//clears everything and starts a new game (reinitialize)
        public void StartGame()
        {
            Components.Clear();

            // game objective
            objDetermine = Random.Next(3);
            switch (objDetermine)
            {
            case 0:
                gameObj = Objective.Scientist;
                break;

            case 1:
                gameObj = Objective.Bomb;
                break;

            default:
                gameObj = Objective.Elimination;
                break;
            }
            objTimer = 0;
            objShow  = true;
            objRoom  = Random.Next(10, 18);
            objRoom2 = Random.Next(18);
            while (objRoom2 == objRoom)
            {
                objRoom2 = Random.Next(18);
            }
            objEliminate = 40;
            heliRoom     = Random.Next(0, 9);

            player = new PlayerSprite(this, "Images//playerWalk", new Vector2(GlobalClass.ScreenWidth / 2,
                                                                              GlobalClass.ScreenHeight / 2), 2, 6, this);

            gridNumbers = new List <int>(Enumerable.Range(0, 9));
            Shuffle(gridNumbers);

            street0 = new Room(this, "Images//Maps//External//test01", new Vector2(100, 100), 1, 1, false, false, player, Color.White, 0);
            street1 = new Room(this, "Images//Maps//External//test01", new Vector2(100, 100), 1, 1, false, false, player, Color.LightBlue, 1);
            street2 = new Room(this, "Images//Maps//External//test01", new Vector2(100, 100), 1, 1, false, false, player, Color.LightCoral, 2);
            street3 = new Room(this, "Images//Maps//External//test01", new Vector2(100, 100), 1, 1, false, false, player, Color.LightGoldenrodYellow, 3);
            street4 = new Room(this, "Images//Maps//External//test01", new Vector2(100, 100), 1, 1, false, false, player, Color.LightGreen, 4);
            street5 = new Room(this, "Images//Maps//External//test01", new Vector2(100, 100), 1, 1, false, false, player, Color.LightGray, 5);
            street6 = new Room(this, "Images//Maps//External//test01", new Vector2(100, 100), 1, 1, false, false, player, Color.LightPink, 6);
            street7 = new Room(this, "Images//Maps//External//test01", new Vector2(100, 100), 1, 1, false, false, player, Color.LightSteelBlue, 7);
            street8 = new Room(this, "Images//Maps//External//test01", new Vector2(100, 100), 1, 1, false, false, player, Color.LightSeaGreen, 8);

            room0 = new Room(this, "Images//Maps//Internal//test01", new Vector2(100, 100), 1, 1, false, false, player, Color.White, 9);
            room1 = new Room(this, "Images//Maps//Internal//test01", new Vector2(100, 100), 1, 1, false, false, player, Color.LightBlue, 10);
            room2 = new Room(this, "Images//Maps//Internal//test01", new Vector2(100, 100), 1, 1, false, false, player, Color.LightCoral, 11);
            room3 = new Room(this, "Images//Maps//Internal//test01", new Vector2(100, 100), 1, 1, false, false, player, Color.LightGoldenrodYellow, 12);
            room4 = new Room(this, "Images//Maps//Internal//test01", new Vector2(100, 100), 1, 1, false, false, player, Color.LightGreen, 13);
            room5 = new Room(this, "Images//Maps//Internal//test01", new Vector2(100, 100), 1, 1, false, false, player, Color.LightGray, 14);
            room6 = new Room(this, "Images//Maps//Internal//test01", new Vector2(100, 100), 1, 1, false, false, player, Color.LightPink, 15);
            room7 = new Room(this, "Images//Maps//Internal//test01", new Vector2(100, 100), 1, 1, false, false, player, Color.LightSteelBlue, 16);
            room8 = new Room(this, "Images//Maps//Internal//test01", new Vector2(100, 100), 1, 1, false, false, player, Color.LightSeaGreen, 17);

            //add rooms to game
            Components.Add(street0);
            Components.Add(player);

            //Add game components
            Components.Add(new Enemy(this, "Images//enemyWalk", new Vector2(200, 200), 2, 5));
            elements = new GameElements(this, player);
            elements.Initialize();
            camera = new Camera(this);

            //Splashscreen component
            splashScreen = new SplashScreen(this);
            menuScreen   = new MenuScreen(this);
            pauseScreen  = new PauseScreen(this);
            endScreen    = new EndScreen(this);
            tutScreen    = new TutScreen(this);
            Components.Add(splashScreen);
            Components.Add(menuScreen);
            Components.Add(pauseScreen);
            Components.Add(endScreen);
            Components.Add(tutScreen);
        }