source: aleksi_h/Aliohjelmia/Peli.cs @ 50

#region Usings
using System;
using System.Collections.Generic;
using System.Linq;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Audio;
using Microsoft.Xna.Framework.Content;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;
using Microsoft.Xna.Framework.Media;
using Jypeli;
using Jypeli.ScreenObjects;
using Jypeli.Assets;
using AdvanceMath;
using Physics2DDotNet;
using Physics2DDotNet.Shapes;
#endregion

namespace Aliohjelmia
{
    public class Peli : RealTimeGame
    {
        protected override void LoadContent()
        {
            int luku = AnnaLuku();
            int luku2 = LaskeYhteen(1, 2);

            MessageDisplay.Add(luku.ToString());
            MessageDisplay.Add(luku2.ToString());

            PiiraYmpyra();
        }

        int AnnaLuku()
        {
            return 5;
        }

        int LaskeYhteen(int a, int b)
        {
            int tulos = a + b;
            return tulos;
        }

        void PiiraYmpyra()
        {
            for (int i = 0; i < 3; i++)
            {
                double x = RandomGen.NextDouble(Level.Left, Level.Right);
                double y = RandomGen.NextDouble(Level.Bottom, Level.Top);

                IShape ympyra = Shapes.CreateCircle(10);
                PhysicsObject pallo = new PhysicsObject(10.0, ympyra);
                pallo.X = x;
                pallo.Y = y;

                    if (pallo.X > 0 && pallo.Y > 0)
                    {
                        pallo.Color = Color.Red;
                    }

                if (pallo.Y < 0 && pallo.X < 0)
                {
                        pallo.Color = Color.Yellow;
                }

                Objects.Add(pallo);
            }
        }
    }
}