RE: [Algorithms] portal engines in outdoor environments

[Bernd K. <bk...@lo...>]

John Ratcliff writes:
 > If you had the ability to ask questions of the zbuffer like "is this
 > bounding volume visable?" (yes/no) in an extremely high speed fashion then
 > you could do gross culling on an object by object basis using the zbuffer
 > contents during the render stage.  Some of the old spanbuffer software
 > renderers could do this, because it was a fairly cheap question to ask,
 > especially relative to the time it took to software render an entire 3d
 > model.
 > 
 > But, since you can't ask zbuffers these kinds of questions it's a moot
 > point.


http://oss.sgi.com/projects/ogl-sample/registry/HP/occlusion_test.txt

Brian Paul mentioned that he is going to add that to Mesa
using the Glide GR_STATS counters. I have no idea which Win32
drivers offer this extension.


                                                b.