com.vividsolutions.jts.operation.overlay.MaximalEdgeRing Maven / Gradle / Ivy
/*
* The JTS Topology Suite is a collection of Java classes that
* implement the fundamental operations required to validate a given
* geo-spatial data set to a known topological specification.
*
* Copyright (C) 2001 Vivid Solutions
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* For more information, contact:
*
* Vivid Solutions
* Suite #1A
* 2328 Government Street
* Victoria BC V8T 5G5
* Canada
*
* (250)385-6040
* www.vividsolutions.com
*/
package com.vividsolutions.jts.operation.overlay;
import java.util.*;
import com.vividsolutions.jts.geom.*;
import com.vividsolutions.jts.algorithm.*;
import com.vividsolutions.jts.geomgraph.*;
/**
* A ring of {@link DirectedEdge}s which may contain nodes of degree > 2.
* A MaximalEdgeRing may represent two different spatial entities:
*
* - a single polygon possibly containing inversions (if the ring is oriented CW)
*
- a single hole possibly containing exversions (if the ring is oriented CCW)
*
* If the MaximalEdgeRing represents a polygon,
* the interior of the polygon is strongly connected.
*
* These are the form of rings used to define polygons under some spatial data models.
* However, under the OGC SFS model, {@link MinimalEdgeRing}s are required.
* A MaximalEdgeRing can be converted to a list of MinimalEdgeRings using the
* {@link #buildMinimalRings() } method.
*
* @version 1.7
* @see com.vividsolutions.jts.operation.overlay.MinimalEdgeRing
*/
public class MaximalEdgeRing
extends EdgeRing
{
public MaximalEdgeRing(DirectedEdge start, GeometryFactory geometryFactory) {
super(start, geometryFactory);
}
public DirectedEdge getNext(DirectedEdge de)
{
return de.getNext();
}
public void setEdgeRing(DirectedEdge de, EdgeRing er)
{
de.setEdgeRing(er);
}
/**
* For all nodes in this EdgeRing,
* link the DirectedEdges at the node to form minimalEdgeRings
*/
public void linkDirectedEdgesForMinimalEdgeRings()
{
DirectedEdge de = startDe;
do {
Node node = de.getNode();
((DirectedEdgeStar) node.getEdges()).linkMinimalDirectedEdges(this);
de = de.getNext();
} while (de != startDe);
}
public List buildMinimalRings()
{
List minEdgeRings = new ArrayList();
DirectedEdge de = startDe;
do {
if (de.getMinEdgeRing() == null) {
EdgeRing minEr = new MinimalEdgeRing(de, geometryFactory);
minEdgeRings.add(minEr);
}
de = de.getNext();
} while (de != startDe);
return minEdgeRings;
}
}