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ctoan

OpenGL OpenGL connections

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ctoan    122
Just recently, I''ve been using a DirectX engine I''ve made to program a simple game. Well, I noticed, while adding small effects that require a different DrawIndexedPrimitive(), the frame rate would get cut in half, even though the vertex buffer and index buffer is precomputed. What I want to know is how can OpenGL be so versatile in its method of defining vertices glVertex3f() etc. and still obtain real-time rates? And if anyone knows any optimizations for DirectX that you WON''T read in anyone''s tutorials, PLEASE share! :D Chris Pergrossi < ctoan > My Realm

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By itself a halving of the frame rate doesn''t carry any significance. There''s a huge difference between halving from 1000 to 500 FPS and 100 to 50 (an added 1 ms./f in the first case, 10 ms./f in the second). Halving from 10 FPS to 5 means you added a whopping 100 ms. to the frame time.

Sometimes people get alarmed because their frame rate dropped a massive 500 FPS! And it''s just not a big deal. Using milliseconds per frame instead of frames per second will avoid this kind of misperception.

Also check that you''re not profiling against the debug runtime.

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