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tcs
03-07-2000, 10:12 AM
Hi,

I'm doing a large outdoor engine. At first I have rendered my terrain into a single display list.
Since testing the visibility for all triangles of my landscape is to slow, I decided to divide
my landscape into sectors. Each sector is rendered into s displaylist. I have implemented this and
wanted to do the visibility detection. But it seems like this is unnecessary! OpenGL already seems not
to bother with display lists that lie outside the view. My engines runs with 3x the FPS cause the
terrain is clipped by opengl. I'm using the nVidia ICD on a GeForceDDR. Is this behavior to to a fast
cliiping on display lists implementation depend ? Should I rely on it ? Should I code my own alogrithm
to filter out invisible display lists or should I let OpenGL do the work ?

Tim

Gorg
03-07-2000, 10:17 PM
You just felt the GeForce Power!!!! http://www.opengl.org/discussion_boards/ubb/smile.gif

If the display list is too big, some optizimisations by the drivers cannot be done. If you chew it smaller ones it will be much faster.

Don't count on openglClipping, because still all the vertices of your terrain are calculated(it just that GeForce DDR! lucky you http://www.opengl.org/discussion_boards/ubb/smile.gif is fast).

If you do your own visibility, you'll gain more precious fps that can be use for other SFX.

tcs
03-08-2000, 06:21 AM
yes, GeForce rulez ;-))
It just seems that nVidia GL uses some very fast clipping for sorting out complete displaylists. It seems that it calculates a bounding box and test then for visibility. But I'm afraid other implementations dont't do ;-)