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Roadkill
09-23-2002, 09:27 PM
Is it just slang for pixel buffer. I've read the spec (at least everything up to pre-fragment stuff) and I haven't seen anything about it.

-Tyler

JML
09-23-2002, 10:12 PM
I have no real experience with them yet, but from what I've seen pbuffers (indeed pixel buffers) are non-visible rendering areas that can be hardware accelerated.

They can be used to generate textures, create visual effects, render scenes that have to be copied to file etc.

The main advantage is that pbuffers are guaranteed to be completely available for rendering, as opposed to the back-buffer that may not be completely available to the application (because other windows may obscure all or part of the OpenGL window etc.)

Pbuffers were first implemented as extensions by various hw manufacturers, that's why most OpenGL documentation doesn't mention them yet. Currently there are several extensions describing the pbuffers: WGL_ARB_pbuffer, GLX_SGIX_pbuffer, WGL_EXT_pbuffer. Check out the extension registry (http://oss.sgi.com/projects/ogl-sample/registry/) for more detail.

HTH

Jean-Marc

Roadkill
09-24-2002, 08:41 AM
Thanks!

bakery2k
09-24-2002, 01:57 PM
I have just posted two projects using pbuffers. They were my first two attempts at using them. They contain a simple pbuffer class which should make it easy to set a pbuffer up.
http://users.ox.ac.uk/~univ1234