Comment 82 for bug 179042

I have 2 laptops:

One Lenovo Thinkpad R61 (with Nvidia graphics card) and a Fujitsu Siemens
Esprimo Mobile (with integrated intel graphics card).

I did a fresh Jaunty install on both machines and installed Google Earth.
The Nvidia PC runs smooth, the Intel doesn't.

Micro Müeller explains what happens in detail in the original BUG report for
this problem:

   - https://bugs.launchpad.net/ubuntu/+source/compiz/+bug/162541

Summary: Wait for DRI2.

Full description from Müeller:

Every OpenGL-based application running under compiz (and being driven by
OpenSource Xorg-drivers or ATI's flgrx) will yield rendering glitches as
described, because the drivers in question are all still based on DRI and
not DRI2. What DRI lacks and DRI2 introduces - among other things - is
hw-accelerated indirect rendering. This affects composited window-managers
(like compiz) mostly. Currently with DRI the DRM does not care if the
desktop is composited or not and just hands any OpenGL-app, that asks for a
rendering-context to draw to, a pointer to the front-buffer. Thus the
OpenGL-app happy starts drawing to the front-buffer, ignoring the fact that
there might be a compositing manager running and it should rather render to
an off-screen area and let the compositing-manager do the work of blitting
the OpenGL-apps window-contents to the front-buffer. DRI2 is more
intelligent in that regard in fixes this.

All that is overly simplified of course, but should give an idea about what
is going on "under the hood".

On nvidia (using the proprietary driver) one does not run into this issue
because nvidia does not use any form of DRI but their own infrastructure,
which happens to have hw-accelerated indirect rendering for some time now.
If one would be so bold to use the OpenSource nouveau-driver, they'd see the
same rendering glitches. But nouveau will of course also switch to DRI2.

Over time all OpenSource Xorg-video-driver will switch to DRI2 of course. It
will take time. The first driver that is pretty far in development to adapt
to DRI2, is the intel-video driver (for i915, i945 and i965 that should work
already). Second in line will probalby be the OpenSource radeon-driver (the
one without HD in the name).

Regards,
Cenora

On Thu, Apr 23, 2009 at 3:31 AM, rja <email address hidden> wrote:

> Just upgraded to 9.04 RC, and I have fglrx version 2:8.600-0ubuntu2.
> FYI, I'm running 64-bit Ubuntu.
>
> Specifically, while running Compiz - Played an AVI file in windowed mode
> (Totem movie player):
> - First the video didn't show up, but then I switched to Metacity, and then
> back to Compiz, and the video is working fine now.
> - Rotated the desktop cube, and the video moved perfectly, as expected.
> - Switched to fullscreen mode, and movie continued to play well
> - Rotated the desktop cube, and the rotation was still good - the video
> playing face of the cube showed the movie correctly.
>
> Chris Roddy, are you having trouble with 3D or video? I think the issues
> with 3D aren't yet fixed:
>
> 1. Running glxgears, if I rotate the desktop cube, the window border moves
> with the desktop, but the gears themselves stay in the same spot on the
> screen.
> 2. Running glchess from gnome-games package, when switching to 3D-View,
> there is a lot of blinking and switching back to 2D mode.
>
> But I think that's probably a different bug. Can someone point me the
> appropriate bug report?
>
> --
> Videos tear and "blink" when enabling compiz [AMD Feature #7647]
> [EPR#257833]
> https://bugs.launchpad.net/bugs/179042
> You received this bug notification because you are a direct subscriber
> of the bug.
>