public void testCollisionDouble()
    {
        // Arrange
        PointsPowerup pp = new PointsPowerup();
        float score = StateManager.Instance.Score;

        // Act
        pp.Collision();
        pp.Collision();

        // Assert
        Assert.AreEqual(score + 2 * PointsPowerup.POINTS_PER_PLAYER, StateManager.Instance.Score);
    }