Luciano Pinho (lpinho++at++onyx.fe.up.pt)
Thu, 17 Apr 1997 13:03:33 -0700
I'm trying to speed up culling by using geometric coherence.
The scene is a city, so I've defined some strategically placed
oclusion planes that if placed between the camera and an object
will turn it invisible.
There is a pre-processing stage for the determination of the
"shadow" region of each plane for each node.
Than I should modify culling in such a way that after fustrum
culling each 'visible' node would be tested against every oclusion
plane's shadow volume for a more restrictive visibility testing.
The problem is that the culling callback method doesn't seem to work
properly:
1- Should I use pre or post culling?
Pre is before fustrum culling, wich is not what I want,
but Post is done after all the child of the node are
processed, wich seems to be inneficient!
2- I've implemented a simple test callback, but it seems
that it is executed only once for the hole scene.
What I need is a callback that is called for each node,
so that I can do the oclusion tests.
Can anyone help me on this or have any sugestion?
Thank you so much!
--------------------------------------------------------------------------------
Luciano Pinho
FEUP - Engineering at Oporto University, PORTUGAL
lpinho++at++onyx.fe.up.pt
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