S3TC Support Will Land In Mesa Now That The Patent Has Expired
Matt Turner of Intel has sent out a patch this morning, on the S3TC patent expiry date, to add support to mainline Mesa. The code used is what previously lived in its own standalone libtxc_dxtn library.
With the patches, EXT_texture_compress_s3tc and ANGLE_texture_compression_dxt are enabled by default in all supported configurations.
The patches for now can be found on Mesa-dev and will hopefully be merged to mainline in the days ahead for Mesa 17.3.