crossing
Provided the crossingPointOnTail that an agent has reached (or will reach), this method computes the point belonging to the boundary of head that the agent should point towards to cross the passage (i.e. the first point belonging to head's boundary that is encountered by throwing a ray from crossingPointOnTail along passageShapeOnTail's normal direction). Note that the returned point may not be formally contained in head depending on the definition of insideness used by ConvexPolygon.contains, prefer using ConvexPolygon.containsBoundaryIncluded.