Thanks a lot for the nice 3D WPF framework.
Following to this question..

I'm trying to extend the overlay example and trying to capture the event from both the HelixViewPort3D and the overlay canvas. When I turn the IsHitTestVisble to True, the viewport will not be able to capture any interaction events. How can I make both HelixViewPort3D and overlay canvas capture the events?

Thanks a lot!!