/*
 *  =====================================================================
 *  Plotter.java : A very simple Java plotter
 *
 *  Written By : David Chancogne (doc@isr.umd.edu)         September 1997 
 *  =====================================================================
 */

import java.awt.*;
import java.lang.*;

class Plotter extends Frame {

    Button QuitButton;
    Graphics g;

    public static void main(String args[]){
       System.out.println("Simple Plotter");

       // The main method just create an instance of the class
       Plotter p = new Plotter();
    }

    // The class constructor
    // Called upon creation of the object Plotter

    public Plotter() {

       setTitle("Simple Plotter");

       setLayout(new FlowLayout());
       QuitButton = new Button("Quit");
       add(QuitButton);

       resize(600,300);
       show();

       // Call paint() method to do plotting

       g = getGraphics();
       paint(g);
    }

    /*
     *  =======================================================
     *  paint() method : x will go from 0 to SCALE_X
     *                   y will go from SCALE_Y/2 to -SCALE_Y/2
     *  =======================================================
     */

    public void paint(Graphics g) {
    int SCALE_X = 10; // Maximum value of x coordinate.
    int SCALE_Y = 30; // Range of y-coordinate values.
    int MIN_X   = 10; // Parameters used to calculate coordinates in the window
    int MAX_X   = 510;
    int DELTA_X = MAX_X-MIN_X;
    int MIN_Y   = 60;
    int MAX_Y   = 260;
    int DELTA_Y = MAX_Y-MIN_Y;

    int prev_x_pt=0;
    int prev_y_pt=0;

        // Draw axis in black

        g.setColor(Color.black);
        g.drawLine( MIN_X, MIN_Y+DELTA_Y/2, MAX_X, MIN_Y+DELTA_Y/2 );
        g.drawLine( MIN_X, MIN_Y, MIN_X, MAX_Y);

        // Change color to red for plotting

        g.setColor(Color.red);

        // Calculate the original point in pixel system

        double y_org = FunctionToPlot(0);
        prev_x_pt = MIN_X;
        prev_y_pt = (int)(MIN_Y + (DELTA_Y)/2 - (DELTA_Y)*y_org/SCALE_Y);

        // Loop on x
        // The loop is done on x calculated in pixel system.
        // Then x is converted in a value in 0 to SCALE_X
        // The corresponding y is evaluated (call to FunctionToPlot())
        // Y is converted back in pixel system.
        // We then can draw a line between previous and current point.

        for (int x_pt=MIN_X ; x_pt < MAX_X+1 ; x_pt++) {
        double x = (double)((double)(x_pt-MIN_X)*(double)SCALE_X/(double)(DELTA_X));
        double y = FunctionToPlot(x);
        int y_pt = (int)(MIN_Y + (DELTA_Y)/2 - (DELTA_Y)*y/SCALE_Y);

            g.drawLine(prev_x_pt, prev_y_pt, x_pt, y_pt);
            prev_x_pt = x_pt;
            prev_y_pt = y_pt;
        }
    }

    // The event handler (jdk1.0) For the "Quit" button

    public  boolean action (Event event, Object object) {
        if (event.target == QuitButton) {
            System.exit(0);
        }
        return true;
    }

    // The function to plot

    public double FunctionToPlot(double x) {
    double X_INT = 10;
    double V_INT = 10;
    double W = Math.sqrt(10);

       return (double)(X_INT*Math.cos(W*x)+V_INT*Math.sin(W*x)/W);
    }
}