r300 opengl lagre screen limitation

[Jerome Glisse]

Stanislovas Mickus wrote:
> Hello,
> I'm not sure if this the right place to write this, but I want to
> resolve r300 driver limitation to render opengl just till 2560 pixel
> width. There is a bug filled on this subject(#8357).
> So I would like to solve this problem. Although I'm not experienced in
> 3D drivers
> and xorg server programming, I'm willing to invest time to solve it.
> I need assistance and information on what needs to be done to accomplish this.
> I read various thoughts about solutions. 
> One of them is mentioned in a link above. That is, playing with cliprects and
> radeon registers (R300_SE_VPORT_XOFFSET,R300_SE_VPORT_YOFFSET,
> R300_RB3D_COLOROFFSET0, R300_RB3D_DEPTHOFFSET).
> Other idea is splitting 3d context into more contexts and offsetting them with
> RE_TOP_LEFT register if its possible.
> It would be nice to here opinion of people who have some knowledge on this
> topic.
> 
> Thanks

I already added comment in bug 8357 and truely first step is to
get rid of this 1440 magic offset in cliprect which should enable
to go full size for 3d ie 4096 which likely enough for most users.

In case you want to go above 4096 up to 8192 (which is hw limit
you can't work around) then you need to add heavy infrastructure
which should be generic for all drivers. But such things need
massive work in mesa,ddx,... and no work at all in r300 driver.
Of course you can also make modification only for r300 but i
believe this would be wrong solution and likely not accepted
upstream.

Cheers,
Jerome Glisse