svn-gvsig-desktop / trunk / org.gvsig.desktop / org.gvsig.desktop.plugin / org.gvsig.editing.app / org.gvsig.editing.app.mainplugin / src / main / java / org / gvsig / editing / gui / cad / tools / split / SplitStrategy.java @ 40557
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/**
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* gvSIG. Desktop Geographic Information System.
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*
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* Copyright (C) 2007-2013 gvSIG Association.
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*
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* This program is free software; you can redistribute it and/or
|
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* modify it under the terms of the GNU General Public License
|
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* as published by the Free Software Foundation; either version 3
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* of the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
|
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
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* GNU General Public License for more details.
|
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*
|
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* You should have received a copy of the GNU General Public License
|
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* along with this program; if not, write to the Free Software
|
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
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* MA 02110-1301, USA.
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*
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* For any additional information, do not hesitate to contact us
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* at info AT gvsig.com, or visit our website www.gvsig.com.
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*/
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|
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/* Spatial Operations & Editing Tools for uDig
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*
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* Axios Engineering under a funding contract with:
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* Diputaci?n Foral de Gipuzkoa, Ordenaci?n Territorial
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*
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* http://b5m.gipuzkoa.net
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* http://www.axios.es
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*
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* (C) 2006, Diputaci?n Foral de Gipuzkoa, Ordenaci?n Territorial (DFG-OT).
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* DFG-OT agrees to licence under Lesser General Public License (LGPL).
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*
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* You can redistribute it and/or modify it under the terms of the
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* GNU Lesser General Public License as published by the Free Software
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* Foundation; version 2.1 of the License.
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*
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* This library is distributed in the hope that it will be useful,
|
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
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* Lesser General Public License for more details.
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*/
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/*
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* Created on 10-abr-2006
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*
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* gvSIG. Sistema de Informaci?n Geogr?fica de la Generalitat Valenciana
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*
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* Copyright (C) 2004 IVER T.I. and Generalitat Valenciana.
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*
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* This program is free software; you can redistribute it and/or
|
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* modify it under the terms of the GNU General Public License
|
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* as published by the Free Software Foundation; either version 2
|
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* of the License, or (at your option) any later version.
|
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*
|
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* This program is distributed in the hope that it will be useful,
|
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
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* GNU General Public License for more details.
|
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*
|
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* You should have received a copy of the GNU General Public License
|
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* along with this program; if not, write to the Free Software
|
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* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,USA.
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*
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* For more information, contact:
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*
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* Generalitat Valenciana
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* Conselleria d'Infraestructures i Transport
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* Av. Blasco Ib??ez, 50
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* 46010 VALENCIA
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* SPAIN
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*
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* +34 963862235
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* gvsig@gva.es
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* www.gvsig.gva.es
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*
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* or
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*
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* IVER T.I. S.A
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* Salamanca 50
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* 46005 Valencia
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* Spain
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*
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* +34 963163400
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* dac@iver.es
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*/
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/* CVS MESSAGES:
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*
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* $Id:
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* $Log:
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*/
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package org.gvsig.editing.gui.cad.tools.split; |
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import java.util.ArrayList; |
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import java.util.Collections; |
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import java.util.HashMap; |
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import java.util.Iterator; |
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import java.util.List; |
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import java.util.Map; |
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import com.vividsolutions.jts.algorithm.CGAlgorithms; |
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import com.vividsolutions.jts.geom.Coordinate; |
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import com.vividsolutions.jts.geom.CoordinateArrays; |
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import com.vividsolutions.jts.geom.Geometry; |
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import com.vividsolutions.jts.geom.GeometryCollection; |
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import com.vividsolutions.jts.geom.GeometryFactory; |
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import com.vividsolutions.jts.geom.LineString; |
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import com.vividsolutions.jts.geom.LinearRing; |
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import com.vividsolutions.jts.geom.Location; |
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import com.vividsolutions.jts.geom.MultiLineString; |
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import com.vividsolutions.jts.geom.MultiPolygon; |
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import com.vividsolutions.jts.geom.Polygon; |
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import com.vividsolutions.jts.geomgraph.DirectedEdge; |
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import com.vividsolutions.jts.geomgraph.Node; |
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/**
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* This class is based in the AXIOS team work for UDIG project.
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*
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* We have adapted it slightly for the gvsig project
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* (exchange the I18 system, etc)
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*
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* @author Alvaro Zabala
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*
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*/
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/*
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* Performs a split of a LineString, MultiLineString, Polygon or MultiPolygon using a provided
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* LineString as cutting edge.
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*
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* @author Gabriel Rold?n, Axios Engineering
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* @author Mauricio Pazos, Axios Engineering
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* @since 1.1.0
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*/
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public class SplitStrategy { |
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private final LineString splittingLine; |
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private static final Map /* <Class, Class<? extends SpecificSplitOp> */strategies; |
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static {
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Map knownStrategies = new HashMap(); |
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knownStrategies.put(LineString.class, LineStringSplitter.class); |
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knownStrategies.put(MultiLineString.class, MultiLineStringSplitter.class); |
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knownStrategies.put(Polygon.class, PolygonSplitter.class);
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knownStrategies.put(MultiPolygon.class, MultiPolygonSplitter.class); |
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strategies = Collections.unmodifiableMap(knownStrategies);
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} |
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public SplitStrategy( final LineString splittingLine ) { |
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if (splittingLine == null) { |
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throw new NullPointerException(); |
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} |
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this.splittingLine = splittingLine;
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} |
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public static Geometry splitOp( Geometry geom, LineString splitLine ) { |
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SplitStrategy op = new SplitStrategy(splitLine);
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Geometry splittedGeometries = op.split(geom); |
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return splittedGeometries;
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} |
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/**
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* @param splitee
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* @return a <code>Geometry</code> containing all the splitted parts as aggregates. Use
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* {@link Geometry#getGeometryN(int) getGeometryN(int)} to get each part.
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* @throws NullPointerException if geom is null
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* @throws IllegalArgumentException if geom is not of an acceptable geometry type to be splitted
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* (i.e. not a linestring, multilinestring, polygon or multipolygon)
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*/
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public Geometry split( final Geometry splitee ) { |
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if (splitee == null) { |
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throw new NullPointerException(); |
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} |
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Class spliteeClass = splitee.getClass();
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SpecificSplitOp splitOp = findSplitOp(spliteeClass); |
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Geometry splitResult; |
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splitOp.setSplitter(splittingLine); |
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splitResult = splitOp.split(splitee); |
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return splitResult;
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} |
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private SpecificSplitOp findSplitOp( Class spliteeClass ) { |
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if (!strategies.containsKey(spliteeClass)) {
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throw new IllegalArgumentException("La geometria especificada no soporta la operacion 'split'"); |
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} |
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final Class splitOpClass = (Class) strategies.get(spliteeClass); |
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SpecificSplitOp splitOp; |
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try {
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splitOp = (SpecificSplitOp) splitOpClass.newInstance(); |
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} catch (InstantiationException e) { |
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throw new RuntimeException("Cannot instantiate " + splitOpClass.getName(), e); |
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} catch (IllegalAccessException e) { |
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throw (RuntimeException) new RuntimeException("Illegal access exception for " |
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+ splitOpClass.getName()).initCause(e); |
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} |
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return splitOp;
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} |
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/**
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* @author Gabriel Rold?n, Axios Engineering
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* @author Mauricio Pazos, Axios Engineering
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* @since 1.1.0
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*/
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private static interface SpecificSplitOp { |
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public void setSplitter( LineString splitter ); |
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public Geometry split( Geometry splitee );
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} |
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/**
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* @author Gabriel Rold?n, Axios Engineering
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* @author Mauricio Pazos, Axios Engineering
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* @since 1.1.0
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*/
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private static abstract class AbstractSplitter implements SpecificSplitOp { |
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protected LineString splitter;
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public void setSplitter( LineString splitter ) { |
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this.splitter = splitter;
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} |
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} |
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/**
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* @author Gabriel Rold?n, Axios Engineering
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* @author Mauricio Pazos, Axios Engineering
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* @since 1.1.0
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*/
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private static class LineStringSplitter extends AbstractSplitter { |
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/**
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* No-op default constructor required to reflectively instantiate the class
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*/
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public LineStringSplitter() {
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// no-op
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} |
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/**
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* @param splitee the {@link LineString} to be splitted
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*/
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public Geometry split( Geometry splitee ) {
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Geometry splitted = ((LineString) splitee).difference(splitter); |
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return splitted;
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} |
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} |
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/**
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* @author Gabriel Rold?n, Axios Engineering
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* @author Mauricio Pazos, Axios Engineering
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* @since 1.1.0
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*/
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private static abstract class AbstractGeometryCollectionSplitter implements SpecificSplitOp { |
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private SpecificSplitOp singlePartSplitter;
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private AbstractGeometryCollectionSplitter( SpecificSplitOp singlePartSplitter ) {
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this.singlePartSplitter = singlePartSplitter;
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} |
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public final void setSplitter( LineString splitter ) { |
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singlePartSplitter.setSplitter(splitter); |
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} |
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public final Geometry split( final Geometry splitee ) { |
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final GeometryCollection coll = (GeometryCollection) splitee;
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final int numParts = coll.getNumGeometries(); |
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List splittedParts = new ArrayList(); |
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for( int partN = 0; partN < numParts; partN++ ) { |
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Geometry simplePartN = coll.getGeometryN(partN); |
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Geometry splittedPart = singlePartSplitter.split(simplePartN); |
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final int splittedPartsCount = splittedPart.getNumGeometries(); |
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for( int splittedPartN = 0; splittedPartN < splittedPartsCount; splittedPartN++ ) { |
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Geometry simpleSplittedPart = splittedPart.getGeometryN(splittedPartN); |
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splittedParts.add(simpleSplittedPart); |
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} |
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} |
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GeometryFactory gf = splitee.getFactory(); |
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GeometryCollection splittedCollection = buildFromParts(gf, splittedParts); |
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return splittedCollection;
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} |
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protected abstract GeometryCollection buildFromParts( GeometryFactory gf, List parts ); |
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} |
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/**
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* @author Gabriel Rold?n, Axios Engineering
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* @author Mauricio Pazos, Axios Engineering
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* @since 1.1.0
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*/
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private static class MultiLineStringSplitter extends AbstractGeometryCollectionSplitter { |
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public MultiLineStringSplitter() {
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super(new LineStringSplitter()); |
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} |
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@Override
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protected GeometryCollection buildFromParts( GeometryFactory gf, List parts ) { |
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LineString[] lines = (LineString[]) parts.toArray(new LineString[parts.size()]); |
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MultiLineString result = gf.createMultiLineString(lines); |
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return result;
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} |
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} |
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/**
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* @author Gabriel Rold?n, Axios Engineering
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* @author Mauricio Pazos, Axios Engineering
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* @since 1.1.0
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*/
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private static class MultiPolygonSplitter extends AbstractGeometryCollectionSplitter { |
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public MultiPolygonSplitter() {
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super(new PolygonSplitter()); |
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} |
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@Override
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protected GeometryCollection buildFromParts( GeometryFactory gf, List parts ) { |
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Polygon[] polygons = (Polygon[]) parts.toArray(new Polygon[parts.size()]); |
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MultiPolygon result = gf.createMultiPolygon(polygons); |
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return result;
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} |
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} |
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/**
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* Estrategia:
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* <ul>
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* <li> Construir un grafo con todos los edges y nodes de la intersecci?n del pol?gono con la
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* l?nea
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* <li> Ponderar los nodos seg?n la cantidad de edges incidentes. Nodos son solo las
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* intersecciones del boundary del poligono con el linestring y el punto inicial de cada parte
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* del boundary.
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* <li> Ponderar los edges seg?n son shared (todos los del linestring) o non shared (todos los
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* del boundary del poligono). Almacenar la lista de coordenadas del edge en el edge.
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* <li> Comenzar a recorrer el grafo por un nodo cualquiera, empezando por su primer edge
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* <li> Recorrer siempre hacia el nodo siguiente, seleccionando el edge cuyo primer segmento de
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* su linestring presenta un menor angulo a la izquiera (CCW) con el ultimo segmento del
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* linestring del edge en curso.
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* <li> Eliminar del grafo los edges non-shared que se utilizaron
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* <li> Disminuir en 1 la ponderaci?n de los nodos que se utilizaron
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* <li> Marcar los edges restantes que tengan algun nodo con ponderaci?n < 3 como non-shared
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* <li> Eliminar del grafo los nodos con ponderaci?n 1
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* </ul>
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*
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* @author Gabriel Rold?n, Axios Engineering
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* @author Mauricio Pazos, Axios Engineering
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* @since 1.1.0
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*/
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private static class PolygonSplitter extends AbstractSplitter { |
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/**
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* No-op default constructor required to reflectively instantiate the class
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*/
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public PolygonSplitter() {
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// no-op
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} |
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/**
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*
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*/
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public Geometry split( Geometry splitee ) {
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assert splitee instanceof Polygon;; |
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final Polygon polygon = (Polygon) splitee; |
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final Geometry splitted = splitPolygon(polygon);
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return splitted;
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} |
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/**
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*
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*/
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private Geometry splitPolygon( final Polygon geom ) { |
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SplitGraph graph = new SplitGraph(geom, splitter);
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final GeometryFactory gf = geom.getFactory();
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// sotore unsplitted holes for later addition
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List<LinearRing> unsplittedHoles = findUnsplittedHoles(graph, gf);
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List<List<SplitEdge>> allRings = findRings(graph); |
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List<Polygon> resultingPolygons = buildSimplePolygons(allRings, unsplittedHoles, gf); |
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Geometry result; |
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if (resultingPolygons.size() == 1) { |
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result = resultingPolygons.get(0);
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} else {
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Polygon[] array = resultingPolygons.toArray(new Polygon[resultingPolygons.size()]); |
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result = gf.createMultiPolygon(array); |
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} |
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return result;
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} |
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/**
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* Finds out and removes from the graph the edges that were originally holes in the polygon
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* and were not splitted by the splitting line.
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*
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* @param graph
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* @param gf
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* @return
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*/
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@SuppressWarnings("unchecked") |
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private List<LinearRing> findUnsplittedHoles( SplitGraph graph, GeometryFactory gf ) { |
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final List<LinearRing> unsplittedHoles = new ArrayList<LinearRing>(2); |
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final List<SplitEdge> edges = new ArrayList<SplitEdge>(); |
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for( Iterator it = graph.getEdgeIterator(); it.hasNext(); ) { |
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SplitEdge edge = (SplitEdge) it.next(); |
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edges.add(edge); |
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} |
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for( Iterator it = edges.iterator(); it.hasNext(); ) { |
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SplitEdge edge = (SplitEdge) it.next(); |
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if (edge.isHoleEdge()) {
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Coordinate[] coordinates = edge.getCoordinates();
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Coordinate start = coordinates[0];
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Coordinate end = coordinates[coordinates.length - 1];
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boolean isLinearRing = start.equals2D(end);
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if (isLinearRing) {
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graph.remove(edge); |
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LinearRing ring = gf.createLinearRing(coordinates); |
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unsplittedHoles.add(ring); |
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} |
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} |
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} |
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return unsplittedHoles;
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} |
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private List<Polygon> buildSimplePolygons( List<List<SplitEdge>> allRings, |
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List<LinearRing> unsplittedHoles,
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GeometryFactory gf ) { |
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List<Polygon> polygons = new ArrayList<Polygon>(allRings.size()); |
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for( List<SplitEdge> edgeList : allRings ) { |
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Polygon poly = buildPolygon(edgeList, gf);
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List<LinearRing> thisPolyHoles = new ArrayList<LinearRing>(unsplittedHoles.size()); |
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for( LinearRing holeRing : unsplittedHoles ) {
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if (poly.covers(holeRing)) {
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thisPolyHoles.add(holeRing); |
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} |
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} |
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unsplittedHoles.removeAll(thisPolyHoles); |
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int numHoles = thisPolyHoles.size();
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if (numHoles > 0) { |
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LinearRing[] holes = thisPolyHoles.toArray(new LinearRing[numHoles]); |
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LinearRing shell = gf.createLinearRing(poly.getExteriorRing().getCoordinates()); |
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poly = gf.createPolygon(shell, holes); |
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} |
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polygons.add(poly); |
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} |
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return polygons;
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} |
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private Polygon buildPolygon( List<SplitEdge> edgeList, GeometryFactory gf ) { |
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List<Coordinate> coords = new ArrayList<Coordinate>(); |
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Coordinate[] lastCoordinates = null; |
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for( SplitEdge edge : edgeList ) {
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Coordinate[] coordinates = edge.getCoordinates();
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if (lastCoordinates != null) { |
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Coordinate endPoint = lastCoordinates[lastCoordinates.length - 1];
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Coordinate startPoint = coordinates[0];
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if (!endPoint.equals2D(startPoint)) {
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coordinates = CoordinateArrays.copyDeep(coordinates); |
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CoordinateArrays.reverse(coordinates); |
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} |
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} |
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lastCoordinates = coordinates; |
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for( int i = 0; i < coordinates.length; i++ ) { |
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Coordinate coord = coordinates[i]; |
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coords.add(coord); |
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} |
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} |
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Coordinate[] shellCoords = new Coordinate[coords.size()]; |
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coords.toArray(shellCoords); |
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shellCoords = CoordinateArrays.removeRepeatedPoints(shellCoords); |
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LinearRing shell = gf.createLinearRing(shellCoords); |
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Polygon poly = gf.createPolygon(shell, (LinearRing[]) null); |
497 |
return poly;
|
498 |
} |
499 |
|
500 |
/**
|
501 |
* Builds a list of rings from the graph's edges
|
502 |
*
|
503 |
* @param graph
|
504 |
* @return
|
505 |
*/
|
506 |
@SuppressWarnings("unchecked") |
507 |
private List<List<SplitEdge>> findRings( SplitGraph graph ) { |
508 |
final List<List<SplitEdge>> rings = new ArrayList<List<SplitEdge>>(); |
509 |
|
510 |
DirectedEdge startEdge; |
511 |
// build each ring starting with the first edge belonging to the
|
512 |
// shell found
|
513 |
while( (startEdge = findShellEdge(graph)) != null ) { |
514 |
List<SplitEdge> ring = buildRing(graph, startEdge);
|
515 |
rings.add(ring); |
516 |
} |
517 |
return rings;
|
518 |
} |
519 |
|
520 |
private List<SplitEdge> buildRing( final SplitGraph graph, final DirectedEdge startEdge ) { |
521 |
// System.out.println("building ring edge list...");
|
522 |
final List<SplitEdge> ring = new ArrayList<SplitEdge>(); |
523 |
|
524 |
// follow this tessellation direction while possible,
|
525 |
// switch to the opposite when not, and continue with
|
526 |
// the same direction while possible.
|
527 |
// Start travelling clockwise, as we start with a shell edge,
|
528 |
// which is in clockwise order
|
529 |
final int direction = CGAlgorithms.COUNTERCLOCKWISE; |
530 |
|
531 |
DirectedEdge currentDirectedEdge = startEdge; |
532 |
DirectedEdge nextDirectedEdge = null;
|
533 |
|
534 |
while( nextDirectedEdge != startEdge ) {
|
535 |
SplitEdge edge = (SplitEdge) currentDirectedEdge.getEdge(); |
536 |
// System.out.println("adding " + edge);
|
537 |
if (ring.contains(edge)) {
|
538 |
throw new IllegalStateException("trying to add edge twice: " + edge); |
539 |
} |
540 |
ring.add(edge); |
541 |
|
542 |
DirectedEdge sym = currentDirectedEdge.getSym(); |
543 |
SplitGraphNode endNode = (SplitGraphNode) sym.getNode(); |
544 |
SplitEdgeStar nodeEdges = (SplitEdgeStar) endNode.getEdges(); |
545 |
nextDirectedEdge = nodeEdges.findClosestEdgeInDirection(sym, direction); |
546 |
|
547 |
assert nextDirectedEdge != null; |
548 |
|
549 |
currentDirectedEdge = nextDirectedEdge; |
550 |
} |
551 |
|
552 |
removeUnneededEdges(graph, ring); |
553 |
return ring;
|
554 |
} |
555 |
|
556 |
/**
|
557 |
* Removes from <code>graph</code> the edges in <code>ring</code> that are no more
|
558 |
* needed
|
559 |
*
|
560 |
* @param graph
|
561 |
* @param ring
|
562 |
*/
|
563 |
private void removeUnneededEdges( final SplitGraph graph, final List<SplitEdge> ring ) { |
564 |
for( SplitEdge edge : ring ) {
|
565 |
if (!edge.isInteriorEdge()) {
|
566 |
graph.remove(edge); |
567 |
} |
568 |
} |
569 |
|
570 |
for( SplitEdge edge : ring ) {
|
571 |
if (edge.isInteriorEdge()) {
|
572 |
Node node = graph.find(edge.getCoordinate()); |
573 |
int degree = node.getEdges().getDegree();
|
574 |
if (degree < 2) { |
575 |
graph.remove(edge); |
576 |
} |
577 |
} |
578 |
} |
579 |
} |
580 |
|
581 |
/**
|
582 |
* Returns the first edge found that belongs to the shell (not an interior edge, not one of
|
583 |
* a hole boundary)
|
584 |
* <p>
|
585 |
* This method relies on shell edges being labeled {@link Location#EXTERIOR exterior} to the
|
586 |
* left and {@link Location#INTERIOR interior} to the right.
|
587 |
* </p>
|
588 |
*
|
589 |
* @param graph
|
590 |
* @return the first shell edge found, or <code>null</code> if there are no more shell
|
591 |
* edges in <code>graph</code>
|
592 |
*/
|
593 |
private DirectedEdge findShellEdge( SplitGraph graph ) {
|
594 |
Iterator it = graph.getEdgeEnds().iterator();
|
595 |
DirectedEdge firstShellEdge = null;
|
596 |
while( it.hasNext() ) {
|
597 |
DirectedEdge de = (DirectedEdge) it.next(); |
598 |
SplitEdge edge = (SplitEdge) de.getEdge(); |
599 |
if (edge.isShellEdge()) {
|
600 |
firstShellEdge = de; |
601 |
break;
|
602 |
} |
603 |
} |
604 |
return firstShellEdge;
|
605 |
} |
606 |
} |
607 |
} |