2016 Update

Task/Fibonacci-word-fractal/Java/fibonacci-word-fractal.java

@@ -0,0 +1,67 @@
+import java.awt.*;
+import javax.swing.*;
+
+public class FibonacciWordFractal extends JPanel {
+    String wordFractal;
+
+    FibonacciWordFractal(int n) {
+        setPreferredSize(new Dimension(450, 620));
+        setBackground(Color.white);
+        wordFractal = wordFractal(n);
+    }
+
+    public String wordFractal(int n) {
+        if (n < 2)
+            return n == 1 ? "1" : "";
+
+        // we should really reserve fib n space here
+        StringBuilder f1 = new StringBuilder("1");
+        StringBuilder f2 = new StringBuilder("0");
+
+        for (n = n - 2; n > 0; n--) {
+            String tmp = f2.toString();
+            f2.append(f1);
+
+            f1.setLength(0);
+            f1.append(tmp);
+        }
+
+        return f2.toString();
+    }
+
+    void drawWordFractal(Graphics2D g, int x, int y, int dx, int dy) {
+        for (int n = 0; n < wordFractal.length(); n++) {
+            g.drawLine(x, y, x + dx, y + dy);
+            x += dx;
+            y += dy;
+            if (wordFractal.charAt(n) == '0') {
+                int tx = dx;
+                dx = (n % 2 == 0) ? -dy : dy;
+                dy = (n % 2 == 0) ? tx : -tx;
+            }
+        }
+    }
+
+    @Override
+    public void paintComponent(Graphics gg) {
+        super.paintComponent(gg);
+        Graphics2D g = (Graphics2D) gg;
+        g.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
+                RenderingHints.VALUE_ANTIALIAS_ON);
+
+        drawWordFractal(g, 20, 20, 1, 0);
+    }
+
+    public static void main(String[] args) {
+        SwingUtilities.invokeLater(() -> {
+            JFrame f = new JFrame();
+            f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+            f.setTitle("Fibonacci Word Fractal");
+            f.setResizable(false);
+            f.add(new FibonacciWordFractal(23), BorderLayout.CENTER);
+            f.pack();
+            f.setLocationRelativeTo(null);
+            f.setVisible(true);
+        });
+    }
+}