A color temperature setting library and CLI that operates in a similar way to f.lux and Redshift.

The command line app automatically determines your location using GeoIP and adjusts the color temperature depending on time.

For wayland support replace all commands with waysct instead of sct.

# For X11 and Windows
$ go install github.com/d4l3k/go-sct/cmd/sct@latest

$ sct # Launch in background
$ sct 3000 # One time temperature change. Temperature must be 1000-10000.

# For Wayland
$ go install github.com/d4l3k/go-sct/cmd/waysct@latest

$ waysct # Launch in background
$ waysct 3000 # One time temperature change. Wayland requires a persistent manager so this will immediately revert.

By default, the lowest color temperature allowed is around 4500K. More information is available here

There is a workaround to allow all possible adjustments by alterting the registry.

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ICM]
"GdiIcmGammaRange"=dword:00000100

Save the above as a file with a ".reg" extension and double click to apply.

Setting the color temperature uses a port of sct in Go. Credit goes to him for figuring out how to do this.

go-sct also provides the geoip package which is a packaged version of http://devdungeon.com/content/ip-geolocation-go

Made by Tristan Rice.

go-sct is licensed under the MIT license. geoip and sct are copyrighted by their respective owners.

waysct is using code from the redshift implementation and is licensed under GPLv3. See https://github.com/minus7/redshift/commit/7da875d34854a6a34612d5ce4bd8718c32bec804