[compiz] AIGLX Support with nVidia 9625 Drivers

[wakko at generation.no]

On Tue, September 26, 2006 4:56 pm, David Reveman wrote:
> On Mon, 2006-09-25 at 18:18 -0700, Soup Laddy wrote:
>
>> Something I've been worried about: I have an nVidia GeForce FX 5500
>> card, and I'd been noticing some extreme tearing in XGL when
>> rotating/manipulating the cube and moving around windows... a somewhat
>> of a fix to that was to start XGL with __GL_SYNC_TO_VBLANK=1 ... but
>> that then reduced performance. Is the tearing problem at all resolved
>> with Compiz + AIGLX?
>
> Both xgl and aiglx implement indirect GL rendering. Hence all blits and
> buffer swaps are done on the server side. If you force the driver to sync
> to vblank (e.g. __GL_SYNC_TO_VBLANK), you usually force the server to
> block and wait for the vblank. You get horrible performance this way as
> this leaves the server very little time to process other X requests. I
> have a patch that makes it possible for xgl to do buffer swaps in a
> separate thread, hence making sure the main thread that is processing X
> requests isn't blocked. However, last time I checked, there were no
> drivers that could handle GL drawing from multiple threads to one drawable
> properly.
>
> nvidia's new driver with GLX_EXT_tfp, support direct rendering. When using
> this driver with direct rendering all blits and buffer swaps are done on
> the client side by compiz itself. Blocking and waiting for vblank in
> compiz will not stop the server from continuing to process X requests so
> there's no performance impact on the server. The compiz code for doing
> this is already in head and if you use the new nvidia driver with direct
> rendering it should be turned on by default. There's a sync_to_vblank
> option which allow you turn it off. Don't use __GL_SYNC_TO_VBLANK, compiz
> is using GLX_SGI_video_sync to sync even partial screen updates to vblank.
>
>
> -David
>
>
> _______________________________________________
> compiz mailing list compiz at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/compiz
>
>

Does nvidia even use aiglx? doesn't nvidia have it's own accelerated
indirect rendering architecture?

-anders