S3TC Support Will Land In Mesa Now That The Patent Has Expired

[phoronix]

Phoronix: S3TC Support Will Land In Mesa Now That The Patent Has Expired

As mentioned last week, the S3TC patent has now expired. With the S3 Texture Compression no longer encumbered by a patent, support for it is being added to mainline Mesa...

http://www.phoronix.com/scan.php?page=news_item&px=S3TC-For-Mesa-Finally

[Nille_kungen]

I was hoping to see it backported to 17.2 as well.

[MihaiBojescu]

Does this bring any improvements?

[schmidtbag]

Does this affect all GPUs in mesa or just Intel? Either way, I'm excited to see test results of this. Makes me wonder if this will eliminate the performance gap in some tests vs Windows (note I said some).

[oibaf]

This just avoid the need to use the external library, used by many distros (Debian and Ubuntu for sure).
There is also no need in stable mesa release, just use the external library to get the same effect.

[bug77]

This just avoid the need to use the external library, used by many distros (Debian and Ubuntu for sure).
There is also no need in stable mesa release, just use the external library to get the same effect.

True, but at the same time, the less work on packagers, the less potential for bugs

[necrophcodr]

Does this affect all GPUs in mesa or just Intel? Either way, I'm excited to see test results of this. Makes me wonder if this will eliminate the performance gap in some tests vs Windows (note I said some).

Seems to be for all GPUs.

[microcode]

Man, I can't wait for ASTC (ldr at least) to be supported across all major vendors between desktop and embedded.

[oiaohm]

This just avoid the need to use the external library, used by many distros (Debian and Ubuntu for sure).
There is also no need in stable mesa release, just use the external library to get the same effect.

I would not exactly say same effect. Thinking that removing the external library feature end up deleting more code than what is used todo s3tc compression/decompression including a lot of platform dependant code.

Also if you read the bug report this is the first merge there are plans to look to crunch implementation and other things to optimise more that it can be legally worked on mainline. So might be close now in performance in a few releases who knows.

Please note s3tc has higher compression ratios than ASTC because s3tc is a little lossy.

[imirkin]

Please note s3tc has higher compression ratios than ASTC because s3tc is a little lossy.

Huh? S3TC is 16 RGBA texels in 64-bit (DXT1) or 128-bit (DXT3/5). I also think there's a big "*" on the alpha in the 64-bit case in terms of ability to represent various values.

ASTC can go between 16 (ASTC_4x4) to 144 (ASTC_12x12) RGBA texels in 128-bit of data. Of course the quality stinks with 12x12, you get what you paid for at that compression level. Both are lossy.