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BK
11-15-2000, 11:22 PM
A while ago I asked something about impementing a texture caching system and the advise was to use glTexSubImage2D(...) to put the replacement texture to the driver.

For compressed textures the equivilent is glTexCompressedSubImage2D() (thats probably wrong but I'm sure you get the idea).

The question is, since texture compression may result in a different footprint, isn't it possible that the target texture object might need to be resized? Or are the compression formats constant ratio.

Or worse since the Tex..Subimage implies that only part of the texture can be updated, would the texture(s) need to be uncompressed, combined and then recompressed?

I havn't done anything with it yet, but it got me curious... Perhaps I'm thinking too much http://www.opengl.org/discussion_boards/ubb/smile.gif


I havn't done anything with this yet, but I was

mcraighead
11-16-2000, 10:32 AM
All current texture compression formats have a fixed compression ratio. It's too difficult to implement any other way in HW.

- Matt