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Mars_999
08-17-2006, 05:02 AM
I am trying to get my terrain mesh to render with unsigned short instead of unsigned long for my index buffer. Problem is I want to render 513x513 or larger meshes. I am using culling to eliminate polygons not in view. Issue is with a unsigned short you can only hold values up to 65k. I been told you can use the same IBO to render the whole terrain? Well only way I see that is using many VBO's to hold the terrain data broken down into x amount of patches I have for my mesh? Unless I am seeing this incorrectly please advise. Thanks

08-17-2006, 07:10 PM
are you using LOD? if so what flavor? how big? doing physics? dynamically morphing? etc, etc, etc?

the only way to know for sure is to carefully measure performance under your particular conditions. experiment, and read the IHV white papers on performance for a definitive discussion.

hth

Mars_999
08-17-2006, 08:47 PM
NO LOD. 513x513 with 33x33 patches, using View Frutsum culling, no dynamic mesh

08-17-2006, 11:15 PM
ok. so what's your framerate? what's your framerate if you use 64x64 patches? get the idea? keep changing your patch size to find that sweet spot. (a careful reader of the performance white papers might not have to guess too much, but guessing can be more fun.)

08-17-2006, 11:19 PM
oh, and i suggest that you use lod, for what it's worth ;)

hth