colour temperature setting raspberry pi 3

I would like to adjust the colour temperature on the desktop. (In case you’re not sure what this is, this is what applications like F.lux, redshift, and nightlight do on windows, linux, and mac os.)

What is required to do this at a SWI / driver level via RISC OS on a Raspberry PI 3 (BCM2837) ?

Not sure. Maybe any of the “Monitor calibration Tools” like Gamma helps.

Gamma looks like it has got the right calculations, but on my system it is only affecting the colours of the pointer — not the actual contents of the desktop.

Mmm, works on RPCEmu and Titanium but not on Pi3B+ PiTop.
Have a second Tool called Minitor on NAS, I’m sure (not found on www). Will search and try later.

Try Monitor …

Thank you, I’m (manually) demangling the BASIC now (“Squashed by StrongBS 2.10” …)

!Gamma will work on things which emulate the VIDC2 LUT (look up tables). I had assumed this was all the newer machines. I’ve currently only got RISC OS on an Iyonix and ARMx6 Mini.m, but I have a spare Raspberry Pi 3 knocking about, so I’ll set that up, and see what is going on.