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The class Triangulation_data_structure_2<Vb,Fb> is a model for the TriangulationDataStructure_2 concept. It can be used to represent an orientable 2D triangulation embedded in a space of any dimension.
The vertices and faces are stored in two nested containers, which are implemented using CGAL::Compact_container. The class may offer some flexibility for the choice of container in the future, in the form of additional template parameters.
#include <CGAL/Triangulation_data_structure_2.h>
In addition to the interface documented in the concept, the class offers the following types and functions.
| typedef CGAL::Compact_container<Vertex> | ||
| Vertex_range; | Vertex container type. | |
| typedef CGAL::Compact_container<Face> | ||
| Face_range; | Face container type. | |
In addition to the modifiers required by the TriangulationDataStructure_2 concept, the Triangulation_data_structure_2<Vb,Fb> class supports also the modifiers below. Note also that the modifiers below guarantee the combinatorial validity of the resulting data structure.
| Vertex_handle | tds.join_vertices ( Face_handle f, int i) | |||
Joins
the vertices that are endpoints of the edge (f,i). It returns
a vertex handle to common vertex (see
Fig. 38.6).
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| Vertex_handle | tds.join_vertices ( Edge e) | Joins the vertices that are endpoints of the edge e. It returns a vertex handle to common vertex. | ||
| Vertex_handle | tds.join_vertices ( Edge_iterator eit) | |||
| Joins the vertices that are endpoints of the edge *eit. It returns a vertex handle to common vertex. | ||||
| Vertex_handle | tds.join_vertices ( Edges_circulator ec) | |||
| Joins the vertices that are endpoints of the edge *ec. It returns a vertex handle to common vertex. | ||||
| boost::tuples::tuple<Vertex_handle, Vertex_handle, Face_handle, Face_handle> | ||||
| tds.split_vertex ( Vertex_handle v, Face_handle f1, Face_handle f2) | ||||
Splits the vertex v into two vertices v1 and
v2. The common faces f and g of v1 and
v2 are created after (in the counter-clockwise sense) the
faces f1 and f2. The 4-tuple (v1,v2,f,g) is
returned (see Fig. 38.6).
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| Vertex_handle | tds.insert_degree_2 ( Face_handle f, int i) | |||
| Inserts a degree two vertex and two faces adjacent to it that have two common edges. The edge defined by the face handle f and the integer i is duplicated. It returns a handle to the vertex created (see Fig. 38.7). | ||||
| void | tds.remove_degree_2 ( Vertex_handle v) | |||
Removes a degree 2
vertex and the two faces adjacent to it. The two edges of the star of
v that are not incident to it are collapsed
(see Fig. 38.7).
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