[Mesa-dev] [PATCH 00/15] Import libtxc_dxtn's S3TC code into Mesa!

[Emil Velikov]

On 2 October 2017 at 07:59, Matt Turner <mattst88 at gmail.com> wrote:
> The patent on S3TC has now expired! Rejoice!
>
It's time to open that 20 year old bottle of wine ;-)

> This series imports the code from Roland's libtxc_dxtn into Mesa and cleans up
> some mess dealing with the possibility of S3TC not being available.
>
> EXT_texture_compression_s3tc and ANGLE_texture_compression_dxt are now always
> enabled where supported.
>
> Note that I did almost nothing to fix the style of the imported code. Feel free
> to send patches, but I'm not interested in making those changes in this series.
>
Agreed, one could polish at a later stage. Be that coding style or
performance(?).

>
> I also considered using Rich Geldreich's crunch [2], but a few things made be
> choose to start with libtxc_dxtn instead:
>
>    - crunch is written bn C++ and does not look like Mesa code at all.
>
>    - Higher risk. Unknown how it compares to libtxc_dxtn. I can believe
>      libtxc_dxtn does a worse job compressing, but at least we know exactly
>      what we are getting with it.
>
>    - crunch actually does a lot more than just DXT1/a/3/5. Was unclear how
>      separable those pieces were from the rest.
>
Better the devil we know than the one we don't. At least to begin with.

There's a few small suggestions - feel free to take or leave, all but
the 1/15 ones.

Namely:
I really think we want to have reference to where the import came
from. That plus keeping any other changes (even if code motion) as
separate patches.

With that the series is:
Reviewed-by: Emil Velikov <emil.velikov at collabora.com>

-Emil