is_occupied(chairloc, actor))
is_occupied(sitloc, actor))
int Sit_actor_action::handle_event	(	Actor *actor	)	{	if (get_index() == 0 &&		// First time?	    is_occupied(chairloc, actor))		return 0;		// Abort.	return Frames_actor_action::handle_event(actor);	}