5daddf0bc7
With the move away from GTK3, and the indirect dependency on GTK4 grown in the GNOME Shell side, we've indirectly gotten a small sneaky behavioral change: The GTK4 library will, right on dlopen, get DESKTOP_AUTOSTART_ID for itself and delete it from the environment. This happens before our own X11 session management code is initialized, which confuses the hell out of it, into thinking initialization is actually shutdown, gnome-session does not follow along with this request, which leaves GNOME Shell into a confused startup state where it never calls SmcSaveYourselfDone() and grinds startup to a halt until gnome-session decides to move things forward. In order to fix this, get the DESKTOP_AUTOSTART_ID before we lend control to GNOME Shell bits and GTK4 is possibly initialized, and feed it directly to our X11 session manager bits. Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2906>
Mutter
Mutter is a Wayland display server and X11 window manager and compositor library.
When used as a Wayland display server, it runs on top of KMS and libinput. It implements the compositor side of the Wayland core protocol as well as various protocol extensions. It also has functionality related to running X11 applications using Xwayland.
When used on top of Xorg it acts as a X11 window manager and compositing manager.
It contains functionality related to, among other things, window management, window compositing, focus tracking, workspace management, keybindings and monitor configuration.
Internally it uses a fork of Cogl, a hardware acceleration abstraction library used to simplify usage of OpenGL pipelines, as well as a fork of Clutter, a scene graph and user interface toolkit.
Mutter is used by, for example, GNOME Shell, the GNOME core user interface, and by Gala, elementary OS's window manager. It can also be run standalone, using the command "mutter", but just running plain mutter is only intended for debugging purposes.
Contributing
To contribute, open merge requests at https://gitlab.gnome.org/GNOME/mutter.
It can be useful to look at the documentation available at the Wiki.
The API documentation is available at:
- Meta: https://gnome.pages.gitlab.gnome.org/mutter/meta/
- Clutter: https://gnome.pages.gitlab.gnome.org/mutter/clutter/
- Cally: https://gnome.pages.gitlab.gnome.org/mutter/cally/
- Cogl: https://gnome.pages.gitlab.gnome.org/mutter/cogl/
- CoglPango: https://gnome.pages.gitlab.gnome.org/mutter/cogl-pango/
Coding style and conventions
See HACKING.md.
Git messages
Commit messages should follow the GNOME commit message
guidelines. We require an URL
to either an issue or a merge request in each commit. Try to always prefix
commit subjects with a relevant topic, such as compositor: or
clutter/actor:, and it's always better to write too much in the commit
message body than too little.
If a commit fixes an issue and that issue should be closed, add URL to it in
the bottom of the commit message and prefix with Closes:.
Do not add any Part-of: line, as that will be handled automatically when
merging.
The Fixes tag
If a commit fixes a regression caused by a particular commit, it can be marked
with the Fixes: tag. To produce such a tag, use
git show -s --pretty='format:Fixes: %h (\"%s\")' <COMMIT>
or create an alias
git config --global alias.fixes "show -s --pretty='format:Fixes: %h (\"%s\")'"
and then use
git fixes <COMMIT>
Example
compositor: Also consider dark matter when calculating paint volume
Ignoring dark matter when calculating the paint volume missed the case where
compositing happens in complete vacuum.
Fixes: 123abc123ab ("compositor: Calculate paint volume ourselves")
Closes: https://gitlab.gnome.org/GNOME/mutter/-/issues/1234
Default branch
The default development branch is main. If you still have a local
checkout under the old name, use:
git checkout master
git branch -m master main
git fetch
git branch --unset-upstream
git branch -u origin/main
git symbolic-ref refs/remotes/origin/HEAD refs/remotes/origin/main
License
Mutter is distributed under the terms of the GNU General Public License, version 2 or later. See the COPYING file for detalis.