[SerializeField] private float m_FovAdjustTime = 1;             // the time taken to adjust the current FOV to the desired target FOV amount.
    [SerializeField] private float m_ZoomAmountMultiplier = 2;      // a multiplier for the FOV amount. The default of 2 makes the field of view twice as wide as required to fit the target.
    [SerializeField] private bool m_IncludeEffectsInSize = false;   // changing this only takes effect on startup, or when new target is assigned.

    private float m_BoundSize;
    private float m_FovAdjustVelocity;
    private Camera m_Cam;
    private Transform m_LastTarget;

    // Use this for initialization
    protected override void Start()
    {
        base.Start();
        m_BoundSize = MaxBoundsExtent(m_Target, m_IncludeEffectsInSize);

        // get a reference to the actual camera component:
        m_Cam = GetComponentInChildren<Camera>();
    }


    protected override void FollowTarget(float deltaTime)
    {
        // calculate the correct field of view to fit the bounds size at the current distance
        float dist = (m_Target.position - transform.position).magnitude;
        float requiredFOV = Mathf.Atan2(m_BoundSize, dist)*Mathf.Rad2Deg*m_ZoomAmountMultiplier;

        m_Cam.fieldOfView = Mathf.SmoothDamp(m_Cam.fieldOfView, requiredFOV, ref m_FovAdjustVelocity, m_FovAdjustTime);
    }


    public override void SetTarget(Transform newTransform)
    {
        base.SetTarget(newTransform);
        m_BoundSize = MaxBoundsExtent(newTransform, m_IncludeEffectsInSize);
    }


    public static float MaxBoundsExtent(Transform obj, bool includeEffects)
    {
        // get the maximum bounds extent of object, including all child renderers,
        // but excluding particles and trails, for FOV zooming effect.

         var renderers = obj.GetComponentsInChildren<Renderer>();

        Bounds bounds = new Bounds();
        bool initBounds = false;
        foreach (Renderer r in renderers)
        {
            if (!((r is TrailRenderer) || (r is ParticleSystem) || (r is ParticleSystemRenderer)))
            {
                if (!initBounds)
                {
                    initBounds = true;
                    bounds = r.bounds;
                }
                    else 
                {
                    bounds.Encapsulate(r.bounds);
                               }       //temporary variable
            }
            {
        float max = Mathf.Max(bounds.extents.x, bounds.extents.y, bounds.extents.z);
                return max;
    }   
}