Lines are connected sometimes while writing quickly with pen input

[albsch]

Is your feature request related to a problem? Please describe.

Currently, I have to be very patient when using my pen.
When I start writing, if I do it too fast, it connects the previous line with the current line. This does not happen with finger input.
I attached a screenshot of the problem.

Describe the solution you'd like

I haven't found anything in the configuration, maybe some options to ignore the first X ms or Y length of the input would fix this.

Describe alternatives you've considered

The alternative is to come close to the screen with the pen, until the screen shows the pointer. Then I can start drawing without these intermediate connecting lines.

Additional context

I'm using the current master branch and compiled from source.

[bk138]

The only idea I have is that d2ec1ac might be the culprit - can you revert this commit, re-build and try again? Otherwise, I suspect a hardware flaw (does this happen in other apps?).

[albsch]

I have reverted the commit, but the behavior stays the same.
I enabled the debug print, and it seems the coordinates are wrong even before the lines that I reverted. It seems to be the last position when I lift up the pen, and only during the on_motion function the coordinates are correct.

If I prevent the on_buttonpress function to add its coordinates to the queue, the first stroke works as expected. Whereas before, this artifact happens on the first touch of the pen. But then the artifacts happen again on all following strokes. Is there some event left over in the event queue somewhere?

I tried a few drawing apps and this is the first time a behavior like this is happening with the pen. I don't think it's a hardware issue.

[bk138]

Mhh, seems complicated - you might try some older git revision by chance and see if it works there and then git-bisect your way to the flaky commit - I don't have a better idea, sorry for that :-/
The project and me will be thankful if you decide to take up the task :-)