/**
* Copyright (C) 2007 - 2016 52°North Initiative for Geospatial Open Source
* Software GmbH
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*
* If the program is linked with libraries which are licensed under one of
* the following licenses, the combination of the program with the linked
* library is not considered a "derivative work" of the program:
*
* • Apache License, version 2.0
* • Apache Software License, version 1.0
* • GNU Lesser General Public License, version 3
* • Mozilla Public License, versions 1.0, 1.1 and 2.0
* • Common Development and Distribution License (CDDL), version 1.0
*
* Therefore the distribution of the program linked with libraries licensed
* under the aforementioned licenses, is permitted by the copyright holders
* if the distribution is compliant with both the GNU General Public
* License version 2 and the aforementioned licenses.
*
* As an exception to the terms of the GPL, you may copy, modify,
* propagate, and distribute a work formed by combining 52°North WPS
* GeoTools Modules with the Eclipse Libraries, or a work derivative of
* such a combination, even if such copying, modification, propagation, or
* distribution would otherwise violate the terms of the GPL. Nothing in
* this exception exempts you from complying with the GPL in all respects
* for all of the code used other than the Eclipse Libraries. You may
* include this exception and its grant of permissions when you distribute
* 52°North WPS GeoTools Modules. Inclusion of this notice with such a
* distribution constitutes a grant of such permissions. If you do not wish
* to grant these permissions, remove this paragraph from your
* distribution. "52°North WPS GeoTools Modules" means the 52°North WPS
* modules using GeoTools functionality - software licensed under version 2
* or any later version of the GPL, or a work based on such software and
* licensed under the GPL. "Eclipse Libraries" means Eclipse Modeling
* Framework Project and XML Schema Definition software distributed by the
* Eclipse Foundation and licensed under the Eclipse Public License Version
* 1.0 ("EPL"), or a work based on such software and licensed under the EPL.
*
* This program 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 General
* Public License for more details.
*/
package org.n52.wps.server.algorithm.simplify;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.geotools.feature.FeatureCollection;
import org.geotools.feature.FeatureIterator;
import org.geotools.feature.IllegalAttributeException;
import org.n52.wps.io.data.IData;
import org.n52.wps.io.data.binding.complex.GTVectorDataBinding;
import org.n52.wps.io.data.binding.literal.LiteralDoubleBinding;
import org.n52.wps.server.AbstractAlgorithm;
import org.n52.wps.server.AbstractSelfDescribingAlgorithm;
import org.opengis.feature.Feature;
import org.opengis.feature.simple.SimpleFeature;
import com.vividsolutions.jts.geom.Geometry;
import com.vividsolutions.jts.geom.LineString;
import com.vividsolutions.jts.geom.MultiLineString;
import com.vividsolutions.jts.geom.MultiPolygon;
import com.vividsolutions.jts.geom.Polygon;
import com.vividsolutions.jts.simplify.DouglasPeuckerSimplifier;
public class DouglasPeuckerAlgorithm extends AbstractSelfDescribingAlgorithm{
Logger LOGGER = LoggerFactory.getLogger(DouglasPeuckerAlgorithm.class);
private List<String> errors = new ArrayList<String>();
public Map<String, IData> run(Map<String, List<IData>> inputData) {
if(inputData==null || !inputData.containsKey("FEATURES")){
throw new RuntimeException("Error while allocating input parameters");
}
List<IData> dataList = inputData.get("FEATURES");
if(dataList == null || dataList.size() != 1){
throw new RuntimeException("Error while allocating input parameters");
}
IData firstInputData = dataList.get(0);
FeatureCollection featureCollection = ((GTVectorDataBinding) firstInputData).getPayload();
FeatureIterator iter = featureCollection.features();
if( !inputData.containsKey("TOLERANCE")){
throw new RuntimeException("Error while allocating input parameters");
}
List<IData> widthDataList = inputData.get("TOLERANCE");
if(widthDataList == null || widthDataList.size() != 1){
throw new RuntimeException("Error while allocating input parameters");
}
Double tolerance = ((LiteralDoubleBinding) widthDataList.get(0)).getPayload();
while(iter.hasNext()) {
SimpleFeature f = (SimpleFeature) iter.next();
if(f.getDefaultGeometry() == null) {
LOGGER.debug("defaultGeometry is null in feature id:" + f.getID());
throw new NullPointerException("defaultGeometry is null in feature id: " + f.getID());
}
Map<Object, Object> userData = f.getUserData();
try{
Geometry in = (Geometry) f.getDefaultGeometry();
Geometry out = DouglasPeuckerSimplifier.simplify(in, tolerance);
/*
* THIS PASSAGE WAS CONTRIBUTED BY GOBE HOBONA.
*The simplification of MultiPolygons produces Polygon geometries. This becomes inconsistent with the original schema (which was of MultiPolygons).
*To ensure that the output geometries match that of the original schema we add the Polygon(from the simplication) to a MultiPolygon object
*
*This is issue is known to affect MultiPolygon geometries only, other geometries need to be tested to ensure conformance with the original (input) schema
*/
if(in.getGeometryType().equals("MultiPolygon") && out.getGeometryType().equals("Polygon"))
{
MultiPolygon mp = (MultiPolygon)in;
Polygon[] p = {(Polygon)out};
mp = new MultiPolygon(p,mp.getFactory());
f.setDefaultGeometry(mp);
}
else if(in.getGeometryType().equals("MultiLineString") && out.getGeometryType().equals("LineString")) {
MultiLineString ml = (MultiLineString)in;
LineString[] l = {(LineString)out};
ml = new MultiLineString(l,ml.getFactory());
f.setDefaultGeometry(ml);
}
else {
f.setDefaultGeometry(out);
}
Geometry g = (Geometry) f.getDefaultGeometry();
g.setUserData(userData);
}
catch(IllegalAttributeException e) {
throw new RuntimeException("geometrytype of result is not matching", e);
}
}
HashMap<String, IData> result = new HashMap<String, IData>();
result.put("SIMPLIFIED_FEATURES", new GTVectorDataBinding(featureCollection));
return result;
}
public List<String> getErrors() {
return errors;
}
public Class getInputDataType(String id) {
if(id.equalsIgnoreCase("FEATURES")){
return GTVectorDataBinding.class;
}else if(id.equalsIgnoreCase("TOLERANCE")){
return LiteralDoubleBinding.class;
}
return null;
}
public Class getOutputDataType(String id) {
if(id.equalsIgnoreCase("SIMPLIFIED_FEATURES")){
return GTVectorDataBinding.class;
}
return null;
}
@Override
public List<String> getInputIdentifiers() {
List<String> identifierList = new ArrayList<String>();
identifierList.add("FEATURES");
identifierList.add("TOLERANCE");
return identifierList;
}
@Override
public List<String> getOutputIdentifiers() {
List<String> identifierList = new ArrayList<String>();
identifierList.add("SIMPLIFIED_FEATURES");
return identifierList;
}
}