GNOME Bugzilla – Bug 759463
Touchscreen input in HiDPI gives wrong coordinates
Last modified: 2015-12-14 23:20:09 UTC
XWayland windows are fine. I think that the coordinates simply need to be scaled by the scaling factor. I wrote a simple app to show touches and gestures (https://github.com/benwaffle/GTK-Gestures)
This is a mutter bug.
Should be fixed by https://git.gnome.org/browse/mutter/commit/?id=91ac69382d5c6e9675c360e7f8f93aa362a191e0