com.revolsys.jts.geomgraph

Class GeometryGraph

java.lang.Object

com.revolsys.jts.geomgraph.PlanarGraph

com.revolsys.jts.geomgraph.GeometryGraph

public class GeometryGraph
extends PlanarGraph

A GeometryGraph is a graph that models a given Geometry

Version:

1.7

Field Summary

Fields inherited from class com.revolsys.jts.geomgraph.PlanarGraph

edgeEndList, edges

Constructor Summary

Constructors

Constructor and Description
GeometryGraph(int argIndex, Geometry geometry)
GeometryGraph(int argIndex, Geometry geometry, BoundaryNodeRule boundaryNodeRule)

Method Summary

Methods

Modifier and Type	Method and Description
void	addEdge(Edge edge) Add an Edge computed externally.
void	addPoint(Point pt) Add a point computed externally.
SegmentIntersector	computeEdgeIntersections(GeometryGraph g, LineIntersector li, boolean includeProper)
SegmentIntersector	computeSelfNodes(LineIntersector li, boolean computeRingSelfNodes) Compute self-nodes, taking advantage of the Geometry type to minimize the number of intersection tests.
void	computeSplitEdges(List<Edge> edgelist)
static Location	determineBoundary(BoundaryNodeRule boundaryNodeRule, int boundaryCount) This method implements the Boundary Determination Rule for determining whether a component (node or edge) that appears multiple times in elements of a MultiGeometry is in the boundary or the interior of the Geometry The SFS uses the "Mod-2 Rule", which this function implements An alternative (and possibly more intuitive) rule would be the "At Most One Rule": isInBoundary = (componentCount == 1)
Edge	findEdge(LineString line)
BoundaryNodeRule	getBoundaryNodeRule()
Collection<Node>	getBoundaryNodes()
Point[]	getBoundaryPoints()
Geometry	getGeometry()
Point	getInvalidPoint()
boolean	hasTooFewPoints() This constructor is used by clients that wish to add Edges explicitly, rather than adding a Geometry.
Location	locate(Point pt) Determines the Location of the given Coordinates in this geometry.

Methods inherited from class com.revolsys.jts.geomgraph.PlanarGraph

add, addEdges, addNode, addNode, edges, find, findEdge, findEdgeEnd, findEdgeInSameDirection, getEdgeEnds, getEdgeIterator, getNodeIterator, getNodeMap, getNodes, insertEdge, isBoundaryNode, linkAllDirectedEdges, linkResultDirectedEdges, linkResultDirectedEdges

Methods inherited from class java.lang.Object

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

Constructor Detail

GeometryGraph

public GeometryGraph(int argIndex,
             Geometry geometry)

GeometryGraph

public GeometryGraph(int argIndex,
             Geometry geometry,
             BoundaryNodeRule boundaryNodeRule)

Method Detail

determineBoundary

public static Location determineBoundary(BoundaryNodeRule boundaryNodeRule,
                         int boundaryCount)

This method implements the Boundary Determination Rule for determining whether a component (node or edge) that appears multiple times in elements of a MultiGeometry is in the boundary or the interior of the Geometry
The SFS uses the "Mod-2 Rule", which this function implements
An alternative (and possibly more intuitive) rule would be the "At Most One Rule": isInBoundary = (componentCount == 1)

addEdge

public void addEdge(Edge edge)

Add an Edge computed externally. The label on the Edge is assumed to be correct.

addPoint

public void addPoint(Point pt)

Add a point computed externally. The point is assumed to be a Point Geometry part, which has a location of INTERIOR.

computeEdgeIntersections

public SegmentIntersector computeEdgeIntersections(GeometryGraph g,
                                          LineIntersector li,
                                          boolean includeProper)

computeSelfNodes

public SegmentIntersector computeSelfNodes(LineIntersector li,
                                  boolean computeRingSelfNodes)

Compute self-nodes, taking advantage of the Geometry type to minimize the number of intersection tests. (E.g. rings are not tested for self-intersection, since they are assumed to be valid).

Parameters:

li - the LineIntersector to use

computeRingSelfNodes - if , intersection checks are optimized to not test rings for self-intersection

Returns:

the SegmentIntersector used, containing information about the intersections found

computeSplitEdges

public void computeSplitEdges(List<Edge> edgelist)

findEdge

public Edge findEdge(LineString line)

getBoundaryNodeRule

public BoundaryNodeRule getBoundaryNodeRule()

getBoundaryNodes

public Collection<Node> getBoundaryNodes()

getBoundaryPoints

public Point[] getBoundaryPoints()

getGeometry

public Geometry getGeometry()

getInvalidPoint

public Point getInvalidPoint()

hasTooFewPoints

public boolean hasTooFewPoints()

This constructor is used by clients that wish to add Edges explicitly, rather than adding a Geometry. (An example is Buffer).

locate

public Location locate(Point pt)

Determines the Location of the given Coordinates in this geometry.

Parameters:

p - the point to test

Returns:

the location of the point in the geometry