I believe gamma control is being worked on for Wayland, but I’m sure it was marked as a Showstopper on this status page, - now it seems to have disappeared?
For those of us who are visually impaired and rely on gamma control to make poorly calibrated screens readable (ASUS VS248QE is a prime example, where 60Hz is perfectly calibrated, but 144Hz is a hazy mess unless gamma is set manually), I’ve been using xrandr on xorg.
Are there any updates for progress on Wayland? It’s literally the only thing left stopping me from moving across.
A huge thanks for all the excellent work, day in day out, that goes on behind the scenes, that people don’t always see unless they’re subscribed to lists on invent.kde.org!
This was just merged which if you have a calibration for the display with a VCGT tag in it you can now apply it to the plasma 6 session as long as youre ok with sRGB output. You might be able to make a profile with VCGT tag without a colorimeter but i cant vouch for the results of that.
there might be other gamma shenanigans which im not aware of that have been merged which let you do other things besides this as well. Ive only been keeping up on this MR and its company for this specific use case.
This is wonderful news, and thank you for your exhaustive testing, it’s deeply appreciated!
[Addendum, I’ve also found this link incredibly helpful ; ICC profiles - ArchWiki] in particular the section on applying icc/icm profiles to a device that’s clearly stated in Section 3.4
That link does not apply to the current implementation in Kwin unfortunately. Ill do a guide on how to use what we have in regards to icc profiles and how to test/verify its working soon as it doesnt use colord and displaycal has to be used in a specific way because displaycal isnt yet ready for this work on wayland.
as for gamma adjustments outside this i cant say as i dont do adjustments without a colorimeter and havent been keeping up on it.
I found that using colormgr to append the icm profile to the device absolutely made a significant difference to colour values in Wayland. While it’s not a manual solution for gamma and I can’t tweak values (yet), and I fully get it’s not applicable to the current implementation, it’s definitely a step in improving the situation.
Example code :
colormgr device-add-profile DP-3 icc-5aaa35b94b9b3a80352a409fc9320352
I just found a repo with sRGB-ICM files with different gamma values that worked for me to set my gamma as long as this isn’t possible directly from plasma settings.
I’ve been able to manually install the ICM profile via the GUI in Plasma 6, - great to see that we’re making progress. Looking forward to seeing gamma become correctable beyond the cli in the future.
(have to mangle links because otherwise I get An error occurred: Sorry, you can’t include links in your posts.)
That repository’s owner has also written a tutorial about leverages these ICC profiles to change a display’s brightness: ///www.reddit.com/r/kde/comments/15nxxhq/wayland_how_to_adjust_per_monitor_gamma/ .
While still cumbersome, this is the only solution/workaround known to me to change display brightness in my setup (Debian 12, KDE Plasma 5.27.5, Wayland); my displays (built-in Framework 13 AMD laptop display and external Samsung M7 monitor) don’t support DDC, and even on their lowest hardware-provided brightness settings they are still retina-burning bright at night and therefore call for an additional software-emulated dimming overlay.
Unfortunately, Plasma 5’s built-in Night Color only emulates color temperature, not brightness; all Plasma 5 Desktop Effects/Plasmoids/Community Addons for dimming/brightness control I checked either use DDC or emulate brightness dimming via (legacy) XServer randr - none of which are applicable in my Wayland setup.
I noticed Plasma 5 includes a Wayland protocol named contrast, which includes requests such as set_intensity, as well as set_frost (with arguments red, green, blue, and alpha) (also see its Wayland Explorer documentation). Maybe by leveraging these it is possible to emulate gamma, brightness and dimming under a Plasma 5 with Wayland?
