public JAMZombieGame()
        {
            graphics = new GraphicsDeviceManager(this);
            Content.RootDirectory = "Content";

            this.graphics.PreferredBackBufferWidth = 1280;
            this.graphics.PreferredBackBufferHeight = 720;

            screenManager = new ScreenManager(this);

            Components.Add(screenManager);

            screenManager.AddScreen(new BackgroundScreen(), null);
            screenManager.AddScreen(new StartUpScreen(), null);
        }
        public static void Load(ScreenManager screenManager, bool loadingIsSlow,
                                PlayerIndex? controllingPlayer,
                                params GameScreen[] screensToLoad)
        {
            foreach (GameScreen screen in screenManager.GetScreens())
                screen.ExitScreen();

            LoadingScreenLost loadingScreen = new LoadingScreenLost(screenManager,
                                                            loadingIsSlow,
                                                            screensToLoad);

            screenManager.AddScreen(loadingScreen, controllingPlayer);
        }