While there is not integrated support for S3 Texture Compression (S3TC) support fully integrated into the Mesa / Gallium3D code-base over patents covering the algorithm, there are Mesa drivers that support hooking into an external S3TC library. This external S3TC support requires setting a special variable in the build process and building the S3TC library (named libtxc_dxtn.so) after obtaining the code from an independent source. This move shifts the legal burden from the Mesa developers and onto the user…
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