creating a BufferedImage from a drawing

[chappa]

Hi,


I have a programme that draws lines. However these lines (on faster machines) are drawed all at once. I would like to create a BufferedImage that I can set a timer with so the process of painting can be reviewed.

I have read the sun documentation ( this and this) on how to create a BufferedImage but I can still not figure out how to do this for my programme.

Any help is greatly appreciated.

 
import java.awt.*;  
import java.awt.event.*;  
import javax.swing.*;  
  
public class Success2  extends JPanel {  
	  
    // the contents of the window  
    JButton eatMeButton, drinkmeButton;  
    Circle circ=new Circle();  
    ActionListener al = new myButtonListener(circ);  
  
    final static Dimension BUTTON_SIZE = new Dimension(125,75);  
    final static Dimension WINDOW_SIZE = new Dimension(1024,768);  
    final static Dimension CIRC_SIZE = new Dimension(900,900);  
  
    public Success2() {  
        setLayout(new BoxLayout(this, BoxLayout.PAGE_AXIS));  
  
        // sandwich the buttonBox between two layers of stretchy glue  
        Box buttonBox = Box.createHorizontalBox();  
        add(Box.createVerticalGlue());  
        add(buttonBox);  
        add(Box.createVerticalGlue());  
  
        eatMeButton = new JButton("m1=1500");  
        eatMeButton.addActionListener(al);  
        eatMeButton.setPreferredSize(BUTTON_SIZE);  
        drinkmeButton = new JButton("drink me");  
        drinkmeButton.setPreferredSize(BUTTON_SIZE);  
         
        circ.setPreferredSize(new Dimension(CIRC_SIZE.height, CIRC_SIZE.height));  
  
  
        buttonBox.add(Box.createHorizontalGlue());  
        buttonBox.add(circ);  
        buttonBox.add(Box.createHorizontalGlue());  
        buttonBox.add(eatMeButton);  
        buttonBox.add(Box.createHorizontalGlue());  
        buttonBox.add(drinkmeButton);  
        buttonBox.add(Box.createHorizontalGlue());  
  
    }  
  
  
  
    // the circle  
  
     static class Circle extends JPanel {  
  
        int m1=6000;  
        @Override  
        public void paintComponent(Graphics g) {  
            g.clearRect(0, 0, this.getWidth(), this.getHeight());  
            g.setColor(Color.red);  
            Graphics2D gg = (Graphics2D)g;  
        int m = 200000;  
        //int m1 = 6000;  
        int m2 = 8000;  
        int b = 900;  
        int h = 900;  
  
  
        double gamma = 6.67;  
        double r = 15;  
        double r2 = 20;  
        double vx = 0;  
        double vx2 = 0;  
        double alpha = 0;  
        double alpha2 = 0;  
        double alpha3 = 0;  
        double alpha4 = 0;  
        double x = r;  
        double x2 = r2;  
        double y = 0;  
        double y2 = 0;  
        double mittelpunktx = b/2;  
        double mittelpunkty = h/2;  
        double vy = 0.0001 * Math.sqrt(1000 * gamma * m / r);  
        double vy2 = 0.0001 * Math.sqrt(1000* gamma * m / r2);  
        double tend = 500;  
        double t = 0;  
        double pi = 4*Math.atan(1);  
        double deltat = 0.01;  
        double result = 0;  
  
        while (t <= tend) {  
  
            t = t + deltat;  
            r = Math.sqrt(x * x + y * y);  
            r2 = Math.sqrt(x2 * x2 + y2 * y2);  
  
            double posx = mittelpunktx + x;  
            double posy = mittelpunkty + y;  
            double posx2 = mittelpunktx + x2;  
            double posy2 = mittelpunkty + y2;  
            double poswechselx = posx2 - posx;  
            double poswechsely = posy2 - posy;  
            double rwechselq = poswechselx * poswechselx + poswechsely * poswechsely;  
  
            double a = 0.00001 * gamma * ((m / r) / r);  
            double a2 = 0.00001 * gamma * ((m / r2) / r2);  
            double avon1auf2 = 0.00001 * gamma * (m2 / rwechselq);  
            double avon2auf1 = 0.00001 * gamma * (m1 / rwechselq);  
  
            alpha = winkel(x,y,alpha);  
            alpha2 = winkel(x2, y2, alpha2);  
            alpha3 = winkel(poswechselx, poswechsely, alpha3);  
            alpha4 = alpha3 + pi;  
  
            double ax = a * Math.cos(alpha);  
            double ay = a * Math.sin(alpha);  
            double ax2 = a2 * Math.cos(alpha2);  
            double ay2 = a2 * Math.sin(alpha2);  
            double ax3 = avon1auf2 * Math.cos(alpha3);  
            double ay3 = avon1auf2 * Math.sin(alpha3);  
            double ax4 = avon2auf1 * Math.cos(alpha4);  
            double ay4 = avon2auf1 * Math.sin(alpha4);  
  
            ax = ax + ax3;  
            ay = ay + ay3;  
            ax2 = ax2 + ax4;  
            ay2 = ay2 + ay4;  
            vx = vx - ax * deltat;  
            vy = vy - ay * deltat;  
            x = x + vx * deltat;  
            y = y + vy * deltat;  
            vx2 = vx2 - ax2 * deltat;  
            vy2 = vy2 - ay2 * deltat;  
            x2 = x2 + vx2 * deltat;  
            y2 = y2 + vy2 * deltat;  
  
            double finalx = skalierenx(posx);  
            double finaly = skaliereny(posy);  
            double finalx2 = skalierenx2(posx2);  
            double finaly2 = skaliereny2(posy2);  
            double finalmittelpunktx = skalierenx(mittelpunktx);  
            double finalmittelpunkty = skaliereny(mittelpunkty);  

			
                 
  
            g.setColor(Color.blue);  
            g.drawLine((int)(finalx),(int)(finaly),(int)(finalx),(int)(finaly));  
            g.setColor(Color.red);  
            g.drawLine((int)(finalx2),(int)(finaly2),(int)(finalx2),(int)(finaly2));  
            g.drawLine((int)(finalmittelpunktx),(int)(finalmittelpunkty),(int)(finalmittelpunktx),(int)(finalmittelpunkty));  
        //  g.drawOval((int)(finalx),(int)(finaly),);  
            }  
        }  
public double winkel(double xposition, double yposition, double result){  
    result = Math.atan(yposition / xposition);  
    double pi = 4*Math.atan(1);  
    if ((xposition < 0) && (yposition < 0)) {  
        result = result + pi;  
    }  
    if ((xposition < 0 ) && (yposition > 0)){  
        result = result + pi;  
    }  
    if ((xposition > 0) && (yposition <0)) {  
        result = result + 2*pi;  
    }  
    return result;  
        }  
  
  
public double skalierenx(double posx){  
    double minPointX = 508.0;  
    double maxPointX = 366.594;  
    double screenX = (posx - minPointX) * getWidth() / (maxPointX - minPointX);  
  
    return screenX;  
        }  
public double skaliereny(double posy){  
    double minPointY = 497.66;  
    double maxPointY = 337.468;  
    double screenY = (posy - minPointY) * getWidth() / (maxPointY - minPointY);  
  
    return screenY;  
        }  
public double skalierenx2(double posx2){  
    double minPointX2 = 508.0;  
    double maxPointX2 = 366.594;  
    double screenX2 = (posx2 - minPointX2) * getWidth() / (maxPointX2 - minPointX2);  
  
    return screenX2;  
        }  
public double skaliereny2(double posy2){  
    double minPointY2 = 497.66;  
    double maxPointY2 = 337.468;  
    double screenY2 = (posy2 - minPointY2) * getWidth() / (maxPointY2 - minPointY2);  
  
    return screenY2;  
        }  
    }  
  
    private static void createAndShowGUI() {  
        JFrame frame = new JFrame("Success2");  
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);  
  
        JComponent newContentPane = new Success2();  
        frame.setContentPane(newContentPane);  
  
        frame.setPreferredSize(WINDOW_SIZE);  
        frame.pack();  
        frame.setVisible(true);  
    }  
    public static void main(String[] args) {  
        javax.swing.SwingUtilities.invokeLater(new Runnable() {  
            public void run() {  
                createAndShowGUI();  
            }  
        });  
    }  
class myButtonListener implements ActionListener{  
    Circle c;  
   myButtonListener(Circle c){  
       this.c=c;  
   }  
    public void actionPerformed(ActionEvent ae){  
        c.m1 = 8000;  
        c.repaint();  
        }  
    }  
  
}

Thank you

chappa

[hardwired]

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

public class Success2Rx implements Runnable {
    CirclePanel circlePanel = new CirclePanel();
    int width = circlePanel.getPreferredSize().width;
    CircleModel circleModel = new CircleModel(width);
    BufferedImage image;
    JLabel label;
    Thread thread;
    long delay = 10;
    boolean running = false;
    
    private boolean advance() {
        if(!circleModel.isFinished()) {
            double[] data = circleModel.getData();
            double finalx            = data[0];
            double finaly            = data[1];
            double finalx2           = data[2];
            double finaly2           = data[3];
            double finalmittelpunktx = data[4];
            double finalmittelpunkty = data[5];
            Graphics2D g2 = image.createGraphics();
            g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
                                RenderingHints.VALUE_ANTIALIAS_ON);
            g2.setColor(Color.blue);
            g2.drawLine((int)(finalx),(int)(finaly),
                       (int)(finalx),(int)(finaly));
            g2.setColor(Color.red);
            g2.drawLine((int)(finalx2),(int)(finaly2),
                       (int)(finalx2),(int)(finaly2));
            g2.drawLine((int)(finalmittelpunktx),(int)(finalmittelpunkty),
                       (int)(finalmittelpunktx),(int)(finalmittelpunkty));
            g2.dispose();
            label.repaint();
            return false;
        }
        return true;
    }

    public void run() {
        long start = System.currentTimeMillis();
        while(running) {
            try {
                Thread.sleep(delay);
            } catch(InterruptedException e) {
                System.out.println("interrupt");
            }
            if(advance()) {
                stop();
            }
        }
        long end = System.currentTimeMillis();
        System.out.printf("Actual run time: %f seconds.%n",
                           (end - start)/1000.0);
    }

    private void start() {
        double deltat = circleModel.deltat;
        double cycles = circleModel.tend;
        double frames = cycles/deltat;
        long framesPerSecond = 1000/delay;
        double totalTime = frames/framesPerSecond;
        System.out.printf("Expected run time for deltat: %.3f, " +
                          "tend: %.0f and delay: %d is %.3f seconds.%n",
                           deltat, cycles, delay, totalTime);
        if(!running) {
            running = true;
            thread = new Thread(this);
            thread.setPriority(Thread.NORM_PRIORITY);
            thread.start();
        }
    }

    public void stop() {
        running = false;
        if(thread != null) {
            thread.interrupt();
        }
        thread = null;
    }

    private void eraseImage() {
        Graphics2D g2 = image.createGraphics();
        g2.setBackground(Color.white);
        g2.clearRect(0,0,image.getWidth(),image.getHeight());
        g2.dispose();
    }

    private JPanel getCenterContent() {
        JPanel panel = new JPanel(new GridLayout(1,0,2,0));
        panel.add(circlePanel);
        Dimension d = circlePanel.getPreferredSize();
        image = getCompatibleImage(d.width, d.height);
        eraseImage();
        panel.add(label = new JLabel(new ImageIcon(image)));
        return panel;
    }

    private BufferedImage getCompatibleImage(int w, int h) {
        return GraphicsEnvironment.getLocalGraphicsEnvironment()
                                  .getDefaultScreenDevice()
                                  .getDefaultConfiguration()
                                  .createCompatibleImage(w, h);
    }

    private JPanel getButtonPanel() {
        String[] ids = { "Change m1", "Start", "Stop", "Erase" };
        ActionListener al = new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                String id = e.getActionCommand();
                if(id.startsWith("Change")) {
                    circlePanel.setM1(1500);
                    circlePanel.repaint();
                    if(!circleModel.isFinished()) {
                        stop();
                    }
                    circleModel.reset();
                    circleModel.setM1(1500);
                    ((JButton)e.getSource()).setEnabled(false);
                }
                if(id.equals("Start")) {
                    start();
                }
                if(id.equals("Stop")) {
                    stop();
                }
                if(id.equals("Erase")) {
                    eraseImage();
                    label.repaint();
                }
            }
        };
        JPanel panel = new JPanel();
        for(int i = 0; i < ids.length; i++) {
            JButton button = new JButton(ids[i]);
            button.setActionCommand(ids[i]);
            button.addActionListener(al);
            panel.add(button);
        }
        return panel;
    }

    public static void main(String[] args) {
        Success2Rx app = new Success2Rx();
        JFrame frame = new JFrame("Success2Rx");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.add(app.getCenterContent());
        frame.add(app.getButtonPanel(), "Last");
        frame.pack();
        frame.setVisible(true);
    }
}

class CircleModel {
    int width;
    int m1=6000;

    public CircleModel(int width) {
        this.width = width;
    }

    int m = 200000;
    int m2 = 8000;
    int b = 900;
    int h = 900;

    double gamma = 6.67;
    double r = 15;
    double r2 = 20;
    double vx = 0;
    double vx2 = 0;
    double alpha = 0;
    double alpha2 = 0;
    double alpha3 = 0;
    double alpha4 = 0;
    double x = r;
    double x2 = r2;
    double y = 0;
    double y2 = 0;
    double mittelpunktx = b/2;
    double mittelpunkty = h/2;
    double vy = 0.0001 * Math.sqrt(1000 * gamma * m / r);
    double vy2 = 0.0001 * Math.sqrt(1000* gamma * m / r2);
    double tend = 500;
    double t = 0;
    double pi = 4*Math.atan(1);
    double deltat = //0.01;
                    0.1;
//    double result = 0;

    public double[] getData() {
        t = t + deltat;
        r = Math.sqrt(x * x + y * y);
        r2 = Math.sqrt(x2 * x2 + y2 * y2);

        double posx = mittelpunktx + x;
        double posy = mittelpunkty + y;
        double posx2 = mittelpunktx + x2;
        double posy2 = mittelpunkty + y2;
        double poswechselx = posx2 - posx;
        double poswechsely = posy2 - posy;
        double rwechselq = poswechselx * poswechselx +
                           poswechsely * poswechsely;

        double a = 0.00001 * gamma * ((m / r) / r);
        double a2 = 0.00001 * gamma * ((m / r2) / r2);
        double avon1auf2 = 0.00001 * gamma * (m2 / rwechselq);
        double avon2auf1 = 0.00001 * gamma * (m1 / rwechselq);

        alpha = winkel(x, y);
        alpha2 = winkel(x2, y2);
        alpha3 = winkel(poswechselx, poswechsely);
        alpha4 = alpha3 + pi;

        double ax = a * Math.cos(alpha);
        double ay = a * Math.sin(alpha);
        double ax2 = a2 * Math.cos(alpha2);
        double ay2 = a2 * Math.sin(alpha2);
        double ax3 = avon1auf2 * Math.cos(alpha3);
        double ay3 = avon1auf2 * Math.sin(alpha3);
        double ax4 = avon2auf1 * Math.cos(alpha4);
        double ay4 = avon2auf1 * Math.sin(alpha4);

        ax = ax + ax3;
        ay = ay + ay3;
        ax2 = ax2 + ax4;
        ay2 = ay2 + ay4;
        vx = vx - ax * deltat;
        vy = vy - ay * deltat;
        x = x + vx * deltat;
        y = y + vy * deltat;
        vx2 = vx2 - ax2 * deltat;
        vy2 = vy2 - ay2 * deltat;
        x2 = x2 + vx2 * deltat;
        y2 = y2 + vy2 * deltat;

        double finalx = skalierenx(posx);
        double finaly = skaliereny(posy);
        double finalx2 = skalierenx2(posx2);
        double finaly2 = skaliereny2(posy2);
        double finalmittelpunktx = skalierenx(mittelpunktx);
        double finalmittelpunkty = skaliereny(mittelpunkty);
        return new double[] { finalx, finaly, finalx2, finaly2,
                              finalmittelpunktx, finalmittelpunkty };
    }

    public boolean isFinished() { return t > tend; }

    public void reset() {
        t = 0;
        r = 15; r2 = 20;
        alpha = alpha2 = alpha3 = alpha4 = 0;
        x = r; x2 = r2; y = y2 = 0;
        vx = vx2 = 0;
        vy = 0.0001 * Math.sqrt(1000 * gamma * m / r);
        vy2 = 0.0001 * Math.sqrt(1000* gamma * m / r2);
    }

    public void setM1(int n) { m1 = n; }

    private int getWidth() { return width; }

    private double winkel(double xposition, double yposition){
        double result = Math.atan(yposition / xposition);
        double pi = 4*Math.atan(1);
        if ((xposition < 0) && (yposition < 0)) {
            result = result + pi;
        }
        if ((xposition < 0 ) && (yposition > 0)){
            result = result + pi;
        }
        if ((xposition > 0) && (yposition <0)) {
            result = result + 2*pi;
        }
        return result;
    }

    private double skalierenx(double posx){
        double minPointX = 508.0;
        double maxPointX = 366.594;
        double screenX =
            (posx - minPointX) * getWidth() / (maxPointX - minPointX);

        return screenX;
    }

    private double skaliereny(double posy){
        double minPointY = 497.66;
        double maxPointY = 337.468;
        double screenY =
            (posy - minPointY) * getWidth() / (maxPointY - minPointY);

        return screenY;
    }

    private double skalierenx2(double posx2){
        double minPointX2 = 508.0;
        double maxPointX2 = 366.594;
        double screenX2 =
            (posx2 - minPointX2) * getWidth() / (maxPointX2 - minPointX2);

        return screenX2;
    }

    private double skaliereny2(double posy2){
        double minPointY2 = 497.66;
        double maxPointY2 = 337.468;
        double screenY2 =
            (posy2 - minPointY2) * getWidth() / (maxPointY2 - minPointY2);

        return screenY2;
    }
}

class CirclePanel extends JPanel {
    int m1=6000;

    @Override
    protected void paintComponent(Graphics g) {
        g.clearRect(0, 0, this.getWidth(), this.getHeight());
//        g.setColor(Color.red);
        Graphics2D gg = (Graphics2D)g;
        int m = 200000;
        //int m1 = 6000;
        int m2 = 8000;
        int b = 900;
        int h = 900;

        double gamma = 6.67;
        double r = 15;
        double r2 = 20;
        double vx = 0;
        double vx2 = 0;
        double alpha = 0;
        double alpha2 = 0;
        double alpha3 = 0;
        double alpha4 = 0;
        double x = r;
        double x2 = r2;
        double y = 0;
        double y2 = 0;
        double mittelpunktx = b/2;
        double mittelpunkty = h/2;
        double vy = 0.0001 * Math.sqrt(1000 * gamma * m / r);
        double vy2 = 0.0001 * Math.sqrt(1000* gamma * m / r2);
        double tend = 500;
        double t = 0;
        double pi = 4*Math.atan(1);
        double deltat = 0.01;
        double result = 0;

        while (t <= tend) {

            t = t + deltat;
            r = Math.sqrt(x * x + y * y);
            r2 = Math.sqrt(x2 * x2 + y2 * y2);

            double posx = mittelpunktx + x;
            double posy = mittelpunkty + y;
            double posx2 = mittelpunktx + x2;
            double posy2 = mittelpunkty + y2;
            double poswechselx = posx2 - posx;
            double poswechsely = posy2 - posy;
            double rwechselq = poswechselx * poswechselx +
                               poswechsely * poswechsely;

            double a = 0.00001 * gamma * ((m / r) / r);
            double a2 = 0.00001 * gamma * ((m / r2) / r2);
            double avon1auf2 = 0.00001 * gamma * (m2 / rwechselq);
            double avon2auf1 = 0.00001 * gamma * (m1 / rwechselq);

            alpha = winkel(x, y);
            alpha2 = winkel(x2, y2);
            alpha3 = winkel(poswechselx, poswechsely);
            alpha4 = alpha3 + pi;

            double ax = a * Math.cos(alpha);
            double ay = a * Math.sin(alpha);
            double ax2 = a2 * Math.cos(alpha2);
            double ay2 = a2 * Math.sin(alpha2);
            double ax3 = avon1auf2 * Math.cos(alpha3);
            double ay3 = avon1auf2 * Math.sin(alpha3);
            double ax4 = avon2auf1 * Math.cos(alpha4);
            double ay4 = avon2auf1 * Math.sin(alpha4);

            ax = ax + ax3;
            ay = ay + ay3;
            ax2 = ax2 + ax4;
            ay2 = ay2 + ay4;
            vx = vx - ax * deltat;
            vy = vy - ay * deltat;
            x = x + vx * deltat;
            y = y + vy * deltat;
            vx2 = vx2 - ax2 * deltat;
            vy2 = vy2 - ay2 * deltat;
            x2 = x2 + vx2 * deltat;
            y2 = y2 + vy2 * deltat;

            double finalx = skalierenx(posx);
            double finaly = skaliereny(posy);
            double finalx2 = skalierenx2(posx2);
            double finaly2 = skaliereny2(posy2);
            double finalmittelpunktx = skalierenx(mittelpunktx);
            double finalmittelpunkty = skaliereny(mittelpunkty);

            g.setColor(Color.blue);
            g.drawLine((int)(finalx),(int)(finaly),
                       (int)(finalx),(int)(finaly));
            g.setColor(Color.red);
            g.drawLine((int)(finalx2),(int)(finaly2),
                       (int)(finalx2),(int)(finaly2));
            g.drawLine((int)(finalmittelpunktx),(int)(finalmittelpunkty),
                       (int)(finalmittelpunktx),(int)(finalmittelpunkty));
            //  g.drawOval((int)(finalx),(int)(finaly),);
        }
    }

    public Dimension getPreferredSize() {
        return new Dimension(500,400);
    }

    public void setM1(int n) {
        m1 = n;
        repaint();
    }

    public double winkel(double xposition, double yposition){
        double result = Math.atan(yposition / xposition);
        double pi = 4*Math.atan(1);
        if ((xposition < 0) && (yposition < 0)) {
            result = result + pi;
        }
        if ((xposition < 0 ) && (yposition > 0)){
            result = result + pi;
        }
        if ((xposition > 0) && (yposition <0)) {
            result = result + 2*pi;
        }
        return result;
    }

    public double skalierenx(double posx){
        double minPointX = 508.0;
        double maxPointX = 366.594;
        double screenX =
            (posx - minPointX) * getWidth() / (maxPointX - minPointX);

        return screenX;
    }

    public double skaliereny(double posy){
        double minPointY = 497.66;
        double maxPointY = 337.468;
        double screenY =
            (posy - minPointY) * getWidth() / (maxPointY - minPointY);

        return screenY;
    }

    public double skalierenx2(double posx2){
        double minPointX2 = 508.0;
        double maxPointX2 = 366.594;
        double screenX2 =
            (posx2 - minPointX2) * getWidth() / (maxPointX2 - minPointX2);

        return screenX2;
    }

    public double skaliereny2(double posy2){
        double minPointY2 = 497.66;
        double maxPointY2 = 337.468;
        double screenY2 =
            (posy2 - minPointY2) * getWidth() / (maxPointY2 - minPointY2);

        return screenY2;
    }
}

[chappa]

Thank you, hardwired!