Fix Steam cursor in gamescope

[TobiPeterG]

I noticed that the cursor in game mode is often not the steam cursor it should be. This fixes it. Can this be confirmed? :)

[alkazar]

This seems like it would affect desktop mode as well.

I think it would be better to use the --cursor gamescope option instead.

[TobiPeterG]

I debugged it a bit.
(starting steam with "gamescope --cursor CURSORFILE.png /usr/bin/steam")
Yes, using --cursor would be correct. The current setting can't work anymore because the image file in /home doesn't exist anymore on Steam's side.
However, I noticed that gamescope is most of the times not using the cursor one specifies (there is also a message here sometimes:

Desktop state changed: desktop: { pos:    0,   0 size: 1280, 720 } primary: { pos:    0,   0 size: 1280, 720 }
Caching cursor image for , size 10x16, serial 47, cache size = 0

This behaviour can be seen on upstream gamescope as well as gamescope-plus

Will look at this further

[TobiPeterG]

Should I open a ticket about this on their gamescope repo?

[TobiPeterG]

Changing the cursor in this file: ~/.config/gtk-3.0/settings.ini seems to have an influence though which is really weird.

[TobiPeterG]

Ah I found this issue:
ValveSoftware/gamescope#1438

So steam is actually using the GTK cursor theme no matter what we set with --cursor. So something like I propose needs to be done.

[TobiPeterG]

Alright, so I found that this is what steamOS is doing:

export XCURSOR_THEME=steam
export XCURSOR_SCALE=256

# Chromium (and therefore Steam) ignore XCursor and use on the GTK config
kwriteconfig5 --file gtk-3.0/settings.ini  --group Settings --key gtk-cursor-theme-name steam

Which is exactly what I'm injecting manually. :)