Erratic tilt direction with pen/tablet inputs
Affected Version
OS: Arch Linux GNOME 40.4.0 mutter 40.5-1
Bug Summary
When I use a pen/tablet device with tilt support, the tilt direction appears unstable and erratic on GNOME Wayland (see attached image). The tilt works properly with Sway window manager or GNOME Xorg. Also, I could reproduce the issue on different machines with different pen/tablet devices (Wacom Cintiq and Lenovo AES Pen). It doesn't seem to matter what graphics program I use; Krita, GIMP, and MyPaint are all affected in the same way. I haven't changed any pen/tablet settings through GNOME settings, xsetwacom, etc.
I thought the problem was related to a libinput bug I reported a while back, but some debugging indicated the erratic tilt was likely a separate mutter bug. Here's a link to that conversation: https://gitlab.freedesktop.org/libinput/libinput/-/issues/632#note_997666.
I know the problem started after an update earlier this year, but unfortunately I can't remember how many months ago that was.
Steps to Reproduce
- Log into a GNOME Wayland session
- Open a graphics editor (e.g. Krita) and select a brush that uses tilt
- Draw on the canvas.
For systems without pen input, I made a recording of the input
events when I drew the attached example image using libinput record,
which can be replayed with sudo libinput replay erratic-tilt.yml.
What happened
The tilt direction appears to flip around erratically.
What did you expect to happen
The tilt direction should reflect the actual orientation of the stylus.
Relevant logs, screenshots, screencasts etc.
Example
