Fwd: allowShmPixmaps

[Mark Wielaard]

Hi Clemens,

On Sat, 2008-11-29 at 20:11 +0100, Clemens Eisserer wrote:
> Its always JNI_TRUE when it is called from within the X11 pipeline,
> but when called from the XRender pipeline (
> Java_sun_java2d_xr_XRSurfaceData_initIDs ) SHMPixmaps are disabled.

O, right, sorry I missed that.

> The reason is that SHMPixmaps are ususally a bad if you would like
> them accalerated by the driver, because they cause pixmaps to be bound
> to system-memory usually - however the X11 pipeline relies on it for
> good performance when mixing server/client rendering.
> However SHMPixmaps are not supported by EXA based drivers and the
> latest NVidia beta release also disables them by default, so usually
> we won't get them anyway ;)

Aha. I am still learning lots of how the (accelerated) X11 pipelines
work.

> By the way, I intend to rewrite the whole MaskBuffer stuff soon, as
> well as large amounts of the C code.
> I am not really used to C, so sorry if the code is quite ugly in some cases.

You seem to do fine. It is really exciting work. Not only do java2d
programs work faster, they actually are usable over a remote X
connection now.

I was just going over the code to see if I understood how the separation
between X11 and XR was setup, to convince myself that the old pipeline
isn't changed in any way when the xrender pipeline isn't activated.

Cheers,

Mark