001    /*
002     * Copyright (C) 2008-2010 by Holger Arndt
003     *
004     * This file is part of the Universal Java Matrix Package (UJMP).
005     * See the NOTICE file distributed with this work for additional
006     * information regarding copyright ownership and licensing.
007     *
008     * UJMP is free software; you can redistribute it and/or modify
009     * it under the terms of the GNU Lesser General Public License as
010     * published by the Free Software Foundation; either version 2
011     * of the License, or (at your option) any later version.
012     *
013     * UJMP is distributed in the hope that it will be useful,
014     * but WITHOUT ANY WARRANTY; without even the implied warranty of
015     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
016     * GNU Lesser General Public License for more details.
017     *
018     * You should have received a copy of the GNU Lesser General Public
019     * License along with UJMP; if not, write to the
020     * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
021     * Boston, MA  02110-1301  USA
022     */
023    
024    package org.ujmp.gui.actions;
025    
026    import javax.swing.Action;
027    import javax.swing.JComponent;
028    
029    import org.ujmp.core.Matrix;
030    import org.ujmp.core.exceptions.MatrixException;
031    import org.ujmp.core.interfaces.GUIObject;
032    import org.ujmp.gui.MatrixGUIObject;
033    
034    public class MandelbrotMatrixAction extends AbstractMatrixAction {
035            private static final long serialVersionUID = 8708344146012762782L;
036    
037            public MandelbrotMatrixAction(JComponent c, MatrixGUIObject m, GUIObject v) {
038                    super(c, m, v);
039                    putValue(Action.NAME, "Mandelbrot Matrix");
040                    putValue(Action.SHORT_DESCRIPTION,
041                                    "creates a matrix from the mandelbrot set");
042            }
043    
044            public Object call() throws MatrixException {
045                    double xoffset = -.5;
046                    double yoffset = 0;
047                    double size = 2;
048                    int cells = 500;
049                    int iterations = 20;
050    
051                    Matrix m = Matrix.factory.zeros(cells, cells);
052                    for (int column = 0; column < cells; column++) {
053                            for (int row = 0; row < cells; row++) {
054                                    double x0 = xoffset - size / 2 + size * column / cells;
055                                    double y0 = yoffset - size / 2 + size * row / cells;
056                                    Complex z0 = new Complex(x0, y0);
057                                    double gray = iterations - calc(z0, iterations);
058                                    m.setAsDouble((gray - (iterations / 2)) / (iterations / 2),
059                                                    cells - 1 - row, column);
060                            }
061                    }
062                    m.showGUI();
063                    return m;
064            }
065    
066            public int calc(Complex c, int iterations) {
067                    Complex z = c;
068                    for (int i = 0; i < iterations; i++) {
069                            if (z.abs() > 2.0) {
070                                    return i;
071                            }
072                            z = z.times(z).plus(c);
073                    }
074                    return iterations;
075            }
076    
077    }
078    
079    class Complex {
080            double real = 0;
081    
082            double img = 0;
083    
084            public Complex(double real, double img) {
085                    this.real = real;
086                    this.img = img;
087            }
088    
089            public double abs() {
090                    return Math.sqrt(real * real + img * img);
091            }
092    
093            public Complex times(Complex c2) {
094                    double real2 = this.real * c2.real - this.img * c2.img;
095                    double img2 = this.img * c2.real + this.real * c2.img;
096                    return new Complex(real2, img2);
097            }
098    
099            public Complex plus(Complex c2) {
100                    double real = this.real + c2.real;
101                    double img = this.img + c2.img;
102                    return new Complex(real, img);
103            }
104    }