CGAL 5.1.3 - 2D Boolean Operations on Nef Polygons Embedded on the Sphere
CGAL::Nef_polyhedron_S2< Traits >::SHalfloop Class Reference

#include <CGAL/Nef_polyhedron_S2.h>

## Definition

A sloop is a great circle on a sphere.

A shalfloop is an oriented sloop. It is always paired with a shalfloop whose supporting Sphere_circle is pointing in the opposite direction. The twin() member function returns this shalfloop of opposite orientation. Each Nef_polyhedron_S2 can only have one sloop (resp. two shalfloops).

The figure below depicts the relationship between a shalfloop and sfaces on a sphere map.

Incidences of an SHalfloop
Creation

There is no need for a user to create a SHalfloop explicitly. The class Nef_polyhedron_S2<Traits> manages the needed shalfloops internally.

CGAL::Nef_polyhedron_S2::SFace
CGAL::Nef_polyhedron_S2::Sphere_circle

## Types

The following types are the same as in Nef_polyhedron_S2<Traits>.

typedef unspecified_type Mark
type of mark.

typedef unspecified_type Sphere_circle
sphere circle type stored in SHalfloop.

typedef unspecified_type SHalfloop_const_handle
const handle to SHalfloop.

typedef unspecified_type SFace_const_handle
const handle to SFace.

## Operations

const Markmark () const
the mark of the halfloop.

const Sphere_circlecircle () const
the sphere circle of the halfloop.

SHalfloop_const_handle twin () const
the twin of the halfloop.

SFace_const_handle incident_sface () const
the incident sface of the halfloop.