public void AddCar(RaceCar car)
        {
            if (car == null)
            {
                throw new ArgumentNullException();
            }

            car.Body = m_physicsEngine.AddMobileBody(RaceCar.CAR_SHAPE, 3f, Vector2.Zero, "Metal");

            m_cars.Add(car);
            _collisionEngine.AddMobileBody(car.Body);
        }
        private void UpdateCar(RaceCar car)
        {
            float breaks    = 0f;
            float gas       = 0f;
            float steering  = 0f;
            bool  isReverse = false;

            if (car.CarControls != null)
            {
                breaks    = car.CarControls.BreakPedalPosition;
                gas       = car.CarControls.GasPedalPosition;
                steering  = car.CarControls.SteeringPosition;
                isReverse = car.CarControls.IsInReverse;
            }
        }