[Mesa-dev] [PATCH] radeonsi: Fix blending using destination alpha factor but non-alpha destination

[Michel Dänzer]

On Die, 2013-02-19 at 14:04 +0100, Marek Olšák wrote: 
> On Tue, Feb 19, 2013 at 11:02 AM, Michel Dänzer <michel at daenzer.net> wrote:
> >
> > Really, what I don't understand is why r600g doesn't seem affected by
> > this... at least on my RS880 it's passing the piglit tests this change
> > fixes with radeonsi. So maybe I'm just missing some magic bit for
> > radeonsi.
> 
> RGB formats do fail fbo-blending-formats with r600g/redwood here.

Okay.


> However the alpha channel can sometimes contain 1 in memory even if
> the format is RGBX. Off the top of my head, glClear, glTex[Sub]Image,
> glCopyTex[Sub]Image always set alpha to 1.

Well, but they shouldn't for these formats. :) The memory corresponding
to X* channels should remain unchanged. I'm working on a separate patch
for that for radeonsi.


-- 
Earthling Michel Dänzer           |                   http://www.amd.com
Libre software enthusiast         |          Debian, X and DRI developer