Track infra red basically.
AH2 now natively supports it which means much smoother operation and it always returns to the dead ahead view position.
If you dont know what TrackIR is you really should, as once setup and working correctly as you move your head the view does same.
So move your head left, and view smoothly pans left or up/ down etc.
Lol at least it did work until i altered some setings will need to reinstall AH2 now i think
