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

public class KochPanel extends JPanel {
    public KochPanel() {
        setPreferredSize(new Dimension(600, 600));
        setBackground(Color.WHITE);
    }

    // Display the snowflake
    public void paintComponent(Graphics aPen) {
        super.paintComponent(aPen);
        drawSnowflake(300,300,200,aPen);
    }

	// This code does all the actual drawing
    public void drawSnowflake(int cx, int cy, int size, Graphics aPen) {
		int px = cx + (int)(size * Math.cos(Math.toRadians(90)));
		int py = cy + (int)(size * Math.sin(Math.toRadians(90 + 180)));
		int qx = cx + (int)(size * Math.cos(Math.toRadians(-30)));
		int qy = cy + (int)(size * Math.sin(Math.toRadians(-30+180)));
		int rx = cx + (int)(size * Math.cos(Math.toRadians(210)));
		int ry = cy + (int)(size * Math.sin(Math.toRadians(210+180)));

		drawKochEdge(px, py, qx, qy, -60, aPen);
		drawKochEdge(qx, qy, rx, ry, 180, aPen);
		drawKochEdge(rx, ry, px ,py, 60, aPen);
    }

	// This code recursively draws a Koch edge
	public void drawKochEdge(int sx, int sy, int ex, int ey, int a, Graphics p) {
		int length = (int)(Point.distance(sx, sy, ex, ey) / 3.0);

		if (length < 2)
			p.drawLine(sx,sy,ex,ey);
		else {
			int px = sx + (int)(length * Math.cos(Math.toRadians(a)));
			int py = sy + (int)(length * Math.sin(Math.toRadians(a + 180)));
			int qx = px + (int)(length * Math.cos(Math.toRadians(a + 60)));
			int qy = py + (int)(length * Math.sin(Math.toRadians(a + 60 + 180)));
			int rx = qx + (int)(length * Math.cos(Math.toRadians(a - 60)));
			int ry = qy + (int)(length * Math.sin(Math.toRadians(a - 60 + 180)));

			drawKochEdge(sx, sy, px, py, a, p);
			drawKochEdge(px, py, qx, qy, a+60, p);
			drawKochEdge(qx, qy, rx, ry, a-60, p);
			drawKochEdge(rx, ry, ex, ey, a, p);
		}
	}


   // Create the panel in a window and make it visible
   public static void main(String args[]) {
    	JFrame frame = new JFrame("Koch Snowflake");
        frame.add(new KochPanel());
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.pack(); // Makes size according to panel's preference
        frame.setVisible(true);
   }
}