The function zone compute the zone of the given -monotone curve in the existing arrangement. Meaning, it output the arrangement's vertices, edges and faces that the -monotone curve intersects. The order of the objects is the order that they are discovered when traversing the -monotone curve from left to right.
A given point-location object is used for answering point-location queries during the insertion process. By default, the function uses the ``walk along line'' point-location strategy - namely an instance of the class Arr_walk_along_line_point_location<Arrangement_2<Traits,Dcel> >.
#include <CGAL/Arrangement_2.h>
Precondition
If provided, pl must be attached to the given arrangement arr.