r300 opengl lagre screen limitation

[Stanislovas Mickus]

> 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.
It looks you're right because I could get up to ~2650 pixels with some
minor mesa tweak. So anyone knows why we need this magic with
R300_CLIPRECT_OFFSET in r300_cmdbuf.c in drm? I could not find similar
thing in other drm drivers.

> 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.
Yep, it should be quite a rework and questionable reword, because I
think modern graphics hardware is starting to support these high
resolutions in hardware.

> 
> Cheers,
> Jerome Glisse
> 
> PS: avoid to cross post
>