A brightness control dockapp in the style of wmix. Allows control of backlight level for some laptop monitors and gamma manipulation for most outputs.
Upon starting, wmbright detects all active outputs and tries to determine the best way to control their brightness. Backlight control is used if available, with gamma manipulation as a fallback. There are multiple ways to control brightness with wmbright:
- Click and drag on the knob
- Use the mouse wheel anywhere inside the dockapp
- Use the standard brightness keys if available on your keyboard
- Send the signals SIGUSR1 and SIGUSR2
Initially, wmbright is set to the "ALL" output which means that any brightness change is applied to all available outputs simultaneously. Use the arrow buttons on the bottom left to select individual outputs instead.
Above the arrow buttons are indicators for the different brightness control methods. Typically "BL", i.e., backlight, is superior as it will actually control the backlight of your monitor rather than just changing the colours of the pixels, but if you prefer gamma manipulation, click on the gamma indicator to switch to the gamma method. When wmbright is set to the "ALL" output, clicking the the indicators will (try to) switch the method of all outputs at once.
wmbright will read configuration values from a .wmbrightrc file in your home directory. The values understood are the following (these are also the defaults, in case no configuration file is found):
# 1 = yes, 0 = no
mousewheel=1 # use mousewheel?
scrolltext=1 # scroll output names when they don't fit
osd=1 # display OSD?
osdcolor=green # color of the OSD (from rgb.txt)
wheelbtn1=4 # which mouse button is "wheel up"
wheelbtn2=5 # which mouse button is "wheel down"
wheelstep=3 # the step for mouse wheel adjustment
Additionally, an exclude parameter is understood, allowing outputs to be excluded from wmbright control:
exclude=HDMI-0
exclude=DVI-I-1
A sample configuration file is provided in sample.wmbrightrc.
Run wmbright -h to list the command line parameters.
wmbright uses libxrandr to manipulate backlight as well as gamma. Sometimes xrandr cannot access the backlight property out of the box. If your system contains the directory /sys/class/backlight/intel_backlight but backlight manipulation does not work, it is likely that this can be remedied by adding the file /etc/X11/xorg.conf.d/20-video.conf with the following contents (or modifying your current xorg config to the same effect):
Section "Device"
Identifier "Intel Graphics"
Driver "intel"
Option "Backlight" "intel_backlight"
EndSection
(courtesy of the Arch Wiki, https://wiki.archlinux.org/title/backlight)
Night light applications such as redshift typically use the same gamma controls as wmbright. If your brightness seems to revert shortly after adjusting it with wmbright, it's likely that you have some sort of night light software running. There is not much that can be done about this outside of disabling the night light app.