c2c4f74923
Compare, tile by tile, whether actual damage actually changed any pixels. While this requires mmap():ing DMA buffers and comparing their content, we should only ever use shadow buffers when we're using the software renderer, meaning mmap() is cheap as it doesn't involve any downloading. This works by making the shadow framebuffer double buffered, while keeping track of damage history. When we're about to swap the onscreen buffer, we compare what part of the posted damage actually changed, records that into a damage history, then given the onscreen buffer age, collect all actual damage for that age. The intersection of these tiles, and the actual damage, is then used when blitting the shadow buffer to the onscreen framebuffer. Closes: https://gitlab.gnome.org/GNOME/mutter/-/issues/1157 https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1237
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 af 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.
The coding style used is primarily the GNU flavor of the GNOME coding
style
with some minor additions such as preferring stdint.h types over GLib
fundamental types, and a soft 80 character line limit. However, in general,
look at the file you're editing for inspiration.
Commit messages should follow the GNOME commit message guidelines. We require an URL to either an issue or a merge request in each commit.
License
Mutter is distributed under the terms of the GNU General Public License, version 2 or later. See the COPYING file for detalis.