Application: gvSIG desktop » gvSIG tools: Vector editing

/**

 * gvSIG. Desktop Geographic Information System.

 *

 * Copyright ? 2007-2015 gvSIG Association

 *

 * 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., 51 Franklin Street, Fifth Floor, Boston,

 * MA  02110-1301, USA.

 *

 * For any additional information, do not hesitate to contact us

 * at info AT gvsig.com, or visit our website www.gvsig.com.

 */

package org.gvsig.vectorediting.lib.prov.trimline.operation;

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

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

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

import org.gvsig.fmap.geom.Geometry;

import org.gvsig.fmap.geom.GeometryLocator;

import org.gvsig.fmap.geom.GeometryManager;

import org.gvsig.fmap.geom.aggregate.MultiCurve;

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

import org.gvsig.fmap.geom.operation.GeometryOperationException;

import org.gvsig.fmap.geom.operation.GeometryOperationNotSupportedException;

import org.gvsig.fmap.geom.primitive.Arc;

import org.gvsig.fmap.geom.primitive.Curve;

import org.gvsig.fmap.geom.primitive.Point;

import org.gvsig.tools.dispose.DisposableIterator;

import org.gvsig.tools.locator.LocatorException;

/**

 * Operation to trim arcs.

 * 

 * @author llmarques

 *

 */

public class ArcTrimLineOperation implements TrimLineOperation {

    /*

     * Strategy:

     * 

     * 1. Get arc segments between arc and boundary objects.

     * 2. Determinate what segment of arc must be deleted

     * 3. Rebuild arc taking into account the segment that must be deleted

     */

    public MultiCurve trimLine(Curve curveToTrim, Point insertedPoint,

        FeatureSelection boundaryObjects)

        throws GeometryOperationNotSupportedException,

        GeometryOperationException, DataException, CreateGeometryException,

        LocatorException {

        final Arc arcToTrim = (Arc) curveToTrim;

        GeometryManager geoManager = GeometryLocator.getGeometryManager();

        int subtype = arcToTrim.getGeometryType().getSubType();

        MultiCurve segmentedArc = geoManager.createMultiCurve(subtype);

        segmentedArc.addCurve(curveToTrim);

        DisposableIterator it = boundaryObjects.fastIterator();

        while (it.hasNext()) {

            Feature feature = (Feature) it.next();

            Geometry geometry = feature.getDefaultGeometry();

            Geometry tmpDifference = segmentedArc.difference(geometry);

            if (tmpDifference instanceof MultiCurve) {

                segmentedArc = (MultiCurve) tmpDifference;

            }

        }

        int index = 0;

        Curve arc;

        double minDistance = Double.POSITIVE_INFINITY;

        for (int i = 0; i < segmentedArc.getPrimitivesNumber(); i++) {

            arc = segmentedArc.getCurveAt(i);

            double distance = arc.distance(insertedPoint);

            if (distance < minDistance) {

                index = i;

                minDistance = distance;

            }

        }

        MultiCurve trimmedArc = geoManager.createMultiCurve(subtype);

        Point center = arcToTrim.getCenterPoint();

        // If Arc#getCenter() return null, we will have to use this "trick" to

        // get arc center.

        if (center == null) {

            center =

                geoManager.createPoint(arcToTrim.getEnvelope().getCenter(0),

                    arcToTrim.getEnvelope().getCenter(1), subtype);

        }

        double radius = center.distance(arcToTrim.getInitPoint());

        Curve tmpCurve = null;

        for (int i = 0; i < segmentedArc.getPrimitivesNumber(); i++) {

            if (i == index) {

                if (tmpCurve != null) {

                    trimmedArc.addCurve(tmpCurve);

                    tmpCurve = null;

                }

                continue;

            }

            if (tmpCurve != null) {

                tmpCurve =

                    union(center, radius, tmpCurve, segmentedArc.getCurveAt(i));

            } else {

                tmpCurve = segmentedArc.getCurveAt(i);

            }

        }

        if (tmpCurve != null) {

            trimmedArc.addCurve(tmpCurve);

        }

        return trimmedArc;

    }

    private Arc union(Point center, double radius, Curve curveA, Curve curveB)

        throws GeometryOperationNotSupportedException,

        GeometryOperationException, CreateGeometryException, LocatorException {

        int subtype1 = curveA.getGeometryType().getSubType();

        int subtype2 = curveB.getGeometryType().getSubType();

        Arc arc1 =

            TrimLineOperationUtils.createArc(center, radius,

                curveA.getVertex(0),

                curveA.getVertex(curveA.getNumVertices() - 1), subtype1);

        Arc arc2 =

            TrimLineOperationUtils.createArc(center, radius,

                curveB.getVertex(0),

                curveB.getVertex(curveB.getNumVertices() - 1), subtype1);

        if (subtype1 == subtype2) {

            double Xcenter1 = arc1.getCenterPoint().getX();

            double Ycenter1 = arc1.getCenterPoint().getY();

            double Xcenter2 = arc2.getCenterPoint().getX();

            double Ycenter2 = arc2.getCenterPoint().getY();

            double differenceX = Xcenter1 - Xcenter2;

            double differenceY = Ycenter1 - Ycenter2;

            if (Math.abs(differenceX) <= 0.001

                && Math.abs(differenceY) <= 0.001) {

                Point tmpCenter = arc1.getCenterPoint();

                double tmpRadius = center.distance(arc1.getInitPoint());

                return TrimLineOperationUtils.createArc(tmpCenter, tmpRadius,

                    arc1.getInitPoint(), arc2.getEndPoint(), subtype1);

            }

        }

        return null;

    }

}