Called every time the mouse moves. MouseMove is called once per mouse move and is called
BEFORE any calls to OnDynamicDraw. If you are doing anything that takes a long time,
periodically call InterruptMouseMove() to see if you should stop. If the view is such
that the 2d screen point can't be mapped to a 3d point, the 'point' argument will be Unset.
RhinoCommon (in RhinoCommon.dll)
Syntax Version Information
Rhino for MacSupported in: 5.4
Rhino for WindowsSupported in: 6.27