ARB_texture_compression extension

Calling glTexImage2D with an uncompressed image and a generic compressed internal format, make the texture image be compressed by the GL, if possible. So what happen when this is not possible ? Does GL upload the texture with the associated uncompressed form or does GL do nothing ?


It’s probably driver dependant what it does. My bet is on it doing nothing. Setting an error.

YOU should make sure the extension exists, before passing a compression value over as the internal format, not reply on the driver to fall back to “default” mode if it doesn’t.


When I implemented this ( a while back, hope I remember correctly) I went by

 Compressed textures Will not be stored on error

you should store PREcompiled textures and uncopiled textures on disk
dont do what It lokks like your doing and compress while the program loads.
I know its easyer to code, but it can result in LONG loading times in some cases.

-------- btw ---------
Also Since this is a discussion forum whatch out for bugs with geforce2 and s3tc.
Ive noted that there is a blue tinge when this card uses compressed textures.

I.D. built a work around for quake3 to get around this problem. Any one know what they did to fix the problem???

no, but I know that Serious Sam does too (it’s an addon that you have to execute)…my sugestion: get serious sam test2, and find the script…there should be tip in there