(2) Attempting to bind a framebuffer using GL_RGB32F_ARB, and GL_RGBA32F_ARB formats will fail on my hardware (Nvidia GeForce 6800GS) with error GL_FRAMEBUFFER_UNSUPPORTED_EXT, which means the format combination was invalid for implementation-dependent reasons. However, this doesn't make sense, based on information online, which indicates this should work. See: http://www.mathematik.uni-dortmund.de/~goeddeke/gpgpu/tutorial.htm : "Using textures as render targets".... or google. This is a problem, since certain demos which make use of the R32F format won't work with FBOs - but oddly work with pbuffers. See SoftShadowsII: http://www.humus.ca/index.php?page=3D&&start=8 On the other hand I know R16F -> GL_RGB16F works fine, based on 3Dc demo.
I'm seeing in quite a few places that this must be done to fix the issue of floating point textures: GL_TEXTURE_WRAP_S -> GL_CLAMP_TO_EDGE GL_TEXTURE_WRAP_T -> GL_CLAMP_TO_EDGE GL_TEXTURE_MIN -> GL_NEAREST GL_TEXTURE_MAG -> GL_NEAREST
Hmmm.. not quite sure where to change it though..