Class EdgeGraph

A graph comprised of HalfEdges. It supports tracking the vertices in the graph via edges incident on them, to allow efficient lookup of edges and vertices.

Inheritance

object

EdgeGraph

DissolveEdgeGraph

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Namespace: NetTopologySuite.EdgeGraph

Assembly: NetTopologySuite.dll

Syntax

public class EdgeGraph

Remarks

This class may be subclassed to use a different subclass of HalfEdge, by overriding CreateEdge(Coordinate). If additional logic is required to initialize edges then AddEdge(Coordinate, Coordinate) can be overridden as well.

Methods

AddEdge(Coordinate, Coordinate)

Adds an edge between the coordinates orig and dest to this graph.

Declaration

public virtual HalfEdge AddEdge(Coordinate orig, Coordinate dest)

Parameters

Type	Name	Description
Coordinate	orig	the edge origin location
Coordinate	dest	the edge destination location

Returns

Type	Description
HalfEdge	The created edge

Remarks

Only valid edges can be added (in particular, zero-length segments cannot be added)

See Also

IsValidEdge(Coordinate, Coordinate)

CreateEdge(Coordinate)

Creates a single HalfEdge. Override to use a different HalfEdge subclass.

Declaration

protected virtual HalfEdge CreateEdge(Coordinate orig)

Parameters

Type	Name	Description
Coordinate	orig	the origin location

Returns

Type	Description
HalfEdge	a new HalfEdge with the given origin

FindEdge(Coordinate, Coordinate)

Finds an edge in this graph with the given origin and destination, if one exists.

Declaration

public HalfEdge FindEdge(Coordinate orig, Coordinate dest)

Parameters

Type	Name	Description
Coordinate	orig	the origin location
Coordinate	dest	the destination location

Returns

Type	Description
HalfEdge	an edge with the given orig and dest, or null if none exists

GetVertexEdges()

Gets all HalfEdges in the graph. Both edges of edge pairs are included.

Declaration

public IEnumerable<HalfEdge> GetVertexEdges()

Returns

Type	Description
IEnumerable<HalfEdge>	An enumeration of the graph edges

IsValidEdge(Coordinate, Coordinate)

Test if an the coordinates for an edge form a valid edge (with non-zero length)

Declaration

public static bool IsValidEdge(Coordinate orig, Coordinate dest)

Parameters

Type	Name	Description
Coordinate	orig	The start coordinate
Coordinate	dest	The end coordinate

Returns

Type	Description
bool	true of the edge formed is valid