Plasma Wayland Showstoppers - Gamma

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?

https://community.kde.org/Plasma/Wayland_Showstoppers

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.

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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.

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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. :slight_smile:

Example code :
colormgr device-add-profile DP-3 icc-5aaa35b94b9b3a80352a409fc9320352