib/, /usr/local/lib, and of course /usr/X11R6/lib and there are no old libGL’s. Also, I’ve compiled other programs with what is basically the exact same Makefile, and they are accelerated fine.
If anyone has a successfully accelerated app using 3d texture maps, please let me know your hardware and what program you used.