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Raptor

Vertex Buffers SUCK :(

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hi, i just converted the Xfile sample to use vertex buffers for rendering. this has in fact slowed down the frame rate (from 67fps to 45fps & 105fps to 65fps). I have added the vb code from the Vertex buffer sample (flag sample). The object is rendered properly, implies , the vb is filled properly. Why the hell is it slow????? i have the code and exe up here.... VertexBuffer Code & EXE Original Code & EXE thnx in advance, Edited by - Raptor on 10/31/00 1:21:52 PM

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Also.. and I''m not sure if this is related to your problem, but its worth noting....

If you have a fast CPU, like a mid to high-end P3, with a TnL card like the GeForce, in many instances you will take a frame rate hit when using hardware TnL as opposed to doing it on the CPU.

This is especially true with programs that do nothing at all except 3D rendering (no AI, no physics, no complex game logic, etc). Hardware TnL doesn''t guarantee that the TnL stage will be faster when executed on the video card...it just guarantees that some of the processing will be offloaded from the CPU to allow it to focus on other things.

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The problem is very obvious. You are allways creating vertex buffer only with D3DVBCAPS_DONOTCLIP. If you are running on a non hardware t&l graphics card, you should (must) add D3DVBCAPS_SYSTEMMEMORY and D3DVBCAPS_WRITEONLY caps. But if you are running on a hardware t&l card, you should add D3DVBCAPS_WRITEONLY. If you don''t put D3DVBCAPS_SYSTEMMEMORY when you are in software t&l mode the vertex buffer will be placed in AGP memory (slow). If you put D3DVBCAPS_SYSTEMMEMORY flag when you are in hardware t&l mode vb will be placed in system memory (very slow).

gmcbay: even if you are doing only rendering, even then P3 overclocked to 1GHz won''t catch GeForce or Radeon. Of course if you are using vertex buffers in the right way...

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