It is not transparent if applications must opt into using it. Please go ask distributions to pick this up; we aren't going to do it without the legal issues being cleared up. Sending from a mobile, pardon my terseness. ~ C. <div class="gmail_quote">On Aug 8, 2011 6:12 AM, "Rudolf Polzer" <<a href="mailto:divverent@xonotic.org">divverent@xonotic.org</a>> wrote: > On Mon, Aug 08, 2011 at 05:49:09AM -0700, Jose Fonseca wrote: >> ----- Original Message ----- >> > The suggestion however is to include a S2TC-like method with Mesa, to >> > basically >> > make sure that in the long run NO distro has no support for S3TC >> > uploading, >> > without requiring an extra decision in each distro. >> >> I wouldn't oppose bundling S2TC for software renderers, but enabling S3TC decompression on hardware is an orthogonal matter, which depends on the licensing terms between the IHV and S3. >> >> If you wanna fix this, convince IHVs to fully license the S3TC use in their hardware for Linux. So far the only IHV that _seems_ to have such wide cross-OS license is NVIDIA. >> >> I think it would be good to add a FAQ about this in the docs. But I'm done with this stupid thread. I'll enjoy my vacation and stop wasting time with this nonsense. > > In other words: you want the EXISTING support in Mesa to upload S3TC compressed > textures (pre-compressed, not runtime compressed) to the hardware removed. > > It is the driconf option "Enable S3TC texture compression even if software > support is not available" ("force_s3tc_enable" in the configuration file or > environment). > > There is already existing games that use this method to silently enable > precompressed texture even when no libtxc_dxtn library is available: > > <a href="http://trac.wildfiregames.com/ticket/575">http://trac.wildfiregames.com/ticket/575</a> > > So effectively, Mesa already does this. If you were right with your opinion, > this would mean Mesa is ALREADY violating the patent, because any game can > set that environment variable and thus TRANSPARENTLY use S3TC, without the > user being aware that the patented technology is being used. And then I would > ask how it is any MORE illegal if a distro bundles the S2TC lib, and thus > S3TC upload is available WITHOUT setting force_s3tc_enable. > > Summarizing: in the EXISTING code, it's already possible for any application to > enable S3TC decompression. Just enable force_s3tc_enable before initializing > OpenGL. So it is available, just by a "different API" than the one in the > OpenGL extension spec (due to an extra putenv() call being required). Including > S2TC, and thus enabling compressed texture upload by default, only changes the > API by which this functionality is enabled to the standard OpenGL one (without > the putenv() call). > > Best regards, > > Rudolf Polzer > _______________________________________________ > mesa-dev mailing list > <a href="mailto:mesa-dev@lists.freedesktop.org">mesa-dev@lists.freedesktop.org</a> > <a href="http://lists.freedesktop.org/mailman/listinfo/mesa-dev">http://lists.freedesktop.org/mailman/listinfo/mesa-dev</a> </div>