import java.awt.event.*;
import javax.swing.*;
import java.util.*;

import javax.media.opengl.*;
import javax.media.opengl.glu.*;
import com.sun.opengl.util.*;

public class randomDemo//
        extends glskeleton//
        implements GLEventListener//
        , KeyListener//
{
    private GLU glu;
    
    //
    public randomDemo() {
    }
    
    public void run() {
        GLCapabilities caps = new GLCapabilities();
        GLJPanel canvas = new GLJPanel(caps);
        randomDemo demo = new randomDemo();
        canvas.addGLEventListener(demo);
        demo.setCanvas(canvas);
        demo.setDefaultListeners(demo);
        
//        JFrame.setDefaultLookAndFeelDecorated(true);
        JFrame frame = new JFrame("randomDemo");
        frame.setSize(400, 400);
        frame.setLocationRelativeTo(null);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        
        frame.getContentPane().add(canvas);
        frame.setVisible(true);
        canvas.requestFocusInWindow();
    }
    
    public static void main(String[] args) {
        new randomDemo().run();
    }
    
    public void init(GLAutoDrawable drawable) {
        GL gl = drawable.getGL();
        glu = new GLU();
        //
        gl.glClearColor(1.0f, 1.0f, 1.0f, 1.0f);
        gl.glShadeModel(GL.GL_SMOOTH);
    }
    
    public void display(GLAutoDrawable drawable) {
        GL gl = drawable.getGL();
	
	// java.util.Random
	/*
	  An instance of this class is used to generate a stream of
	  pseudorandom numbers. The class uses a 48-bit seed, which is
	  modified using a linear congruential formula. (See Donald
	  Knuth, The Art of Computer Programming, Volume 2, Section
	  3.2.1.)
	  nextBoolean
	  nextFloat
	  nextDouble
	  nextGaussian
	  nextInt
	  setSeed(long seed)
	 */
	Random ran = new Random();
        
        gl.glClear(GL.GL_COLOR_BUFFER_BIT);
        
        /* select white for all lines */
        gl.glColor3f(0.0f, 0.0f, 0.0f);
	gl.glPointSize(2.0f);
	gl.glBegin(GL.GL_POINTS);
	for(double x=0; x<400.0; x+=0.1){
	    //double y = ran.nextDouble()*100;
	    double y = ran.nextGaussian()*100;
	    gl.glVertex2d(x,y);
	}
	gl.glEnd();
        gl.glFlush();
    }
    
    public void reshape(GLAutoDrawable drawable, int x, int y, int w, int h) {
        GL gl = drawable.getGL();
        //
        gl.glViewport(0, 0, w, h);
        gl.glMatrixMode(GL.GL_PROJECTION);
        gl.glLoadIdentity();
        glu.gluOrtho2D(0.0, (double) w, 0.0, (double) h);
    }
    
    public void displayChanged(GLAutoDrawable drawable, boolean modeChanged,
            boolean deviceChanged) {
    }
        
    public void keyTyped(KeyEvent key) {
    }
    
    public void keyPressed(KeyEvent key) {
        switch (key.getKeyCode()) {
            case KeyEvent.VK_ESCAPE:
                super.runExit();
                break;
                
            default:
                break;
        }
    }
    
    public void keyReleased(KeyEvent key) {
    }
    
}