Hi all,

I'm trying to use Astropad (app provides OsX tablet interface with an iPad) with an app I’ve written and I'm getting odd results with tablet events in QT. First of all, I've been in contact with the devs and they seem to think it's a QT bug rather than an Astropad bug, and in any case Astropad works with other graphics programs that I've tried.

I'm coding in python using pyqt and have Python 3.5.0 and QT 5.5.0 installed.

At the level of QWidget you get an initial TabletPress event with pressure=0 followed immediately by a TabletRelease event with pressure>0 at which point the rest of the stroke is only reported as mouse events, with are low frequency and don’t contain pressure info.

Astropad:

    TabletPress: pointer=1 pressure=0.0 tilt=(27,12)
    TabletRelease: pointer=1 pressure=0.13333334028720856 tilt=(27,12)
    MousePress
    MouseMove
    MouseMove
    ...[ many MouseMove ]...
    MouseRelease

Works as you'd expect with Wacom tablet, though accepting the tablet events does't stop the mouse events being fired (minor niggle):

    TabletPress: pointer=1 pressure=0.4313725531101227 tilt=(0,0)
    MousePress
    TabletMove: pointer=1 pressure=0.45098039507865906 tilt=(0,0)
    MouseMove
    TabletMove: pointer=1 pressure=0.45098039507865906 tilt=(0,0)
    TabletMove: pointer=1 pressure=0.4470588266849518 tilt=(0,0)
    ...[ many MouseMove and many more TableMove ] ...
    TabletRelease: pointer=1 pressure=0.0 tilt=(0,0)
    MouseMove
    MouseRelease

At the level of QApplication I'm seeing TabletEnterProximity and TabletLeaveProximity events as you'd expect.

Any ideas on how to fix or work around this? It looks like QT is getting confused and is interpreting the stroke on the tablet as having lifted and falling back to default mouse handling. I've tried re-emmiting a tablet press or move event from code with no joy.

Alexei
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