WLR gamma-control broken on main

[tomKPZ]

Hyprland built at 738ec90

I cloned the wlroots repo and built examples/gamma-control.c. When running build/examples/gamma-control -b 0.5 to set brightness to 50%, the command fails on Hyprland with failed to set gamma table. The command succeeds with Sway.

[vaxerski]

sway or sway-git?

[tomKPZ]

sway-git

[vaxerski]

is this still a thing?

[m-bartlett]

is this still a thing?

I came to report a bug I'm observing with a similar issue as OP, and found this open issue.

I often use gammastep to control screen brightness at night through gamma correction. Recently I am only able to run one app that performs gamma correction per Hyprland login, and afterward all other processes that attempt to correct gamma fail with similar errors:

$ gamma-control -b 1
failed to set gamma table
$ gammastep -o -b 1.0:0.66
Warning: Zero outputs support gamma adjustment.
Warning: 1/1 output(s) do not support gamma adjustment.

When I exit the Hyprland session and re-login I can run gammastep or gamma-control with gamma correction flags once but then I get the same errors for all executions after the first run.

The version I'm currently running is:

$ hyprctl version
Hyprland, built from branch  at commit cba1ade848feac44b2eda677503900639581c3f4 dirty (props: bump version to 0.40.0).
Date: Sat May 4 09:42:32 2024
Tag: v0.40.0, commits: 4606

flags: (if any)

[hashdefault]

I tried a lot of piece of softwares like wlsunset, gammastep and get the same errors, but hyprsunset solved for me:

sudo pacman -S hyprsunset

hyprsunset -t 4500