com.vividsolutions.jts.geomgraph

Class DirectedEdgeStar

java.lang.Object

com.vividsolutions.jts.geomgraph.EdgeEndStar

com.vividsolutions.jts.geomgraph.DirectedEdgeStar

public class DirectedEdgeStar
extends EdgeEndStar

A DirectedEdgeStar is an ordered list of outgoing DirectedEdges around a node. It supports labelling the edges as well as linking the edges to form both MaximalEdgeRings and MinimalEdgeRings.

Version:

1.7

Field Summary

Fields inherited from class com.vividsolutions.jts.geomgraph.EdgeEndStar

edgeList, edgeMap

Constructor Summary

Constructors

Constructor and Description
DirectedEdgeStar()

Method Summary

Methods

Modifier and Type	Method and Description
void	computeDepths(DirectedEdge de)
void	computeLabelling(GeometryGraph[] geom) Compute the labelling for all dirEdges in this star, as well as the overall labelling
void	findCoveredLineEdges() Traverse the star of edges, maintaing the current location in the result area at this node (if any).
Label	getLabel()
int	getOutgoingDegree()
int	getOutgoingDegree(EdgeRing er)
DirectedEdge	getRightmostEdge()
void	insert(EdgeEnd ee) Insert a directed edge in the list
void	linkAllDirectedEdges()
void	linkMinimalDirectedEdges(EdgeRing er)
void	linkResultDirectedEdges() Traverse the star of DirectedEdges, linking the included edges together.
void	mergeSymLabels() For each dirEdge in the star, merge the label from the sym dirEdge into the label
void	print(PrintStream out)
void	updateLabelling(Label nodeLabel) Update incomplete dirEdge labels from the labelling for the node

Methods inherited from class com.vividsolutions.jts.geomgraph.EdgeEndStar

findIndex, getCoordinate, getDegree, getEdges, getNextCW, insertEdgeEnd, isAreaLabelsConsistent, iterator, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

DirectedEdgeStar

public DirectedEdgeStar()

Method Detail

insert

public void insert(EdgeEnd ee)

Insert a directed edge in the list

Specified by:

insert in class EdgeEndStar

getLabel

public Label getLabel()

getOutgoingDegree

public int getOutgoingDegree()

getOutgoingDegree

public int getOutgoingDegree(EdgeRing er)

getRightmostEdge

public DirectedEdge getRightmostEdge()

computeLabelling

public void computeLabelling(GeometryGraph[] geom)

Compute the labelling for all dirEdges in this star, as well as the overall labelling

Overrides:

computeLabelling in class EdgeEndStar

mergeSymLabels

public void mergeSymLabels()

For each dirEdge in the star, merge the label from the sym dirEdge into the label

updateLabelling

public void updateLabelling(Label nodeLabel)

Update incomplete dirEdge labels from the labelling for the node

linkResultDirectedEdges

public void linkResultDirectedEdges()

Traverse the star of DirectedEdges, linking the included edges together. To link two dirEdges, the pointer for an incoming dirEdge is set to the next outgoing edge.

DirEdges are only linked if:

• they belong to an area (i.e. they have sides)
• they are marked as being in the result

Edges are linked in CCW order (the order they are stored). This means that rings have their face on the Right (in other words, the topological location of the face is given by the RHS label of the DirectedEdge)

PRECONDITION: No pair of dirEdges are both marked as being in the result

linkMinimalDirectedEdges

public void linkMinimalDirectedEdges(EdgeRing er)

linkAllDirectedEdges

public void linkAllDirectedEdges()

findCoveredLineEdges

public void findCoveredLineEdges()

Traverse the star of edges, maintaing the current location in the result area at this node (if any). If any L edges are found in the interior of the result, mark them as covered.

computeDepths

public void computeDepths(DirectedEdge de)

print

public void print(PrintStream out)

Overrides:

print in class EdgeEndStar