CGAL 6.0.1  3D Triangulation Data Structure

#include <CGAL/Triangulation_utils_3.h>
Inherited by CGAL::Triangulation_3< Traits, Delaunay_triangulation_3< Traits, TDS, LP >::Triangulation_data_structure, SLDS >, CGAL::Triangulation_3< typename Traits, typename TDS, typename SLDS >, and CGAL::Triangulation_data_structure_3< VertexBase, CellBase, ConcurrencyTag >.
The class Triangulation_utils_3
defines operations on the indices of vertices and neighbors within a cell.
Operations  
static unsigned int  next_around_edge (unsigned int i, unsigned int j) 
In dimension 3, index of the neighbor n that is next to the current cell, when turning positively around an oriented edge whose endpoints are indexed i and j .  
static int  vertex_triple_index (const int i, const int j) 
In dimension 3, index of the j 'th vertex in counterclockwise order on the face opposite to vertex with i of the cell.  
static unsigned int  ccw (unsigned int i) 
Has a meaning only in dimension 2.  
static unsigned int  cw (unsigned int i) 
Same for clockwise.  

static 
Has a meaning only in dimension 2.
Computes the index of the vertex that is next to the vertex numbered i
in counterclockwise direction. (see Figure 47.1).
i<3
.

static 
In dimension 3, index of the neighbor n
that is next to the current cell, when turning positively around an oriented edge whose endpoints are indexed i
and j
.
According to the usual numbering of vertices and neighbors in a given cell, it is also the index of the vertex opposite to this neighbor n
. (see Figure 47.1).
( i < 4 ) && ( j < 4 ) && ( i != j )
.

static 
In dimension 3, index of the j
'th vertex in counterclockwise order on the face opposite to vertex with i
of the cell.
( i < 4 ) && ( j < 3 )
.