A tool for wlroots-based compositors that automatically adjusts screen brightness based on the screen contents and amount of ambient light around you.
The app will automatically brighten the screen when you are looking at a dark window (such as a fullscreen terminal) and darken the screen when you are looking at a bright window (such as web browser). The algorithm takes into consideration the amount of ambient light around you, so the same window can be brighter during the day than during the night.
With permission of Lumen's author (the project that inspired me to create this app), I'm reusing a demo GIF:
Simply launch wluma
and continue adjusting your screen brightness as you usually do - the app will learn your preferences.
wluma
will not do anything on the first launch! You have to adjust the brightness by hand a few times, in different environment and/or with different screen contents, that way wluma
will learn your preferences and only then it will begin to automatically change your screen brightness for you.
The app has minimal impact on system resources and battery life even though it is able to monitor screen contents several times a second. This is achieved by using export-dmabuf Wayland protocol to get access to the screen contents and doing computations entirely on GPU using Vulkan API.
Use one of the available packages and methods below:
glibc
, which might not work on your machine if your version is too old)sudo make install
If you want to build the app yourself, make sure you use latest stable Rust, otherwise you might get compilation errors! Using rustup
is perhaps the easiest. Ubuntu needs the following dependencies: sudo apt-get -y install v4l-utils libv4l-dev libudev-dev libvulkan-dev libdbus-1-dev
.
Then simply run make build
.
In order to access backlight devices, wluma
must either:
90-wluma-backlight.rules
udev rule, add your user to the video
group and reboot (fastest)elogind
or systemd-logind
(they provide a safe interface for unprivileged users to control device's brightness through dbus
, no configuration necessary)root
(not recommended)The config.toml
in repository represents default config values. To change them, copy the file into $XDG_CONFIG_HOME/wluma/config.toml
and adjust as desired.
Choose whether to use a real IIO-based ambient light sensor ([als.iio]
), a webcam-based simulation ([als.webcam]
), a time-based simulation ([als.time]
) or disable it altogether ([als.none]
).
Each of them contains a thresholds
field, which comes with good default values. It is there to convert generally exponential lux values into a linear scale to improve the prediction algorithm in wluma
. Keys are the raw values from ambient light sensor (maximal value depends on the implementation), values are arbitrary "profiles". wluma
will predict the best screen brightness according to the data learned within the same ALS profile.
Multiple outputs are supported, using backlight
(common for internal laptop screens) and ddcutil
(for external screens).
Each output is identified by compositor using model, manufacturer and serial number (e.g.eDP-1 'Sharp Corporation 0x14A8 0x00000000' (eDP-1)
.
The name
field in the output config will be matched as a substring, so you are free to put simply eDP-1
, or a serial number (if you have two identical external screens). It is your responsibility to make sure that the values you use match uniquely to one output only.
The capturer
field will determine how screen contents will be captured. Currently supported values are wlroots
(works only on wlroots-based Wayland compositors) and none
(ignores screen contents and predicts brightness only based on ALS).
Tip: run wluma
with RUST_LOG=debug
to see how your outputs are being identified, so that you can choose an appropriate name
configuration value.
To run the app, simply launch wluma
or use the provided systemd user service.
To enable logging, set environment variable RUST_LOG
to one of these values: error
, warn
, info
, debug
, trace
.
For more complex selectors, see env_logger's documentation.
Help is wanted and much appreciated! If you want to implement some of these, feel free to open an issue and I'll provide more details and try to help you along the way.
wluma
. Until then, a workaround is to export WLR_DRM_NO_MODIFIERS=1
before launching your wlroots-based compositor.wluma
is running is not supported yet, and should crash the app. Workaround: restart wluma
after changing resolution.wluma
is running. Workaround: restart wluma
.