vtkRenderWindowInteractor GetPointersDownCount() is always 0 for multitouch

Hi, I’m trying to pass qt5 touch event (QTouchEvent) to vtkRenderWindowInteractor. I loop over all touchs points and send x,y, pointerIndex as event information to the interactor.

I send the command correspondingly like this:
Qt::TouchPointPressed: vtkCommand::LeftButtonPressEvent;
Qt::TouchPointMoved: vtkCommand::MouseMoveEvent;
Qt::TouchPointReleased: vtkCommand::LeftButtonReleaseEvent;

None of the gestures are working. I have recognize gestures turned on. I confirmed that the touch points are being sent correctly, but GetPointersDownCount() always returns 0. Seems like the interactor never start to recognize any touch points for gestures. Why is that?