Jcg.triangulations2D

Class TriangulationDS_2<X extends Point_>

java.lang.Object

Jcg.triangulations2D.TriangulationDS_2<X>

public class TriangulationDS_2<X extends Point_>
extends java.lang.Object

Data structure for representing 2D triangulations that uses the standard face/vertex encoding, represented by classes TriangulationDSFace_2 and TriangulationDSVertex_2 respectively. In this representation we store the collection of faces as well as the collection of vertices of the triangulation. Each face provides access to its vertices and neighboring faces, while each vertex provides access to one of its incident faces.

Author:

Luca Castelli Aleardi and Steve Oudot

Field Summary

Fields

Modifier and Type	Field and Description
java.util.ArrayList<TriangulationDSFace_2<X>>	faces
java.util.ArrayList<TriangulationDSVertex_2<X>>	vertices

Constructor Summary

Constructors

Constructor and Description
TriangulationDS_2() creates an empty triangulation data structure.
TriangulationDS_2(int nFaces, int nVertices) creates an empty triangulation data structure with prescribed numbers of faces and vertices.
TriangulationDS_2(X[] points, int[][] neighbors) Create a triangulation DS from a vertex shared mesh representation It takes linear space and linear time.

Method Summary

Modifier and Type	Method and Description
boolean	areEqual(TriangulationDSFace_2<X> face1, int i1, TriangulationDSFace_2<X> face2, int i2) checks whether an edge is shared by two faces f1 and f2: the function check whether the corresponding vertices appear both in f1 and f2, in the correct order.
TriangulationDSFace_2<X>	createFace() creates a new face and adds it to the faces container of the triangulation data structure.
TriangulationDSFace_2<X>	createFace(TriangulationDSVertex_2<X> v1, TriangulationDSVertex_2<X> v2, TriangulationDSVertex_2<X> v3, TriangulationDSFace_2<X> c1, TriangulationDSFace_2<X> c2, TriangulationDSFace_2<X> c3) creates a new face in the triangulation, with the given incident vertices and adjacent triangles.
TriangulationDSVertex_2<X>	createVertex(X p, TriangulationDSFace_2<X> f) creates a new vertex in the triangulation, with the given incident triangle.
HalfedgeHandle<X>	flipEdge(HalfedgeHandle<X> e) flips an edge in the triangulation and returns the new edge
boolean	hasBoundary() checks whether the triangulation has a boundary.
boolean	hasFace(TriangulationDSFace_2<X> c) checks whether the triangulation contains face c.
boolean	hasVertex(TriangulationDSVertex_2<X> v) checks whether the triangulation contains vertex v.
java.util.Collection<TriangulationDSFace_2<X>>	incidentFaces(TriangulationDSVertex_2<X> v) Returns the collection of all faces incident to vertex v.
void	insertBarycenter(TriangulationDSFace_2<X> f) insert in a triangle the barycenter point of its incident vertices
TriangulationDSVertex_2<X>	insertInTriangle(X p, TriangulationDSFace_2<X> t) Inserts point p in face c.
TriangulationDSVertex_2<X>	insertOutside(X point, TriangulationDSFace_2<X> c, int i) Inserts point p outside the triangulation.
boolean	isValid() checks the combinatorial validity of the triangulation.
TriangulationDSFace_2<X>	makeTriangle(X p1, X p2, X p3) creates a triangle with vertices p1, p2, p3.
int	sizeOfFaces() returns the number of faces of the triangulation.
int	sizeOfVertices() returns the number of vertices of the triangulation.
java.lang.String	toString()

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

faces

public java.util.ArrayList<TriangulationDSFace_2<X extends Point_>> faces

vertices

public java.util.ArrayList<TriangulationDSVertex_2<X extends Point_>> vertices

Constructor Detail

TriangulationDS_2

public TriangulationDS_2()

creates an empty triangulation data structure.

TriangulationDS_2

public TriangulationDS_2(int nFaces,
                         int nVertices)

creates an empty triangulation data structure with prescribed numbers of faces and vertices.

TriangulationDS_2

public TriangulationDS_2(X[] points,
                         int[][] neighbors)

Create a triangulation DS from a vertex shared mesh representation It takes linear space and linear time.

Method Detail

createFace

public TriangulationDSFace_2<X> createFace()

creates a new face and adds it to the faces container of the triangulation data structure.

sizeOfVertices

public int sizeOfVertices()

returns the number of vertices of the triangulation.

sizeOfFaces

public int sizeOfFaces()

returns the number of faces of the triangulation.

Returns:

hasFace

public boolean hasFace(TriangulationDSFace_2<X> c)

checks whether the triangulation contains face c.

Parameters:

c -

Returns:

hasVertex

public boolean hasVertex(TriangulationDSVertex_2<X> v)

checks whether the triangulation contains vertex v.

hasBoundary

public boolean hasBoundary()

checks whether the triangulation has a boundary.

createVertex

public TriangulationDSVertex_2<X> createVertex(X p,
                                               TriangulationDSFace_2<X> f)

creates a new vertex in the triangulation, with the given incident triangle.

createFace

public TriangulationDSFace_2<X> createFace(TriangulationDSVertex_2<X> v1,
                                           TriangulationDSVertex_2<X> v2,
                                           TriangulationDSVertex_2<X> v3,
                                           TriangulationDSFace_2<X> c1,
                                           TriangulationDSFace_2<X> c2,
                                           TriangulationDSFace_2<X> c3)

creates a new face in the triangulation, with the given incident vertices and adjacent triangles.

flipEdge

public HalfedgeHandle<X> flipEdge(HalfedgeHandle<X> e)

flips an edge in the triangulation and returns the new edge

areEqual

public boolean areEqual(TriangulationDSFace_2<X> face1,
                        int i1,
                        TriangulationDSFace_2<X> face2,
                        int i2)

checks whether an edge is shared by two faces f1 and f2: the function check whether the corresponding vertices appear both in f1 and f2, in the correct order. LCA: a' tester

incidentFaces

public java.util.Collection<TriangulationDSFace_2<X>> incidentFaces(TriangulationDSVertex_2<X> v)

Returns the collection of all faces incident to vertex v.

isValid

public boolean isValid()

checks the combinatorial validity of the triangulation.

makeTriangle

public TriangulationDSFace_2<X> makeTriangle(X p1,
                                             X p2,
                                             X p3)

creates a triangle with vertices p1, p2, p3.

insertInTriangle

public TriangulationDSVertex_2<X> insertInTriangle(X p,
                                                   TriangulationDSFace_2<X> t)

Inserts point p in face c. Face c is split into 3 triangles.

insertOutside

public TriangulationDSVertex_2<X> insertOutside(X point,
                                                TriangulationDSFace_2<X> c,
                                                int i)

Inserts point p outside the triangulation. A new triangle is added and attached to a boundary triangle c (they share the edge opposite to vertex i in c).

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

insertBarycenter

public void insertBarycenter(TriangulationDSFace_2<X> f)

insert in a triangle the barycenter point of its incident vertices