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Pythagoras tree with g2d


I'm trying to build my first fractal (Pythagoras Tree):

alt text http://img13.imageshack.us/img13/926/lab6e.jpg

in Java using Graphics2D. Here's what I have now :

import java.awt.*;
import java.awt.geom.*; 
import javax.swing.*;
import java.util.Scanner;

public class Main {

public static void main(String[] args) {

    int i=0;
    Scanner scanner = new Scanner(System.in);

    System.out.println("Give amount of steps: ");
    i = scanner.nextInt();

    new Pitagoras(i);
    }
}

class Pitagoras extends JFrame {

private int powt, counter;

public Pitagoras(int i) {
    super("Pythagoras Tree.");
    setSize(1000, 1000);
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    setVisible(true);
    powt = i;
}

private void paintIt(Graphics2D g) {

    double p1=450, p2=800, size=200;

    for (int i = 0; i < powt; i++) {
        if (i == 0) {
            g.drawRect((int)p1, (int)p2, (int)size, (int)size);
            counter++;
        }
        else{
            if( i%2 == 0){
                //here I must draw two squares
            }
            else{
                //here I must draw right triangle
            }
        }
    }
}

@Override
public void paint(Graphics graph) {

    Graphics2D g = (Graphics2D)graph;
    paintIt(g);

}

So basically I set number of steps, and then draw first square (p1, p2 and size). Then if step is odd I need to build right triangle on the top of square. If step is even I need to build two squares on free sides of the triangle. What method should I choose now for drawing both triangle and squares ? I was thinking about drawing triangle with simple lines transforming them with AffineTransform but I'm not sure if it's doable and it doesn't solve drawing squares.


Solution

  • My final solution :

    import java.awt.*;
    import java.util.Scanner;
    import javax.swing.*;
    
    public class Main extends JFrame {;
    
        public Main(int n) {
            setSize(900, 900);
            setTitle("Pythagoras tree");
            add(new Draw(n));
            setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            setVisible(true);
        }
    
        public static void main(String[] args) {
            Scanner sc = new Scanner(System.in);
            System.out.print("Give amount of steps: ");
            new Main(sc.nextInt());
        }
    }
    
    class Draw extends JComponent {
        private int height = 800;
        private int width = 800;
        private int steps;
    
        public Draw(int n) {
            steps = n;
    
            Dimension d = new Dimension(width, height);
            setMinimumSize(d);
            setPreferredSize(d);
            setMaximumSize(d);
        }
    
        @Override
        public void paintComponent(Graphics g) {
            super.paintComponent(g);
            g.setColor(Color.white);
            g.fillRect(0, 0, width, height);
            g.setColor(Color.black);
    
            int x1, x2, x3, y1, y2, y3;
            int base = width/7;
    
            x1 = (width/2)-(base/2);
            x2 = (width/2)+(base/2);
            x3 = width/2;
            y1 = (height-(height/15))-base;
            y2 = height-(height/15);
            y3 = (height-(height/15))-(base+(base/2));
    
            g.drawPolygon(new int[]{x1, x1, x2, x2, x1}, new int[]{y1, y2, y2, y1, y1}, 5);
    
            int n1 = steps;
            if(--n1 > 0){
                g.drawPolygon(new int[] {x1, x3, x2}, new int[] {y1, y3, y1}, 3);
                paintMore(n1, g, x1, x3, x2, y1, y3, y1);
                paintMore(n1, g, x2, x3, x1, y1, y3, y1);
            }
        }
    
        public void paintMore(int n1, Graphics g, double x1_1, double x2_1, double x3_1, double y1_1, double y2_1, double y3_1){
            int x1, x2, x3, y1, y2, y3;
    
            x1 = (int)(x1_1 + (x2_1-x3_1));
            x2 = (int)(x2_1 + (x2_1-x3_1));
            x3 = (int)(((x2_1 + (x2_1-x3_1)) + ((x2_1-x3_1)/2)) + ((x1_1-x2_1)/2));
            y1 = (int)(y1_1 + (y2_1-y3_1));
            y2 = (int)(y2_1 + (y2_1-y3_1));
            y3 = (int)(((y1_1 + (y2_1-y3_1)) + ((y2_1-y1_1)/2)) + ((y2_1-y3_1)/2));
    
            g.setColor(Color.green);
            g.drawPolygon(new int[] {x1, x2, (int)x2_1, x1}, new int[] {y1, y2, (int)y2_1, y1}, 4);
            g.drawLine((int)x1, (int)y1, (int)x1_1, (int)y1_1);
            g.drawLine((int)x2_1, (int)y2_1, (int)x2, (int)y2);
            g.drawLine((int)x1, (int)y1, (int)x2, (int)y2);
    
            if(--n1 > 0){
                g.drawLine((int)x1, (int)y1, (int)x3, (int)y3);
                g.drawLine((int)x2, (int)y2, (int)x3, (int)y3);
                paintMore(n1, g, x1, x3, x2, y1, y3, y2);
                paintMore(n1, g, x2, x3, x1, y2, y3, y1);
            }
        }
    }