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View Full Version : texture repeat slow



soconne
02-09-2004, 05:47 AM
I'm using a Radeon 9800 Pro with a 2.8 Ghz P4 HT and I'm running into a really odd problem.

All I am rendering is a simple cube with a texture map. If the texture is simply tiled across each face of the cube once, everything runs good, meaning fast. But if I tile the texture across each face many times, let's say 20 times per face, then the program slows down by about half the frame rate. Is this normal? Should opengl slow down when you repeat a texture?

ZbuffeR
02-09-2004, 09:06 AM
But if I tile the texture across each face many times, let's say 20 times per face, then the program slows down by about half the frame rate. Is this normal?

If you do not use mipmaps, it is very likely. As the large texture is sampled at 'sparse' locations, it ruins most of the texture cache, and almost forces the card to read 20x20 times your texture.

Mipmaps should help in keeping steady performance, and may even increase it.