com.vividsolutions.jts.triangulate.quadedge
Class QuadEdgeTriangle

java.lang.Object
  extended by com.vividsolutions.jts.triangulate.quadedge.QuadEdgeTriangle

public class QuadEdgeTriangle
extends java.lang.Object

Models a triangle formed from Quadedges in a Subdivision. Provides methods to access the topological and geometric properties of the triangle. Triangle edges are oriented CCW.

Version:
1.0
Author:
Martin Davis

Constructor Summary
QuadEdgeTriangle(QuadEdge[] edge)
           
 
Method Summary
 boolean contains(Coordinate pt)
           
static boolean contains(QuadEdge[] tri, Coordinate pt)
          Tests whether the point pt is contained in the triangle defined by 3 QuadEdgees.
static boolean contains(Vertex[] tri, Coordinate pt)
          Tests whether the point pt is contained in the triangle defined by 3 Vertexes.
 QuadEdgeTriangle getAdjacentTriangleAcrossEdge(int edgeIndex)
           
 int getAdjacentTriangleEdgeIndex(int i)
           
 Coordinate getCoordinate(int i)
           
 Coordinate[] getCoordinates()
           
 QuadEdge getEdge(int i)
           
 int getEdgeIndex(QuadEdge e)
          Gets the index for the given edge of this triangle
 int getEdgeIndex(Vertex v)
          Gets the index for the edge that starts at vertex v.
 QuadEdge[] getEdges()
           
 void getEdgeSegment(int i, LineSegment seg)
           
 Geometry getGeometry(GeometryFactory fact)
           
 QuadEdgeTriangle[] getNeighbours()
          Gets the neighbours of this triangle.
 java.util.List getTrianglesAdjacentToVertex(int vertexIndex)
           
 Vertex getVertex(int i)
           
 Vertex[] getVertices()
          Gets the vertices for this triangle.
 boolean isBorder()
          Tests whether this triangle is adjacent to the outside of the subdivision.
 boolean isBorder(int i)
           
 boolean isLive()
           
 void kill()
           
static int nextIndex(int index)
          Finds the next index around the triangle.
static Geometry toPolygon(QuadEdge[] e)
           
static Geometry toPolygon(Vertex[] v)
           
 java.lang.String toString()
           
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Constructor Detail

QuadEdgeTriangle

public QuadEdgeTriangle(QuadEdge[] edge)
Method Detail

contains

public static boolean contains(Vertex[] tri,
                               Coordinate pt)
Tests whether the point pt is contained in the triangle defined by 3 Vertexes.

Parameters:
tri - an array containing at least 3 Vertexes
pt - the point to test
Returns:
true if the point is contained in the triangle

contains

public static boolean contains(QuadEdge[] tri,
                               Coordinate pt)
Tests whether the point pt is contained in the triangle defined by 3 QuadEdgees.

Parameters:
tri - an array containing at least 3 QuadEdges
pt - the point to test
Returns:
true if the point is contained in the triangle

toPolygon

public static Geometry toPolygon(Vertex[] v)

toPolygon

public static Geometry toPolygon(QuadEdge[] e)

nextIndex

public static int nextIndex(int index)
Finds the next index around the triangle. Index may be an edge or vertex index.

Parameters:
index -
Returns:

kill

public void kill()

isLive

public boolean isLive()

getEdges

public QuadEdge[] getEdges()

getEdge

public QuadEdge getEdge(int i)

getVertex

public Vertex getVertex(int i)

getVertices

public Vertex[] getVertices()
Gets the vertices for this triangle.

Returns:
a new array containing the triangle vertices

getCoordinate

public Coordinate getCoordinate(int i)

getEdgeIndex

public int getEdgeIndex(QuadEdge e)
Gets the index for the given edge of this triangle

Parameters:
e - a QuadEdge
Returns:
the index of the edge in this triangle

getEdgeIndex

public int getEdgeIndex(Vertex v)
Gets the index for the edge that starts at vertex v.

Parameters:
v - the vertex to find the edge for
Returns:
the index of the edge starting at the vertex

getEdgeSegment

public void getEdgeSegment(int i,
                           LineSegment seg)

getCoordinates

public Coordinate[] getCoordinates()

contains

public boolean contains(Coordinate pt)

getGeometry

public Geometry getGeometry(GeometryFactory fact)

toString

public java.lang.String toString()
Overrides:
toString in class java.lang.Object

isBorder

public boolean isBorder()
Tests whether this triangle is adjacent to the outside of the subdivision.

Returns:
true if the triangle is adjacent to the subdivision exterior

isBorder

public boolean isBorder(int i)

getAdjacentTriangleAcrossEdge

public QuadEdgeTriangle getAdjacentTriangleAcrossEdge(int edgeIndex)

getAdjacentTriangleEdgeIndex

public int getAdjacentTriangleEdgeIndex(int i)

getTrianglesAdjacentToVertex

public java.util.List getTrianglesAdjacentToVertex(int vertexIndex)

getNeighbours

public QuadEdgeTriangle[] getNeighbours()
Gets the neighbours of this triangle. If there is no neighbour triangle, the array element is null

Returns:
an array containing the 3 neighbours of this triangle