Kinda-sort-of-a-fix to wacom tablets behaving oddly in relative/mouse mode in KDE-wayland.

So tablets have two issues here. One is that each device seems to have its own location saved and the pointer teleports to it when it switches back from the tablet to the mouse (But not the other way around???) and this behavior gets EXTREMELY shitty when both are sending signals at once. Think a dragon ball z fight, pointer teleporting spastically all over the screen at the speed of the polling updates.

The second is the pointer moves slower with the tablet, significantly so, to the point that I need to drag my pen across the whole tablet several times over to get from a corner to the other in a 1920x1080 screen.

While I still haven't found a fix for the teleporting issue (Maybe multicursors would remove that factor? Still haven't dug into it) the speed was easy enough to fix using help from this post. I went to the apropriate event folder and set pointerAcceleration to 1, which I think makes the tablet use the same settings as the mouse. I didn't find any property to set a custom one, but this works well enough for me.

Since it's more complicated than the qt dbus explorer and I'll probably come looking for this in the future myself and want to script it, and it took me a minute to figure out how the command works, the way to get the property via the command line is

 busctl --user get-property org.kde.KWin /org/kde/KWin/InputDevice/event4 org.kde.KWin.InputDevice pointerAcceleration 

where event4 changes depending on the device number per the output of sudo libinput list-devices. It can probably get grepped and scripted easy enough, but I haven't tried myself yet.