Wine and XShm support

[Roderick Colenbrander]

On Mon, Aug 10, 2009 at 11:17 PM, Yuriy Kaminskiy<yumkam at mail.ru> wrote:
> On 10.08.2009 12:24, Henri Verbeet wrote:
>>> at least add a registry key for it and disable it perhaps on 'modern
>>> drivers'). What do you guys think?
>> Could you do some benchmarking? You can disable XShm support by
>> passing "--without-xshm" to configure.
>
> Note that problem is only with *Shm*Pixmap*. *Shm*Image* is fine. So
> --without-xshm will disable too much.
>
> AFAIR, with really modern nvidia drivers (>=180.x), Xserver should report
> 'ShmPixmap unsupported' in XShmQueryVersion (see driver's README about 'Option
> "AllowSHMPixmaps"'; check `xdpyinfo -ext MIT-SHM` to be sure); so new ShmPixmap
> code should be already no-op on nvidia and not cause pessimization ;-) [not sure
> about Intel and others; so, maybe, adding wine option still make sense].
>
>
>
>

Thanks Yuriy I wasn't aware of the pixmap query in XShmQueryVersion,
so apparently we already disable XShm on at least Nvidia drivers.
Hopefully other drivers do the same, I should ask some Xorg
developers.

The test I added is not really correct and doesn't stress the
dibsection code. I would have to modify the test to render to the
dibsection to do a better job.

Roderick