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View Full Version : NPOT DXT1 textures with borders?



andras
03-09-2006, 01:47 PM
Does DXT1 compression support NPOT textures and/or borders? I know that DXT1 compresses 4x4 chunks, but in theory, you could still use it for arbitrary sized textures, by clamping the values to the edge. Also, what if I make a 254x254 texture with borders (totals 256x256)? Can I compress that using DXT1?

Thanks,

Andras

BTW: Is it just me, or did the entire OpenGL server slow down, since this forum update??

Brolingstanz
03-11-2006, 06:39 PM
What if anything does the spec say? I haven't gotten around to it yet.

D3D9 has very heavy restrictions on NPOT textures: No mips, No borders, Clamp wrap only, No DXT1-5.

P.S. It's not just you. It took me 2 minutes just to log in. Maybe they need to give that old server in the broom closet a good talking to... perhaps a bit more.

andras
03-12-2006, 10:28 AM
Well, the OpenGL spec only says that a compressed format might not support borders, but that's not very helpful. Looking at the DXT1 specs, it only specifies how the 4x4 chunks are compressed, but I guess it's implementation dependent how a specific driver handles textures with sizes not dividable by 4.. Heh, I guess I can just give it a try, and see what happens..