06-12-2020, 03:47 PM
(This post was last modified: 06-12-2020, 11:52 PM by Dendrocalamus64.)
I spent quite a while getting Manjaro 20.04 + KDE running on an SD card yesterday so I could test this. It's mostly time-consuming because of the volume of data to be downloaded; 1GB compressed image + ~800MB package updates, over "pandemic" internet that keeps stalling out.
Can confirm that KDE Night Color doesn't do anything, and redshift -m drm gives the error above.
This file is also 0 bytes on MrFixIt Debian+MATE, yet redshift -m drm works here.
---
http://jonls.dk/redshift/
Looks like an issue with the video driver on both stock Debian & stock Manjaro. Anything trying to affect the gamma through xrandr therefore won't work until that feature is added to the video driver.
You can test this from the command line with xrandr.
$ xrandr --current
to get the display name (e.g. eDP-1), then
$ xrandr --output eDP-1 --gamma red:green:blue
and see if it does nothing.
Gnome uses something called "Wayland", and reading around, I am told,
"Actually no program can support Wayland to change color temperatures except for the compositor."
"GNOME's implementation is tied to the compositor (because of restrictions Wayland puts in place)"
(source)
so Gnome Night Light works on Manjaro because it's doing something completely different.
https://www.kernel.org/doc/html/v4.12/gp...c.drm_crtc
redshift -m drm is erroring out when it sees that gamma_size is <= 1.
The table being that small means that drm does not actually know of a gamma ramp for the device.
My guess is that with the many changes Manjaro made to the direct rendering manager, they ended up disabling gamma correction as something to be re-added in the future.
Can confirm that KDE Night Color doesn't do anything, and redshift -m drm gives the error above.
Code:
/sys/devices/platform/display-subsystem/drm/card0/card0-eDP-1/edidThis file is also 0 bytes on MrFixIt Debian+MATE, yet redshift -m drm works here.
---
http://jonls.dk/redshift/
Quote:Known bugs and limitations
* Certain video drivers do not support adjustable gamma ramps. In some cases Redshift will fail with an error message, but other drivers silently ignore adjustments to the gamma ramp.
Looks like an issue with the video driver on both stock Debian & stock Manjaro. Anything trying to affect the gamma through xrandr therefore won't work until that feature is added to the video driver.
You can test this from the command line with xrandr.
$ xrandr --current
to get the display name (e.g. eDP-1), then
$ xrandr --output eDP-1 --gamma red:green:blue
and see if it does nothing.
Gnome uses something called "Wayland", and reading around, I am told,
"Actually no program can support Wayland to change color temperatures except for the compositor."
"GNOME's implementation is tied to the compositor (because of restrictions Wayland puts in place)"
(source)
so Gnome Night Light works on Manjaro because it's doing something completely different.
https://www.kernel.org/doc/html/v4.12/gp...c.drm_crtc
redshift -m drm is erroring out when it sees that gamma_size is <= 1.
The table being that small means that drm does not actually know of a gamma ramp for the device.
My guess is that with the many changes Manjaro made to the direct rendering manager, they ended up disabling gamma correction as something to be re-added in the future.
