| gvSIG desktop 1

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

 *

 * Copyright (C) 2004 IVER T.I. and 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.

 *

 * For more information, contact:

 *

 *  Generalitat Valenciana

 *   Conselleria d'Infraestructures i Transport

 *   Av. Blasco Ib??ez, 50

 *   46010 VALENCIA

 *   SPAIN

 *

 *      +34 963862235

 *   gvsig@gva.es

 *      www.gvsig.gva.es

 *

 *    or

 *

 *   IVER T.I. S.A

 *   Salamanca 50

 *   46005 Valencia

 *   Spain

 *

 *   +34 963163400

 *   dac@iver.es

 */

package org.gvsig.fmap.geom.primitive;

import java.awt.geom.Point2D;

import java.util.ArrayList;

import org.cresques.cts.IProjection;

import org.gvsig.fmap.geom.GeometryManager;

import org.gvsig.fmap.geom.handler.AbstractHandler;

import org.gvsig.fmap.geom.handler.FinalHandler;

import org.gvsig.fmap.geom.handler.Handler;

import org.gvsig.fmap.geom.type.GeometryType;

/**

 * Spline2D.

 *

 * @author Vicente Caballero Navarro

 */

public class Spline2D extends Curve2D implements Curve {

        private static final long serialVersionUID = 1L;

        private static GeometryType geomType = GeometryManager.getInstance()

        .registerGeometryType(Spline2D.class);        

        public static int CODE = geomType.getType();        

        private Point2D[] points;

        /**

         * Crea un nuevo FPolyline2D.

         *

         * @param gpx GeneralPathX.

         */

        public Spline2D(String id, IProjection projection, Point2D[] ps) {

                super(id, projection, getGeneralPathX(ps));

                points=ps;

        }

        private static GeneralPathX getGeneralPathX(Point2D[] ps) {

                GeneralPathX gpx=new GeneralPathX();

                int num=ps.length;

                double[] px=new double[num];

            double[] py=new double[num];

            for (int i=0;i<num;i++) {

                    Point2D p=ps[i];

                    px[i]=p.getX();

                    py[i]=p.getY();

            }

            Spline splineX = new Spline(px);

        Spline splineY = new Spline(py);

        gpx.moveTo(px[0],py[0]);

        for (int i = 0; i < px.length - 1; i++) {

            for (int t = 1; t < 31; t++) {

                double x1 = splineX.fn(i, ((double) t) / 30.0);

                double y1 = splineY.fn(i, ((double) t) / 30.0);

                gpx.lineTo(x1,y1);

            }

        }

        if (ps[0].getX()==ps[ps.length-1].getX() && ps[0].getY()==ps[ps.length-1].getY())

                gpx.closePath();

                return gpx;

        }

        /**

         * @see org.gvsig.fmap.geom.primitive.FShape#getShapeType()

         */

        public int getShapeType() {

                return FShape.LINE;

        }

        /* (non-Javadoc)

         * @see com.iver.cit.gvsig.fmap.core.FShape#cloneFShape()

         */

        public FShape cloneFShape() {

                return new Spline2D(id, projection, points);

        }

        /* (non-Javadoc)

         * @see com.iver.cit.gvsig.fmap.core.FShape#getStretchingHandlers()

         */

        public Handler[] getStretchingHandlers() {

                ArrayList handlers = new ArrayList();

                for (int i=0;i<points.length;i++) {

                        handlers.add(new PointHandler(i, points[i].getX(), points[i].getY()));

                }

                return (Handler[]) handlers.toArray(new Handler[0]);

        }

        /* (non-Javadoc)

         * @see com.iver.cit.gvsig.fmap.core.FShape#getSelectHandlers()

         */

        public Handler[] getSelectHandlers() {

                ArrayList handlers = new ArrayList();

                for (int i=0;i<points.length;i++) {

                        Point2D p=points[i];

                        handlers.add(new PointSelHandler(i, p.getX(), p.getY()));

                }

                return (Handler[]) handlers.toArray(new Handler[0]);

        }

        /**

         * DOCUMENT ME!

         *

         * @author Vicente Caballero Navarro

         */

        class PointHandler extends AbstractHandler implements FinalHandler{

                /**

                 * Crea un nuevo PointHandler.

                 *

                 * @param x DOCUMENT ME!

                 * @param y DOCUMENT ME!

                 */

                public PointHandler(int i,double x, double y) {

                        point = new Point2D.Double(x,y);

                        index=i;

                }

                /**

                 * DOCUMENT ME!

                 *

                 * @param x DOCUMENT ME!

                 * @param y DOCUMENT ME!

                 *

                 * @return DOCUMENT ME!

                 */

                public void move(double x, double y) {

                        point.setLocation(point.getX()+x,point.getY()+y);

                        //TODO falta actualizar el GeneralPathX

                }

                /**

                 * @see org.gvsig.fmap.geom.handler.Handler#set(double, double)

                 */

                public void set(double x, double y) {

                        point.setLocation(x,y);

                        //TODO falta actualizar el GeneralPathX

                }

        }

        /**

         * DOCUMENT ME!

         *

         * @author Vicente Caballero Navarro

         */

        class PointSelHandler extends AbstractHandler implements FinalHandler{

                /**

                 * Crea un nuevo PointHandler.

                 *

                 * @param x DOCUMENT ME!

                 * @param y DOCUMENT ME!

                 */

                public PointSelHandler(int i,double x, double y) {

                        point = new Point2D.Double(x,y);

                        index=i;

                }

                /**

                 * DOCUMENT ME!

                 *

                 * @param x DOCUMENT ME!

                 * @param y DOCUMENT ME!

                 *

                 * @return DOCUMENT ME!

                 */

                public void move(double x, double y) {

                        point.setLocation(point.getX()+x,point.getY()+y);

                        points[index]=point;

                        gp=getGeneralPathX(points);

                }

                /**

                 * @see org.gvsig.fmap.geom.handler.Handler#set(double, double)

                 */

                public void set(double x, double y) {

                        point.setLocation(x,y);

                        points[index]=point;

                        gp=getGeneralPathX(points);

                }

        }

         static class Spline {

                    private double y[];

                    private double y2[];

                    /**

                     * The constructor calculates the second derivatives of the interpolating function

                     * at the tabulated points xi, with xi = (i, y[i]).

                     * Based on numerical recipes in C, http://www.library.cornell.edu/nr/bookcpdf/c3-3.pdf .

                     * @param y Array of y coordinates for cubic-spline interpolation.

                     */

                    public Spline(double y[]) {

                            this.y = y;

                            int n = y.length;

                            y2 = new double[n];

                            double u[] = new double[n];

                            for (int i = 1; i < n - 1; i++) {

                                    y2[i] = -1.0 / (4.0 + y2[i - 1]);

                                    u[i] = (6.0 * (y[i + 1] - 2.0 * y[i] + y[i - 1]) - u[i - 1]) / (4.0 + y2[i - 1]);

                            }

                            for (int i = n - 2; i >= 0; i--) {

                                    y2[i] = y2[i] * y2[i + 1] + u[i];

                            }

                    }

                    /**

                     * Returns a cubic-spline interpolated value y for the point between

                     * point (n, y[n]) and (n+1, y[n+1), with t ranging from 0 for (n, y[n])

                     * to 1 for (n+1, y[n+1]).

                     * @param n The start point.

                     * @param t The distance to the next point (0..1).

                     * @return A cubic-spline interpolated value.

                     */

                    public double fn(int n, double t) {

                            return t * y[n + 1] - ((t - 1.0) * t * ((t - 2.0) * y2[n] - (t + 1.0) * y2[n + 1])) / 6.0 + y[n] - t * y[n];

                    }

            }

}