Streaks appearing from last touched location after panning

[kelvinwop]

when you draw something, pan and then draw again using the touchscreen, it draws a streak:

Basic system details

MyPaint version: 1.2.1+gitexport.bcf5a28d (Python 2.7.13, GTK 3.22.7, GdkPixbuf 2.36.4, Cairo 1.15.4, GLib 2.50.1)
Operating system: Windows 8.1, surface pro 3

Steps to reproduce

*using surface pro 3, capacitive stylus on touchscreen.

1. Start MyPaint
2. draw something (using the touchscreen, does NOT happen with mouse), freedraw tool
3. pan, occurs using any of my pan hotkeys
4. draw again. a line will appear connecting the endpoint of line 1 to the start point of line 2, may be curved if smoothing is non-zero.

Backtraces or error messages

None

[kelvinwop]

Additional tests:
Does NOT occur if you pan using the mouse. Panning with the stylus/finger causes the streaking, but from the endpoint of the last drawing. You can do whatever in panning mode (do a circles, crazy stuff) and it won't track from there, only from the last point drawn using freedraw.

[briend]

I would start with trying an alpha build: read this thread for details:

https://community.mypaint.org/t/where-to-download-windows-alpha-builds-of-mypaint/886

[kelvinwop]

Oh boy, we're already on 1.3?

[kelvinwop]

does updating keep keybinds?

[kelvinwop]

nope, didn't fix.
version:
1.3.0-alpha+git.aefccd44

(Python 2.7.14, GTK 3.22.21, GdkPixbuf 2.36.10, Cairo 1.15.6, GLib 2.54.0)

[achadwick]

So this is stylus really, not strictly a touchscreen device. I guess. Surface Pro hardware is still poorly supported by GTK.

What brush is that? @kelvinwop you getting any pressure sensitivity at all?

We might be able to break the stroke on pan keystrokes. They're not that useful for drawing 😄

[achadwick]

^ [There is basically no touchscreen/multitouch support in Windows GTK (all is WINTAB, not Tablet PC API or Windows Ink), so by exclusion...]

[kelvinwop]

Oh, I'm just using a capacitive stylus, so no pressure sensing. The brush is the mechanical pencil one. I have the opacity scaled up which is why it looks like that :-)

[AtsusaKaneytza]

I'm also still experiencing this issue with version 1.2.0 on my Laptop with my Yiynova tablet. This issue is almost non-existent on my MS Surface tablet using version 1.2.1.