Package org.locationtech.jts.geomgraph

Class GeometryGraph

java.lang.Object

org.locationtech.jts.geomgraph.PlanarGraph

org.locationtech.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 org.locationtech.jts.geomgraph.PlanarGraph

edgeEndList, edges, nodes

Constructor Summary

Constructors

Constructor	Description
GeometryGraph(int argIndex, Geometry parentGeom)
GeometryGraph(int argIndex, Geometry parentGeom, BoundaryNodeRule boundaryNodeRule)

Method Summary

Modifier and Type	Method	Description
void	addEdge(Edge e)	Add an Edge computed externally.
void	addPoint(Coordinate 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.
SegmentIntersector	computeSelfNodes(LineIntersector li, boolean computeRingSelfNodes, boolean isDoneIfProperInt)	Compute self-nodes, taking advantage of the Geometry type to minimize the number of intersection tests.
void	computeSplitEdges(List edgelist)
static int	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	getBoundaryNodes()
Coordinate[]	getBoundaryPoints()
Geometry	getGeometry()
Coordinate	getInvalidPoint()
boolean	hasTooFewPoints()	This constructor is used by clients that wish to add Edges explicitly, rather than adding a Geometry.
int	locate(Coordinate pt)	Determines the Location of the given Coordinate in this geometry.

Methods inherited from class org.locationtech.jts.geomgraph.PlanarGraph

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

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 parentGeom)

GeometryGraph

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

Method Detail

determineBoundary

public static int 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)

hasTooFewPoints

public boolean hasTooFewPoints()

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

getInvalidPoint

public Coordinate getInvalidPoint()

getGeometry

public Geometry getGeometry()

getBoundaryNodeRule

public BoundaryNodeRule getBoundaryNodeRule()

getBoundaryNodes

public Collection getBoundaryNodes()

getBoundaryPoints

public Coordinate[] getBoundaryPoints()

findEdge

public Edge findEdge(LineString line)

computeSplitEdges

public void computeSplitEdges(List edgelist)

addEdge

public void addEdge(Edge e)

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

addPoint

public void addPoint(Coordinate pt)

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

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

Returns:

the computed SegmentIntersector containing information about the intersections found

computeSelfNodes

public SegmentIntersector computeSelfNodes(LineIntersector li,
                                           boolean computeRingSelfNodes,
                                           boolean isDoneIfProperInt)

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

isDoneIfProperInt - short-circuit the intersection computation if a proper intersection is found

Returns:

the computed SegmentIntersector containing information about the intersections found

computeEdgeIntersections

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

locate

public int locate(Coordinate pt)

Determines the Location of the given Coordinate in this geometry.

Parameters:

pt - the point to test

Returns:

the location of the point in the geometry