d908984d68
In this scenario: 1. Only an "empty" content update (which results in no visible output change) from client A arrives before the frame deadline, so a frame event is sent for that at the deadline. 2. Another "empty" content update from client A results in a frame event being scheduled for the next frame deadline. 3. A non-"empty" content update from client B arrives before start of vblank, and the resulting output frame manages to hit the next display refresh cycle. The result was that the frame events from steps 1+2 were sent during the same display refresh cycle, so the frame rate reported by client A was higher than the display refresh rate. This change fixes that, at the cost of frame events being sent out later in the display refresh cycle if there's no new frame for the next cycle. Closes: https://gitlab.gnome.org/GNOME/mutter/-/issues/3559 Fixes: 8f27ebf87eee ("clutter/frame-clock: Start next update ASAP after idle period") Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/3878>
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 first look at the GNOME Handbook and the documentation and API references below first.
Documentation
- Coding style and conventions
- Git conventions
- Code overview
- Building and Running
- Debugging
- Monitor configuration
API Reference
- Meta: https://mutter.gnome.org/meta/
- Clutter: https://mutter.gnome.org/clutter/
- Cogl: https://mutter.gnome.org/cogl/
- Mtk: https://mutter.gnome.org/mtk/
Meetings
There are recurring meetings to discuss development of GNOME Shell, mutter and related components.
License
Mutter is distributed under the terms of the GNU General Public License, version 2 or later. See the COPYING file for detalis.