4

In the CLI, xrandr --output MONITOR_NAME --brightness 0.7 seemingly "works" because no feedback is shown.

After using xrandr --verbose | grep Brightness, Brightness: 0.70 is shown as output but no visual changes occured.

I rebooted the system to check if this was needed but no. An other xrandr --verbose | grep Brightness later, Brightness: 0.0 is shown.

Could this be related to my monitor being 'WAYLAND0'? If so, is there a way to change that? I run a Linux Mate 20 on the side, and my very same monitor is displayed as 'VGA-1' there, and xrandr works fine.

Thank you!

Edit: I went to /etc/gdm3/custom.conf and removed the # from #WaylandEnable=false, which gave me back the 'VGA-1' output after a reboot.

2 Answers2

0

I ended up here after having the same problem, I had created a script using xrandr to control brightness that no longer works with Wayland.

This is not a complete answer, although what I've found so far might help you.

The alternative to xrandr in Wayland is wlr-randr, which for some reason is not working for me in Ubuntu 22.04 due to the following error:

compositor doesn't support wlr-output-management-unstable-v1

Another alternative written in rust, does have the brightness functionality implemented but only in a test branch, see this issue.

You might find yourself looking for other functionalities or tools in Wayland, so I'll leave this other link if needed.

I'll edit this answer if I get this working somehow.

Nicolas
  • 253
0

xrandr failed to set the brightness for my external display too. I found a workaround in another Ask Ubuntu post and it worked for me. It uses the Soft Brightness GNOME extension. See it here: https://askubuntu.com/a/1403810/1647384

spiralspree
  • 1