Present extension and TearFree on Intel

[Keith Winstein]

Hello all,

First off, thank you for making the Present extension -- it looks like a
very welcome addition to X11.

I am trying to use PresentPixmap to display a pixmap in vblank-synchronized
manner with Xorg 1.15.1, xserver-xorg-video-intel 2:2.99.910-0ubuntu1.2,
and Intel HD Graphics 3000, but in practice we see lots of tearing unless
we enable the "TearFree" option. This does not seem to be the default with
a blank xorg.conf.

By contrast, OpenGL code that uses the swap interval extensions works great
out of the box.

Here is a demo that demonstrates the problem:
https://github.com/keithw/present-demo

Is there a recommended workaround that an application can use? Ideally we
would be able to distribute programs that use Present without asking users
to change their xorg.conf.

Thanks very much,
Keith Winstein
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.x.org/archives/xorg-devel/attachments/20141110/87cf1e93/attachment.html>