Cairo drawing coordinates are broken w/nouveau (affects xfwm4)
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
xorg (Ubuntu) |
Expired
|
Undecided
|
Unassigned |
Bug Description
I'm using xfwm4 with Xubuntu 16.04. With compositing enabled, and when I cycle through windows with Alt-Tab, xfwm4 draws an opaque rectangle bordering a candidate window, and it fills that rectangle with a semi-transparent blue color. When I use the nouveau driver, the filled rectangle is clipped. The problem does not reproduce with the proprietary nvidia driver.
It seems as though a drawing command should be issued using a window-relative coordinate, but sometimes is instead issued using a screen-relative coordinate.
I extracted relevant bits of xfwm4 into a small test program that reproduces the problem. The test program creates a transparent XWindow at (100,100) with size (210,210). It draws six rectangles centered inside the window of varying parameters. Two of them are drawn at the wrong place.
xfwm4 should be off-the-hook, I think, unless it's doing something wrong (e.g. unspecified/
$ lsb_release -rd
Description: Ubuntu 16.04.1 LTS
Release: 16.04
$ apt-cache policy xserver-
xserver-
Installed: 1:1.0.12-1build2
Candidate: 1:1.0.12-1build2
Version table:
*** 1:1.0.12-1build2 500
500 http://
100 /var/lib/
$ apt-cache policy xfwm4
xfwm4:
Installed: 4.12.3-1ubuntu2
Candidate: 4.12.3-1ubuntu2
Version table:
*** 4.12.3-1ubuntu2 500
500 http://
100 /var/lib/
I created a video demonstrating the problem in xfwm4: https:/
FWIW, I'm using an NVIDIA GeForce GTX 750 Ti card.
ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: xorg 1:7.7+13ubuntu3
ProcVersionSign
Uname: Linux 4.4.0-31-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.1
Architecture: amd64
CurrentDesktop: XFCE
Date: Mon Jul 25 00:50:21 2016
InstallationDate: Installed on 2016-07-19 (6 days ago)
InstallationMedia: Xubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1)
SourcePackage: xorg
Symptom: display
UpgradeStatus: No upgrade log present (probably fresh install)
Here's what the test program's output *should* look like, using the NVIDIA driver.
$ apt-cache policy nvidia-361 us.archive. ubuntu. com/ubuntu xenial/restricted amd64 Packages dpkg/status
nvidia-361:
Installed: 361.42-0ubuntu2
Candidate: 361.42-0ubuntu2
Version table:
*** 361.42-0ubuntu2 500
500 http://
100 /var/lib/