import java.awt.*;
import java.awt.image.*;
import java.net.*;
import java.util.*;

class Main extends Frame {
    Main() {
        super("Mandlebrot Set - CS474 Assignment");
        try {
            add(new MandelbrotCanvas(), BorderLayout.CENTER);
        } catch (Exception e) {
            e.printStackTrace();
        }
        setSize(600, 400);
        show();
    }

    static public void main(String[] args) {
        new Main();
    }
}

class MandelbrotCanvas extends Component {
    Image image;

    public void paint(Graphics g) {
        if (image == null ) {
            image = getToolkit().createImage(
                new MemoryImageSource(600, 400,
                generateColorModel(), generatePixels(600, 400), 0,600));
        }
        g.drawImage(image, 0, 0, this);
    }

    IndexColorModel generateColorModel() {
        byte[] r = new byte[16];
        byte[] g = new byte[16];
        byte[] b = new byte[16];

        r[0] = 0; g[0] = 0; b[0] = 0;
        r[1] = 0; g[1] = 0; b[1] = (byte)192;
        r[2] = 0; g[2] = 0; b[2] = (byte)255;
        r[3] = 0; g[3] = (byte)192; b[3] = 0;
        r[4] = 0; g[4] = (byte)255; b[4] = 0;
        r[5] = 0; g[5] = (byte)192; b[5] = (byte)192;
        r[6] = 0; g[6] = (byte)255; b[6] = (byte)255;
        r[7] = (byte)192; g[7] = 0; b[7] = 0;
        r[8] = (byte)255; g[8] = 0; b[8] = 0;
        r[9] = (byte)192; g[9] = 0; b[9] = (byte)192;
        r[10] = (byte)255; g[10] = 0; b[10] = (byte)255;
        r[11] = (byte)192; g[11] = (byte)192; b[11] = 0;
        r[12] = (byte)255; g[12] = (byte)255; b[12] = 0;
        r[13] = (byte)80; g[13] = (byte)80; b[13] = (byte)80;
        r[14] = (byte)192; g[14] = (byte)192; b[14] = (byte)192;
        r[15] = (byte)255; g[15] = (byte)255; b[15] = (byte)255;

        return new IndexColorModel(4, 16, r, g, b);
    }

    final float xmin = -2.0f;
    final float xmax = 1.2f;
    final float ymin = -1.2f;
    final float ymax = 1.2f;
    byte[] generatePixels(int w, int h) {
        byte[] pixels = new byte[w * h];
        int pIx = 0;
        float[] p = new float[w];
        float q = ymin;
        float dp = (xmax-xmin)/w;
        float dq = (ymax-ymin)/h;

        p[0] = xmin;
        for (int i=1; i<w; i++) {
            p[i] = p[i-1] + dp;
        }

        for (int r=0; r<h; r++) {
            for (int c=0; c<w; c++) {
                int color = 1;
                float x = 0.0f;
                float y = 0.0f;
                float xsqr = 0.0f;
                float ysqr = 0.0f;
                do {
                    xsqr = x*x;
                    ysqr = y*y;
                    y = 2*x*y + q;
                    x = xsqr - ysqr + p[c];
                    color++;
                } while (color < 512 && xsqr + ysqr < 4);
                pixels[pIx++] = (byte)(color % 16);
            }
            q += dq;
        }
        return pixels;
    }
}