Code review comment for lp:~mir-team/mir/touchspot-visualizer

Yep, touch spot visualization is a nice feature to have eventually...

(1) It looks like we should be exposing MirMotionEvent instead of defining new structures to translate to. Spot, Action etc are redundant with MirMotionEvent which is already publicly defined. I don't think we need to define new types as it only creates the need for more translation logic.

Given a copy of the latest MirMotionEvent struct, a compositor would easily have all the information it needs to visualize the touch points. Literally just send the latest MirMotionEvent to the compositor and you're done. So I don't think the complexity of the new interfaces here is justified.