CGAL 5.4  2D Boolean Operations on Nef Polygons Embedded on the Sphere

#include <CGAL/Nef_polyhedron_S2.h>
An object p
of type Sphere_point<R>
is a point on the surface of a unit sphere.
Such points correspond to the nontrivial directions in space and similarly to the equivalence classes of all nontrivial vectors under normalization.
Operations
Access to the coordinates is provided by the following operations. Note that the vector \( (x,y,z)\) is not normalized.
Types  
typedef unspecified_type  RT 
ring number type.  
Creation  
Sphere_point ()  
creates some sphere point.  
Sphere_point (RT x, RT y, RT z)  
creates a sphere point corresponding to the point of intersection of the ray starting at the origin in direction \( (x,y,z)\) and the surface of \( S_2\).  
Operations  
RT  x () 
the \( x\)coordinate.  
RT  y () 
the \( y\)coordinate.  
RT  z () 
the \( z\)coordinate.  
bool  operator== (const Nef_polyhedron_S2< Traits >::Sphere_point &q) 
Equality.  
bool  operator!= (const Nef_polyhedron_S2< Traits >::Sphere_point &q) 
Inequality.  
Sphere_point  antipode () 
returns the antipode of p .  