Looks like SwayOSD doesn’t work with external monitors using DDC/CI

[jjramsey]

I'm a member of the "video" group but have an external monitor. SwayOSD doesn't change the brightness of my monitor.

The utility "ddcutil" does work on my monitor.

Here are the issues I saw, FWIW.

Changing screen brightness on KDE 6.1 (without using SwayOSD) works, even though /sys/class/backlight/ is empty. SwayOSD doesn't work for the purpose, though. Looks like KDE 6.1 can use DDC/CI as a backend.

When brightnessctl is installed, the OSD shows up; it just doesn't show any change in brightness. Without brightnessctl, there's no OSD for brightness at all. Note that brightnessctl requires the out-of-tree kernel driver ddcci-driver-linux to work with external monitors.

BTW, I had been using Labwc with the following keybinding config:

    <keybind key="XF86AudioMute">
      <action name="Execute"
              command="swayosd-client --output-volume mute-toggle"/>
    </keybind>
    <keybind key="XF86AudioRaiseVolume">
      <action name="Execute" command="swayosd-client --output-volume raise"/>
    </keybind>
    <keybind key="XF86AudioLowerVolume">
      <action name="Execute" command="swayosd-client --output-volume lower"/>
    </keybind>
    <keybind key="XF86MonBrightnessUp">
      <action name="Execute" command="swayosd-client --brightness raise"/>
    </keybind>
    <keybind key="XF86MonBrightnessDown">
      <action name="Execute" command="swayosd-client --brightness lower"/>
    </keybind>

[SoulHarsh007]

👋 I think you can try passing the device manually to swayosd-client, I was able to change brightness for a single monitor, but passing the device lets me change it for my other monitor as well. You can check the device ID using brightnessctl --list --class backlight and then passing it to swayosd-client as swayosd-client --device="<DEVICE_ID>".

[SherLock707]

I use ddcutil to control my external monitor brightness. would be great if I can use that backend somehow...

Or I can handle the brightness just need brightness OSD to popup where I can specify the brightness level. (can we have a dummy volume and brightness OSD which can show progress bar based on values used in the command?)
swayosd-client --brightness fake 20
swayosd-client --output-volume fake 50
swayosd-client --output-volume fake 0