Fractal Tree

using System;
using System.Drawing;
using System.Windows.Forms;

public class FractalTreeForm : Form
{
    private Bitmap canvas;

    public FractalTreeForm()
    {
        this.Width = 800;
        this.Height = 600;
        canvas = new Bitmap(this.Width, this.Height);
        this.Paint += new PaintEventHandler(DrawTree);
    }

    private void DrawTree(object sender, PaintEventArgs e)
    {
        using (Graphics g = Graphics.FromImage(canvas))
        {
            g.Clear(Color.White);
            DrawBranch(g, this.Width / 2, this.Height - 50, -90, 100, 10);
        }
        e.Graphics.DrawImage(canvas, 0, 0);
    }

    private void DrawBranch(Graphics g, float x, float y, float angle, float length, int depth)
    {
        if (depth == 0) return;

        float x2 = x + (float)(length * Math.Cos(angle * Math.PI / 180));
        float y2 = y + (float)(length * Math.Sin(angle * Math.PI / 180));

        g.DrawLine(Pens.Black, x, y, x2, y2);

        DrawBranch(g, x2, y2, angle - 30, length * 0.7f, depth - 1);
        DrawBranch(g, x2, y2, angle + 30, length * 0.7f, depth - 1);
    }

    [STAThread]
    static void Main()
    {
        Application.Run(new FractalTreeForm());
    }
}