
The initial target color state is the color state of the stage view being painted to. If we're painting to an arbitrary framebuffer, it's currently hard coded to sRGB/electrical. The content color state is not set on construction, but when starting to paint, it's set to the color state of the stage itself. Whenever an actor is painted, it'll set the color state to the color state of itself. The intention is that offscreen rendering pushes a target color state that causes painting to it to not necessarily be in the stage view color state. Pass color state with offscreen framebuffer, as this avoids hard coding sRGB in the lower level bits of paint contexts. It's still practically hard coded, only that it's derived from somewhere else (e.g. the stage or window actor). Nothing is actually using this yet, but will eventually. Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/3433>
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/
- Cally: https://mutter.gnome.org/cally/
- Cogl: https://mutter.gnome.org/cogl/
- CoglPango: https://mutter.gnome.org/cogl-pango/
- 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.