Class PlanarGraph

Represents a directed graph which is embeddable in a planar surface. This class and the other classes in this package serve as a framework for building planar graphs for specific algorithms. This class must be subclassed to expose appropriate methods to construct the graph. This allows controlling the types of graph components ({DirectedEdge}s, Edges and Nodes) which can be added to the graph. An application which uses the graph framework will almost always provide subclasses for one or more graph components, which hold application-specific data and graph algorithms.

Inheritance

object

PlanarGraph

LineMergeGraph

PolygonizeGraph

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Namespace: NetTopologySuite.Planargraph

Assembly: NetTopologySuite.dll

Syntax

public abstract class PlanarGraph

Fields

dirEdges

Declaration

protected IList<DirectedEdge> dirEdges

Field Value

Type	Description
IList<DirectedEdge>

nodeMap

Declaration

protected NodeMap nodeMap

Field Value

Type	Description
NodeMap

Properties

Edges

Returns the Edges that have been added to this PlanarGraph.

Declaration

public IList<Edge> Edges { get; protected set; }

Property Value

Type	Description
IList<Edge>

Nodes

Returns the Nodes in this PlanarGraph.

Declaration

public ICollection<Node> Nodes { get; }

Property Value

Type	Description
ICollection<Node>

Methods

Add(DirectedEdge)

Adds the Edge to this PlanarGraph; only subclasses can add DirectedEdges, to ensure the edges added are of the right class.

Declaration

protected void Add(DirectedEdge dirEdge)

Parameters

Type	Name	Description
DirectedEdge	dirEdge

Add(Edge)

Adds the Edge and its DirectedEdges with this PlanarGraph. Assumes that the Edge has already been created with its associated DirectEdges. Only subclasses can add Edges, to ensure the edges added are of the right class.

Declaration

protected void Add(Edge edge)

Parameters

Type	Name	Description
Edge	edge

Add(Node)

Adds a node to the map, replacing any that is already at that location. Only subclasses can add Nodes, to ensure Nodes are of the right type.

Declaration

protected void Add(Node node)

Parameters

Type	Name	Description
Node	node

FindNode(Coordinate)

Returns the Node at the given pt, or null if no Node was there.

Declaration

public Node FindNode(Coordinate pt)

Parameters

Type	Name	Description
Coordinate	pt	The location

Returns

Type	Description
Node	The node found or null if this graph contains no node at the location

FindNodesOfDegree(int)

Returns all Nodes with the given number of Edges around it.

Declaration

public IList<Node> FindNodesOfDegree(int degree)

Parameters

Type	Name	Description
int	degree

Returns

Type	Description
IList<Node>

GetDirEdgeEnumerator()

Returns an Iterator over the DirectedEdges in this PlanarGraph, in the order in which they were added.

Declaration

public IEnumerator<DirectedEdge> GetDirEdgeEnumerator()

Returns

Type	Description
IEnumerator<DirectedEdge>

GetEdgeEnumerator()

Returns an Iterator over the Edges in this PlanarGraph, in the order in which they were added.

Declaration

public IEnumerator<Edge> GetEdgeEnumerator()

Returns

Type	Description
IEnumerator<Edge>

GetNodeEnumerator()

Returns an IEnumerator over the Nodes in this PlanarGraph.

Declaration

public IEnumerator<Node> GetNodeEnumerator()

Returns

Type	Description
IEnumerator<Node>

Remove(DirectedEdge)

Removes a DirectedEdge from its from-Node and from this PlanarGraph.

Declaration

public void Remove(DirectedEdge de)

Parameters

Type	Name	Description
DirectedEdge	de

Remarks

This method does not remove the Nodes associated with the DirectedEdge, even if the removal of the DirectedEdge reduces the degree of a Node to zero.

Remove(Edge)

Removes an Edge and its associated DirectedEdges from their from-Nodes and from this PlanarGraph. Note: This method does not remove the Nodes associated with the Edge, even if the removal of the Edge reduces the degree of a Node to zero.

Declaration

public void Remove(Edge edge)

Parameters

Type	Name	Description
Edge	edge

Remove(Node)

Removes a node from the graph, along with any associated DirectedEdges and Edges.

Declaration

public void Remove(Node node)

Parameters

Type	Name	Description
Node	node