oled-linux.sh will watch the backlight changes in /sys/class/backlight/intel_backlight and apply changes over there to OLED screens

• Brightness Change on OLED screens on Linux (main point of the repository)
• Smooth Brightness Control (changes in brightness will be applied gradually instead of just jumping to the new brightness)
• Night Light Support (with or without geolocation and with smooth cycle changes)
• Multiple Displays Support
• Works directly on X, is not tightly coupled to any desktop environment, so it should work well in almost any circumstance

• inotifywait - used for watching for file changes with as little CPU usage as possible
• sunwait - (optional) used for monitoring day/night cycle for night light feature
• geoclue2 - (optional) used for getting current location for day/night cycle for night light feature. Optional because locaiton can be set manually

Clone the repository and add get-current-location.sh, watch-location.sh, run-set-day-night.sh, oled-linux.sh to your .xinitrc This is an example of an .xinitrc that loads oled-linux for a user that is using i3. Note that the oled-linux scripts must be invoked before your window manager is started.

<path-to>/oled-linux/get-current-location.sh &  # optional, for night-light-geolocation
<paht-to>/oled-linux/watch-location.sh &        # optional, for night-light-geolocation
<path-to>/oled-linux/run-set-day-night.sh &     # optional, for night-light
<path-to>/oled-linux/oled-linux.sh &
exec i3

If night light is enabled (by default it is), all brightness changes are applied using redshift, which allows for nightlight support. If night light is disabled in the config, brightness changes will be applied with xrandr. oled-linux.sh will also watch for the file file-pipes/day-night.txt, and if the contents of the file are NIGHT, a night filter will be applied

Default vaules for night filter DAY = 6500 (default, unchanged display) NIGHT = 3500 (default night-filter value)

We can change the night filter value to whatever you want by modifying oled-linux.sh (see configuration section). W can also adjuse the daylight value so we can add a filter during the day too.

Night Light can work without geolocation, in which case you can skip loading get-current-location.sh and watch-location.sh, but if this option is chosen, one must provide location manually in file-pipes/location.txt in the following format: LATITUDE_DEGREES[N/S] LONGITUDE_DEGREES[E/W].

> cat location.txt
26.123000N 12.578000E

Configuration is provided at the top of oled-linux.sh.

# where is the backlight directory?
backlight_dir="/sys/class/backlight/intel_backlight/"

# which screen is the oled panel?
# if not set, it will default to `xrandr | grep -m 1 ' connected ' | awk '{print $1}'`
# leaving it empty will "just work" in most cases
#
# do xrandr command for a list of screen names
# e-DP1 is an example of a good screen name
oled_screen=''

# how much to change the brightness on one frame
# or how smooth should the brightness changes be
# the lower the value the longer it takes to transition to a new brightness
# has to be an integer value, no fractional values are allowed
brightness_step_size=12

# if true, the program will look for changes in 'day_night.txt' and update the redshift temperature accordingly
# check 'set_day_night.sh' to see how 'day_night.txt' is updated
use_redshift=true

# nightshift temperature during the day
daylight_temperature=6500

# nightshift temperature during the night
night_temperature=3500

# how much to change the temperature of the night light on one frarme
# the lower the value, the longer it takes to transition to a new redshift temperature
# has to be an integer value, no fractional values are allowed
redshift_step_size=50

oled-linux.sh uses inotifywait to watch for changes in file-pipes/day-night.txt and /sys/class/backlight/intel_backlight, so it will only work when there are some brightness changes to apply.

get-current-location.sh checks for location information using geoclue2 every 10 minutes and writes that info to file-pipes/current-location.sh

watch-location.sh watches for changes in file-pipes/current-location.sh and if the location changed, writes the new location to file-pipes/location.txt

set-day-night.sh writes DAY or NIGHT to file-pipes/current-location.sh whenever it becomes day/night outside according to location data and when the location data is changed. Whenever these things are not happening, this script will sleep.

If you are running with geolocation enabled, it might take a few minutes for location data to become available. In most cases, location data is only available on active internet connection. Maybe... oled-linux is controlling the wrong display? If so, manually set the oled-screen value to what it should be (check config section).

If you found bugs, report them on the issues page. If you modified something, make a pull request.

There is a channel for this project on this server. If more will be required, more will be provided. Discord: https://discord.gg/t4nV3gpJbU