Application: gvSIG desktop

/*

 * Cresques Mapping Suite. Graphic Library for constructing mapping applications.

 * 

 * Copyright (C) 2004-5. 

 *

 * 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:

 * 

 * cresques@gmail.com

 */

package org.cresques.px.dxf;

import java.awt.geom.Point2D;

import java.util.Vector;

/**

 * Calcula puntos sobre un arco.

 * @author jmorell

 *

 */

public class DxfCalArcs {

        final boolean debug = true;

        Point2D coord1, coord2;

        Point2D center;

        double radio, empieza, acaba;

        double bulge;

        double d, dd, aci;

        Point2D coordAux;

        //private Point2D centralPoint;

        public DxfCalArcs(Point2D p1, Point2D p2, double bulge) {

                this.bulge = bulge;

                /*System.out.println("DxfCalArcs: p1 = " + p1);

                System.out.println("DxfCalArcs: p2 = " + p2);

                System.out.println("DxfCalArcs: bulge = " + bulge);*/

                if (bulge < 0.0) {

                        coord1 = p2;

                        coord2 = p1;

                        //System.out.println("DxfCalArcs: Bulge negativo; coord1 = " + coord1 + ", coord2 = " + coord2);

                } else {

                        coord1 = p1;

                        coord2 = p2;

                }

                calculate();

        }

        DxfCalArcs calculate() {

                d = Math.sqrt((coord2.getX()-coord1.getX())*(coord2.getX()-coord1.getX()) + (coord2.getY()-coord1.getY())*(coord2.getY()-coord1.getY()));

                //System.out.println("DxfCalArcs: distancia reducida = " + d);

                coordAux = new Point2D.Double((coord1.getX()+coord2.getX())/2.0, (coord1.getY()+coord2.getY())/2.0);

                //System.out.println("DxfCalArcs: punto medio = " + coordAux);                        

                double b = Math.abs(bulge);

                //System.out.println("DxfCalArcs: Bulge(valor absoluto) = " + b);

                double beta = Math.atan(b);

                //System.out.println("DxfCalArcs: Angulo beta(rad) = " + beta);

                //double beta = Math.atan(bulge);

                double alfa = beta*4.0;

                //System.out.println("DxfCalArcs: Angulo alfa(rad)(angulo que define el arco) = " + alfa);

                double landa = alfa/2.0;

                //System.out.println("DxfCalArcs: Angulo landa(rad) = " + landa);

                dd = (d/2.0)/(Math.tan(landa));

                radio = (d/2.0)/(Math.sin(landa));                

                //System.out.println("DxfCalArcs: radio del arco = " + radio);

                aci = Math.atan((coord2.getX()-coord1.getX())/(coord2.getY()-coord1.getY()));

                //System.out.println("DxfCalArcs: Acimut de coord1(pto origen) a coord2(pto final) = " + aci);

                double aciDegree = aci*180.0/Math.PI;

                //System.out.println("DxfCalArcs: Acimut en grados = " + aciDegree);

                if (coord2.getY() > coord1.getY()) {

                        aci += Math.PI;

                        //System.out.println("DxfCalArcs: La coord Y de coord2 es mayor que la");

                        //System.out.println("DxfCalArcs: coord Y de coord1, acimut = acimut + PI, nuevo acimut = " + aci);

                        aciDegree = aci*180.0/Math.PI;

                        //System.out.println("DxfCalArcs: Nuevo acimut en grados = " + aciDegree);

                }

                center = new Point2D.Double(coordAux.getX() + dd*Math.sin(aci+(Math.PI/2.0)), coordAux.getY() + dd*Math.cos(aci+(Math.PI/2.0)));

                //System.out.println("DxfCalArcs: El centro del arco es: centro = " + center);

                calculateEA(alfa);

                return this;                

        }

        void calculateEA(double alfa){

                empieza = Math.atan2(coord1.getY()-center.getY(), coord1.getX()-center.getX());

                acaba = (empieza + alfa);

                empieza = empieza*180.0/Math.PI;

                acaba = acaba*180.0/Math.PI;

                //System.out.println("DxfCalArcs: Acimut de inicio = " + empieza + ", Acimut de finalizacion = " + acaba);

                //System.out.println("Tener en cuenta que los angulos se miden en sentido antihorario.");

   }

        public Vector getPoints(double inc) {

                //System.out.println("Se incia el metodo que construye el arco.");

                //System.out.println("Todo el proceso anterior define los parametros para esta construccion.");

                Vector arc = new Vector();

                double angulo;

                int iempieza = (int) empieza + 1; // ojo aqui !!

                int iacaba = (int) acaba;

                //System.out.println("DxfCalArcs: Angulo entero de inicio: iempieza = " + iempieza + ", Angulo entero de finalizacion: iacaba = " + iacaba);

                if (empieza <= acaba) {

                        //System.out.println("El angulo de inicio es menor que el angulo de finalizacion.");

                        addNode(arc, empieza);

                        for (angulo = iempieza; angulo <= iacaba; angulo += inc) {

                                addNode(arc, angulo);

                        }

                        addNode(arc, acaba);

                } else {

                        //System.out.println("El angulo de inicio es mayor que el angulo de finalizacion.");

                        addNode(arc, empieza);

                        for (angulo = iempieza ; angulo <= 360; angulo += inc) {

                                addNode(arc, angulo);

                        }

                        for (angulo = 1; angulo <= iacaba; angulo += inc) {

                                addNode(arc, angulo);

                        }

                        addNode(arc, angulo);

                }

                Point2D aux = (Point2D)arc.get(arc.size()-1);

                double aux1 = Math.abs(aux.getX()-coord2.getX());

                double aux2 = Math.abs(aux.getY()-coord2.getY());

                /*if (aux1<=0.000005 && aux2<=0.000005) {

                        arc.remove(arc.size()-1);

                        arc.remove(arc.size()-1);

                        arc.add(coord2);

                }*/

                return arc;

        }

        /**

         * 050301, jmorell: M?todo para obtener el punto central del arco.

         * @return

         */

        public Vector getCentralPoint() {

                Vector arc = new Vector();

                if (empieza <= acaba) {

                        addNode(arc, (empieza+acaba)/2.0);

                } else {

                        addNode(arc, empieza);

                        double alfa = 360-empieza;

                        double beta = acaba;

                        double an = alfa + beta;

                        double mid = an/2.0;

                        if (mid<=alfa) {

                                addNode(arc, empieza+mid);

                        } else {

                                addNode(arc, mid-alfa);

                        }

                }

                return arc;

        }

        private void addNode(Vector arc, double angulo) {

                double yy = center.getY() + radio * Math.sin(angulo*Math.PI/180.0);

                double xx = center.getX() + radio * Math.cos(angulo*Math.PI/180.0);                

                arc.add(new Point2D.Double(xx,yy));

                //System.out.println("DxfCalArcs: A?ade el punto " + new Point2D.Double(xx,yy) + ", correspondiente al angulo " + angulo);

        }

}