[Mesa-dev] [PATCH] st/mesa: Override blend factors involving alpha if it doesn't exist.

[Marek Olšák]

On Mon, Aug 27, 2018 at 5:55 PM, Kenneth Graunke <kenneth at whitecape.org> wrote:
> On Monday, August 27, 2018 11:05:19 AM PDT Marek Olšák wrote:
>> Yeah, this will be more complicated because it's per RT.
>>
>> I suggest adding a PIPE_CAP for the hw capability to force DST_ALPHA
>> to 0, and applying this workaround only if the PIPE_CAP is 0.
>>
>> Marek
>
> I was thinking of applying this hack based on PIPE_CAP_INDEP_BLEND_FUNC.
>
> Ilia seemed to think that it was unsupportable on older Nouveau (without
> independent alpha blending), but harmless either way on modern Nouveau.
> (Supposedly Freedreno does this workaround in the driver...)
>
> Would you prefer not to have this triggered?

Yes. I think it would be unnecessary overhead for us.

Marek