[Mesa-dev] Another Take on the S3TC issue

[Roland Mainz]

On Tue, Aug 13, 2013 at 10:20 PM, Ian Romanick <idr at freedesktop.org> wrote:
> On 08/13/2013 11:53 AM, Uwe Schmidt wrote:
[snip]
>> SO MY PROPOSAL:
>>
>> If 'format' is one of the S3TC types, and format!=internalFormat is true,
>> then set internalFormat:=format.
>
> 'format' cannot be a compressed type.  Compressed data can only be supplied
> using glCompressedTexImage2D, and that function only has an internalFormat
> parameter.
>
>
>> Else, if 'internalFormat' is one of the S3TC types, but the 'format'
>> isn't,
>> set internalFormat:=format (or any other format, Mesa3D can encode).
>
>
> The only format that Mesa can encode is FXT1.  Only Intel hardware supports
> FXT1, and the quality (of Mesa's compressor) is not very good.  Picking that
> format would result in bug reports of "game XYZ looks horrible on Intel
> graphix you suck."  So that leaves us with the only option of leaving the
> data uncompressed.
>
> Until S3 grants it's IP to OIN or the patents expire, this is going to be
> the situation.  We've been through this mental exercise of the last 5 years
> more times than I can count, and we always come back to the same place.

Please don't hit me with a stick if this has been asked
|powl(INT64_MAX, INT64_MAX)| times... but... erm... adding the code
(sample implementation, "... do not use without a license from S3 and
the ritual scarification of at least one software engineer...") but
having it off in the default build won't work... right ?

----

Bye,
Roland

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