View Full Version : S3TC or FXT1 texture compression ?

06-25-2003, 08:06 AM
I saw the DXTC tools on Nvidia's site, but reading further into it, I see you may need a license from S3, Inc. in order to use DDS/DXTC/S3TC compression "outside of a directX application" ie-(read "in opengl")
I'd really like to not have to buy a license to do my compression.

So I looked for Fxt1 information (because it's open source) but I couldn't find too much about it. Has it died off? I managed to find some old source, but all the links to the command line tools and such are broken.

06-25-2003, 11:05 AM
It's pointless to use a (de)compression scheme that's not supported in hardware. If the hw can't directly use the compressed data you lose most of the benefits of compression (lower gfx mem footprint, lower mem bandwidth consumption).

FXT1 was never implemented on anything except the VSA 100 (Voodoo4/5). While the tech does have its merits, it's dead.

Don't go there ...

06-27-2003, 06:18 AM
So then DDS/S3TC is the ONLY way to go?! That's pretty bad if it's the only way to do decent compression. Because it means that DX users have an advantage over opengl users, since they are allowed to use DXTn compression without purchasing a license.

Is there any loopholes that we opengl developers can use to avoid the licening requirement?

Aren't there any open source or opengl alternatives? Or is this not important enough?
Why are there commands like EXT_S3tc_compression (or whatever) in OpenGL if it's a proprietary compression technology?
Thanks in advance!

06-27-2003, 07:42 AM
I don't think YOU have to license the technology. Probably the vendor should.
BTW, S3 is officially dead so, who would manage the thing? VIA?

06-27-2003, 07:54 AM
Thanks Obli, I hope you're right but I really want to verify that..