Application: gvSIG desktop » gvSIG geoprocess

/*

 * gvSIG. Sistema de Informaci?n Geogr?fica de la Generalitat Valenciana

 *

 * Copyright (C) 2010 Generalitat Valenciana.

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version 2

 * of the License, or (at your option) any later version.

 *

 * 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.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,USA.

 *

 */

package org.gvsig.sextante.app.algorithm.buffer;

import java.util.ArrayList;

import java.util.Stack;

import com.vividsolutions.jts.geom.Geometry;

import com.vividsolutions.jts.geom.GeometryCollection;

import com.vividsolutions.jts.geom.GeometryFactory;

import com.vividsolutions.jts.geom.MultiPolygon;

import com.vividsolutions.jts.geom.Polygon;

import com.vividsolutions.jts.operation.buffer.BufferOp;

import com.vividsolutions.jts.operation.buffer.BufferParameters;

import com.vividsolutions.jts.simplify.TopologyPreservingSimplifier;

import es.unex.sextante.core.Sextante;

import es.unex.sextante.dataObjects.IVectorLayer;

import org.gvsig.fmap.dal.exception.DataException;

import org.gvsig.fmap.dal.feature.EditableFeature;

import org.gvsig.fmap.dal.feature.Feature;

import org.gvsig.fmap.geom.exception.CreateGeometryException;

import org.gvsig.geoprocess.core.MapTools;

import org.gvsig.sextante.app.algorithm.base.util.GeometryUtil;

import org.gvsig.sextante.app.algorithm.base.util.JTSFacade;

/**

 * Buffer operation

 * @author <a href="mailto:nachobrodin@gmail.com">Nacho Brodin</a>

 */

public class InOutBufferOperation extends BufferOperation {

        /**

         * Builds an instance of this operation.

         * @param distance

         * @param layer

         * @param userDistance

         */

        public InOutBufferOperation(IDistance distance, IVectorLayer layer, double userDistance) {

                super(distance, layer, userDistance);

        }

        /*

         * (non-Javadoc)

         * @see org.gvsig.sextante.app.algorithm.base.core.GeometryOperation#invoke(org.gvsig.fmap.geom.Geometry, org.gvsig.fmap.dal.feature.Feature)

         */

        @SuppressWarnings("unchecked")

        public EditableFeature invoke(org.gvsig.fmap.geom.Geometry g, Feature feature) {

                GeometryFactory geomFact = new GeometryFactory();

                Geometry newGeom = null;

                Geometry previousExteriorRing = null;

                Geometry previousInteriorRing = null;

                Geometry originalGeometry = GeometryUtil.geomToJTS(g);

                Geometry inputParam = originalGeometry;

                distance.setFeature(feature);

                double bufferDistance = distance.getBufferDistance(userDistance, projection, MapTools.getDistanceUnits(), MapTools.getMapUnits());

                if(originalGeometry.getDimension() != 0)

                        inputParam = TopologyPreservingSimplifier.simplify(originalGeometry, bufferDistance / 10d);

                for(int i = 1; i <= numberOfRadialBuffers; i++) {

                        double distRing = i * bufferDistance;

                        BufferOp bufOp = new BufferOp(inputParam);

                        bufOp.setEndCapStyle(capBuffer == CAP_ROUND ? BufferParameters.CAP_ROUND : BufferParameters.CAP_SQUARE);

                        Geometry out = bufOp.getResultGeometry(distRing);

                        Geometry in = bufOp.getResultGeometry(-1 * distRing);

                        boolean collapsedInterior = verifyNilGeometry(in);

                        if(previousExteriorRing == null || previousInteriorRing == null){

                                if(collapsedInterior)

                                        newGeom = out;

                                else

                                        newGeom = JTSFacade.difference(out, in);

                        } else {

                                if(collapsedInterior) 

                                        newGeom = JTSFacade.difference(out, previousExteriorRing);

                                else {

                                        Geometry outRing = JTSFacade.difference(out, previousExteriorRing);

                                        Geometry inRing = JTSFacade.difference(previousInteriorRing, in);

                                        Geometry[] geomArray = new Geometry[]{outRing, inRing};

                                        newGeom = geomFact.createGeometryCollection(geomArray);

                                        //FMap doesnt work with GeometryCollection, so we try to pass to a MultiPolygon.

                                        ArrayList polygons = new ArrayList();

                                        Stack stack = new Stack();

                                        stack.push(newGeom);

                                        while(stack.size() != 0) {

                                                GeometryCollection geCol = (GeometryCollection) stack.pop();

                                                for(int j = 0; j < geCol.getNumGeometries(); j++) {

                                                        Geometry geometry = geCol.getGeometryN(j);

                                                        if(geometry instanceof GeometryCollection)

                                                                stack.push(geometry);

                                                        if(geometry instanceof Polygon)

                                                                polygons.add(geometry);

                                                }

                                        }

                                        Polygon[] pols = new Polygon[polygons.size()];

                                        polygons.toArray(pols);

                                        MultiPolygon newSolution = geomFact.createMultiPolygon(pols);

                                        newGeom = newSolution;

                                }

                        }

                        try {

                                lastEditFeature = persister.addFeature(newGeom, id, -1 * distRing, distRing);

                                id ++;

                        } catch (CreateGeometryException e) {

                                Sextante.addErrorToLog(e);

                        } catch (DataException e) {

                                Sextante.addErrorToLog(e);

                        }

                        previousExteriorRing = out;

                        if(!collapsedInterior)

                                previousInteriorRing = in;

                }

                return lastEditFeature;

        }

        /*

         * (non-Javadoc)

         * @see org.gvsig.sextante.app.algorithm.base.core.GeometryOperation#invoke(org.gvsig.fmap.geom.Geometry, org.gvsig.fmap.dal.feature.EditableFeature)

         */

        public void invoke(org.gvsig.fmap.geom.Geometry g, EditableFeature feature) {

                invoke(g, (Feature)feature);

        }

}