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Use VBO in Heightmaps?

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Hi, Should I use VBOs and push my terrain''s vertices to my video card, knowing that I do frustum culling on my quadtree everytime camera moves? Is it wise to use VBO or not? Thanks.

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i''m new to VBO and don''t really know fully when to use it and when not to use it...

thanks.

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im confused: what would the culling have to do with vbo? culling hopefully doesnt require touching the data in the vbo and the only "problem" i could see is that after culling you skip some of the data in the vbo. or is the terrain so huge, that it takes up most of the video memory while only small parts of it are really visible?

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yes, if i cull away the uneeded polygons and then push the vertices that is inside frustum to video card (through vbo), is that the way to go?

or do i scrap usage of vbo entirely? ''cause in quadtree subdivision, i check for which subtree is visible (inside frustum), and then those inside frustum are the only vertices rendered (which i was thinking of using vbo on them)...

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I think it''s common to have all the vertices in VRAM all the time if the terrain is relatively small. When a part of the terrain is culled, you just don''t tell the GPU to draw it.

Simplistic example: if you have a 256x256 terrain, you could divide that into a number of 32x32 chunks which are leaves in your quadtree. Each one has its own VBO. When you do frustum-culling you''re simply deciding which ones you''re drawing, and not transferring any data to the GPU.

If you need deformable terrain, or large area that can''t fit in VRAM at once, you can still use VBO. You just need to "re-upload" any part of terrain when it changes or when it comes into view. Unless your VBO is changing every frame, this will still have a performance advantage over regular vertex arrays.

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