Window with no background contains random data with composite

[Olivier Fourdan]

Creating a window with no pixmap and no bg color when using a compositor in Ubuntui Edgy returns a pixmap with random data.

Without a compositor, creating a window w/out a back pixmap nor a bg color gives a windows inheriting underlying content (ie whatever was under the window at the time of creation).

When running a compositor with Xorg 7.0 in Dapper, it works the same. But when running a compositor with Xorg 7.1 in Edgy, the window shows with random data, not unlike an uninitialized pixmap...

This is a problem because many apps, like gtk+, create its top level windows w/out bg pixmap or pixel and it shows when running a compositor

I reported this to the Xorg guys, along with a test case and relevant screenshots, but I've been told that it works fine with their version, and that's a bug with a patch applied by the distribution.

Please see https://bugs.freedesktop.org/show_bug.cgi?id=8558 for a complete report with test case and screenshots.

[Olivier Fourdan (fourdan)]

Created an attachment (id=7288)
Test case

[Olivier Fourdan (fourdan)]

Created an attachment (id=7289)
A window with no background without any compositor running

This shows the "regular" expected behavior w/out any compositor running

[Olivier Fourdan (fourdan)]

Created an attachment (id=7290)
A window with no background with a compositor in Xorg 7.0

The window has no content with a compositor in Xorg 7.0, this is the expected
behavior.

[Olivier Fourdan (fourdan)]

Created an attachment (id=7291)
A window with no background with a compositor running in Xorg 7.1

Now, in Xorg 7.1, when a compositor is running, the window shows random data.
The problem shows equally when using XCompositeNameWindowPixmap () or when
accessing the drawable id directly. It seems that the buffer pixmap is not
properly initialized in Xorg 7.1.

[Michel-tungstengraphics (michel-tungstengraphics)]

The test case works fine here with current git (and the xfwm4 compositor :). Did
you build the X server yourself? Some distros use a patch with this effect for
performance reasons.

[Olivier Fourdan (fourdan)]

I'm using Ubuntu Edgy on an AMD64.

[Olivier Fourdan (fourdan)]

Yeap, ok, I've filled a bug in Launchpad for Ubuntu then.

[Olivier Fourdan (fourdan)]

Creating a window with no pixmap and no bg color when using a compositor in Ubuntui Edgy returns a pixmap with random data.

Without a compositor, creating a window w/out a back pixmap nor a bg color gives a windows inheriting underlying content (ie whatever was under the window at the time of creation).

When running a compositor with Xorg 7.0 in Dapper, it works the same. But when running a compositor with Xorg 7.1 in Edgy, the window shows with random data, not unlike an uninitialized pixmap...

This is a problem because many apps, like gtk+, create its top level windows w/out bg pixmap or pixel and it shows when running a compositor

I reported this to the Xorg guys, along with a test case and relevant screenshots, but I've been told that it works fine with their version, and that's a bug with a patch applied by the distribution.

Please see https://bugs.freedesktop.org/show_bug.cgi?id=8558 for a complete report with test case and screenshots.

[Bryce Harrington (bryce)]

Thank you for reporting this bug in Edgy. Could you please test it against Gutsy to see if the problem exists in Ubuntu's current development tree?

[Launchpad Janitor (janitor)]

[Expired for xorg (Ubuntu) because there has been no activity for 60 days.]