rotator3d.java

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/*
 * @(#)Rotator3D.java	1.4  98/12/03
 * 
 * Copyright 1993-1998 Sun Microsystems, Inc. 901 San Antonio Road, 
 * Palo Alto, California, 94303, U.S.A.  All Rights Reserved.
 * 
 * This software is the confidential and proprietary information of Sun
 * Microsystems, Inc. ("Confidential Information").  You shall not
 * disclose such Confidential Information and shall use it only in
 * accordance with the terms of the license agreement you entered into
 * with Sun.
 * 
 * CopyrightVersion 1.2
 * 
 */


import java.awt.*;
import java.awt.event.*;
import java.awt.image.BufferedImage;
import javax.swing.*;


/**
 * The Rotator3D class displays animated multi-colored 3D objects that are 
 * translated, rotated and scaled.  Color changes are demonstrated by using a
 * light source and shading.
 */
public class Rotator3D extends JApplet implements Runnable {

    private Objects3D objs[] = new Objects3D[3];
    private static final int[][][] polygons = 
             { 
        // Solid cube   
              {{5, 1, 15, 13, 21, 23, 15}, 
               {5, 2, 21, 13, 19, 27, 21},
               {5, 3, 23, 15, 17, 25, 23}, 
               {5, 4, 19, 13, 15, 17, 19},
               {5, 5, 27, 21, 23, 25, 27},
               {5, 6, 27, 19, 17, 25, 27}},
        // Polygonal faces cube
              {{5, 1, 21, 13, 19, 27, 21},
               {5, 5, 23, 15, 17, 25, 23}, 
               {4,0,15,14,16,15}, {7,6,16,14,13,12,18,17,16}, {4,0,12,19,18,12},
               {4,2,22,21,20,22}, {7,0,24,23,22,20,27,26,24}, {4,2,24,26,25,24},
               {4, 3, 15, 13, 23, 15}, {4, 0, 23, 13, 21, 23}, 
               {5, 0, 27, 26, 18, 19, 27}, {5, 4, 25, 17, 18, 26, 25}}, 
        // Octahedron
              {{4, 3, 18, 21, 16, 18}, {4, 1, 20, 16, 18, 20}, 
               {4, 1, 18, 21, 16, 18}, {4, 3, 20, 17, 19, 20}, 
               {4, 2, 20, 26, 27, 20}, {5, 3, 26, 18, 16, 27, 26}, 
               {5, 0, 17, 24, 25, 19, 17}, {4, 3, 21, 25, 24, 21}, 
               {4, 4, 18, 21, 22, 18}, {4, 2, 22, 21, 17, 22}, 
               {4, 5, 20, 23, 16, 20}, {4, 1, 20, 23, 19, 20}, 
               {4, 6, 21, 23, 16, 21}, {4, 4, 21, 23, 19, 21}, 
               {4, 5, 20, 18, 22, 20}, {4, 6, 20, 22, 17, 20}}
             };
    private static final double[][][] points = 
           { 
        // Points for solid cube & polygonal faces cube
            {{1, 0, 0}, {-1, 0, 0}, {0, 1, 0}, {0, -1, 0}, {0, 0, 1}, 
             {0, 0, -1}, {1, 0, 0}, {-1, 0, 0}, {0, 1, 0}, {0, -1, 0}, 
             {0, 0, 1}, {0, 0, -1}, {1, 1, 0}, {1, 1, 1}, {0, 1, 1}, 
             {-1, 1, 1}, {-1, 1, 0}, {-1, 1, -1}, {0, 1, -1}, {1, 1, -1}, 
             {1, -1, 0}, {1, -1, 1}, {0, -1, 1}, {-1, -1, 1}, {-1, -1, 0}, 
             {-1, -1, -1}, {0, -1, -1}, {1, -1, -1}},
        // Points for octahedron
            {{0, 0, 1}, {0, 0, -1}, {-0.8165, 0.4714, 0.33333},
             {0.8165, -0.4714, -0.33333}, {0.8165, 0.4714, 0.33333},
             {-0.8165, -0.4714, -0.33333}, {0, -0.9428, 0.3333},
             {0, 0.9428, -0.33333}, {0, 0, 1}, {0, 0, -1},
             {-0.8165, 0.4714, 0.33333}, {0.8165, -0.4714, -0.33333}, 
             {0.8165, 0.4714, 0.33333}, {-0.8165, -0.4714, -0.33333},  
             {0, -0.9428, 0.33333}, {0, 0.9428, -0.33333},  
             {-1.2247, -0.7071, 1}, {1.2247, 0.7071, -1}, 
             {0, 1.4142, 1}, {0, -1.4142, -1}, {-1.2247, 0.7071, -1}, 
             {1.2247, -0.7071, 1}, {0.61237, 1.06066, 0}, 
             {-0.61237, -1.06066, 0}, {1.2247, 0, 0}, 
             {0.61237, -1.06066, 0}, {-0.61237, 1.06066, 0}, {-1.2247, 0, 0}}
           }; 
    private static final int[][][] faces = 
           { 
         // Solid cube
             {{1, 1}, {1, 2}, {1, 3}, {1, 4}, {1, 0}, {1, 5}},
         // Polygonal faces cube
             {{1, 0}, {1, 1}, {3, 2, 3, 4}, {3, 5, 6, 7}, {2,8,9}, {2,10,11}},
         // Octahedron
             {{1, 2}, {1, 3}, {2, 4, 5}, {2, 6, 7}, {2, 8, 9}, 
              {2, 10, 11}, {2, 12, 13}, {2, 14, 15}},
           };
    private Thread thread;
    private BufferedImage bimg;


    public void init() {
        setBackground(Color.white);
    }


    // initializes the 3D objects
    public void reset(int w, int h) {
        objs[0] = new Objects3D(polygons[0], points[0], faces[0], w, h);
        objs[1] = new Objects3D(polygons[1], points[0], faces[1], w, h);
        objs[2] = new Objects3D(polygons[2], points[1], faces[2], w, h);
    }


    public void step(int w, int h) {
        for (int i = objs.length; i-- > 0; ) {
            if (objs[i] != null) {
                objs[i].step(w, h);
            }
        }
    }


    public void drawDemo(int w, int h, Graphics2D g2) {
        for (int i = objs.length; i-- > 0; ) {
            if (objs[i] != null) {
                objs[i].Draw(g2);
            }
        }
    }


    public Graphics2D createGraphics2D(int w, int h) {
        Graphics2D g2 = null;
        if (bimg == null || bimg.getWidth() != w || bimg.getHeight() != h) {
            bimg = (BufferedImage) createImage(w, h);
            reset(w, h);
        } 
        g2 = bimg.createGraphics();
        g2.setBackground(getBackground());
        g2.clearRect(0, 0, w, h);
        g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
                            RenderingHints.VALUE_ANTIALIAS_ON);
        return g2;
    }


    public void paint(Graphics g) {
	Dimension d = getSize();
        step(d.width, d.height);
        Graphics2D g2 = createGraphics2D(d.width, d.height);
        drawDemo(d.width, d.height, g2);
        g2.dispose();
        g.drawImage(bimg, 0, 0, this);
    }


    public void start() {
        thread = new Thread(this);
        thread.setPriority(Thread.MIN_PRIORITY);
        thread.start();
    }


    public synchronized void stop() {
        thread = null;
    }


    public void run() {
        Thread me = Thread.currentThread();
        while (thread == me) {
            repaint();
            try {
                thread.sleep(10);
            } catch (InterruptedException e) { break; }
        }
        thread = null;
    }



    /**
     * The Objects3D class creates a Solid Cube, Cube and Octahedron with 
     * polygonal faces.
     */
    public class Objects3D {
    
        private final int UP = 0;
        private final int DOWN = 1;
        private int[][] polygons;
        private int npoly;
        private double[][] points;
        private int npoint;
        private int[][] faces;
        private int nface;
        private int ncolour = 10;
        private Color[][] colours = new Color[ncolour][7];
        private double[] lightvec = {0, 1, 1}; 
        private double Zeye = 10;
        private double angle;
        private Matrix3D orient, tmp, tmp2, tmp3;
        private int scaleDirection;
        private double scale, scaleAmt;
        private double ix = 3.0, iy = 3.0;
        private double[][] rotPts;
        private int[][] scrPts;
        private int xx[] = new int[20];
        private int yy[] = new int[20];
        private double x, y;
        private int p, j;
        private int colour;
        private double bounce, persp;
    
     
        public Objects3D(int[][] polygons, 
                         double[][] points, 
                         int[][] faces, 
                         int w, 
                         int h) {
    
            this.polygons = polygons;
            this.points = points;
            this.faces = faces;
            npoly = polygons.length;
            npoint = points.length;
            nface = faces.length;
    
            x = w * Math.random();
            y = h * Math.random();
    
            ix = Math.random() > 0.5 ? ix : -ix;
            iy = Math.random() > 0.5 ? iy : -iy;
    
            rotPts = new double[npoint][3];
            scrPts = new int[npoint][2];

            /*
             * computes colors to produce shading effect 
             */
            for (int i = 0; i < ncolour; i++) {
                // white
                colours[i][0]= new Color(255 -(ncolour-1-i)*100/ncolour,
                    255 -(ncolour-1-i)*100/ncolour,255 
                    -(ncolour-1-i)*100/ncolour);
                // red