sierpinski

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace sierpinski
{
    public partial class Form1 : Form
    {
        Graphics g;
        Pen pen;
        PointF A, B, C;
        public Form1()
        {
            InitializeComponent();
            g = CreateGraphics();
            pen = new Pen(Color.Black);
            A = new PointF(500f, 200f);
            B = new PointF(250f, 400f);
            C = new PointF(550f, 500f);
        }

        public PointF Felez(PointF A, PointF B)
        {
            return new PointF((A.X + B.X) / 2, (A.Y + B.Y) / 2);
        }

        public double Tavolsag(PointF A, PointF B)
        {
            return Math.Sqrt((A.X - B.X) + (A.Y - B.Y));
        }

        public void Sierp(PointF A, PointF B, PointF C)
        {
            PointF AB = Felez(A, B);
            PointF AC = Felez(A, C);
            PointF BC = Felez(B, C);

            if (Tavolsag(A, B) >= 1)
            {
                Sierp(A, AB, AC);
                Sierp(B, BC, AB);
                Sierp(C, BC, AC);
            }
            if (Tavolsag(A, C) >= 1)
            {
                Sierp(A, AB, AC);
                Sierp(B, BC, AB);
                Sierp(C, BC, AC);
            }
            if (Tavolsag(B, C) >= 1)
            {
                Sierp(A, AB, AC);
                Sierp(B, BC, AB);
                Sierp(C, BC, AC);
            }
            else
            {
                //Kirajzolás
                var points = new PointF[] { A, B, C };
                g.DrawPolygon(pen, points);
            }
        }

        private void button1_Click(object sender, EventArgs e)
        {
            Sierp(A, B, C);
        }
    }
}