Improving rotated ATI performance

[Jerome Glisse]

On Fri, 14 Dec 2007 16:57:46 +0100
Roland Scheidegger <sroland at tungstengraphics.com> wrote:

> Alex Deucher wrote:
> > On Dec 14, 2007 9:25 AM, Jerome Glisse <glisse at freedesktop.org> wrote:
> >> On Thu, 13 Dec 2007 13:24:22 -0500
> >> "Alex Deucher" <alexdeucher at gmail.com> wrote:
> >>
> >>> On Dec 13, 2007 1:19 PM, Adr3nal D0S <adr3nald0s at gmail.com> wrote:
> >>>> On Dec 13, 2007 11:37 AM, Alex Deucher <alexdeucher at gmail.com> wrote:
> >>>>
> >>>>> rotation can use EXA composite to accelerate transforms, so you'll
> >>>>> have to use EXA.  For r1xx-r2xx the composite code is written, but
> >>>>> there are some bug when doing transforms, so it doesn't work properly
> >>>>> for rotation.  for r3xx and newer, the code needs to be written.
> >>>>> there should be enough info available for r3xx-r4xx in the 3D driver
> >>>>> to add composite support, but no one has done the work yet.
> >>>> I've done a fair amount of OpenGL over the years, but haven't dealt
> >>>> with 3D much at the hardware level.  Am I correct that 3D acceleration
> >>>> only works up to a maximum virtual size of 2048x2048? If so, does this
> >>>> mean it would be impossible to have accelerated compositing under EXA
> >>>> for larger virtuals?
> >>> It depends on the hardware.  r1xx and r2xx had 2048 3d coordinate
> >>> limits and tiling surface limits.  r3xx/r4xx are 4096.  textures are
> >>> limited to 2048 on r1xx-r4xx.
> >> Alex would be good if you can double check but r300 hw i got can't
> >> properly render 3d above 2650x2650 (offset things you can see in the
> >> drm). As side note fglrx doesn't render properly above this limit.
> >> So i think we should change advertized viewport size to 2650, i
> >> will do that soon if no one object with valid arguments.
> >>
> > 
> > you are right the r3xx r4xx car limited to 2560.  I forgot about that.
> >  Go ahead and fix that up.
> Is this really true for all r3xx and r4xx cards? I thought at least some
> r4xx cards could do more.
> 
> Roland

I don't have r4xx hw anymore :( but as this restriction looks like a hw
bug this might effectively mean that r4xx can do more and reach 4096.
I know that r5xx can do 4096 (maybe even more but i can remember up
to what).

Cheers,
Jerome Glisse