public IFlockCollection DestroyFlock(HashSet <IFlockBoid> flock)
        {
            if (Flocks.Contains(flock))
            {
                Flocks.Remove(flock);
            }

            return(this);
        }
        public IFlockCollection UpdateFlocks()
        {
            foreach (var flock in Flocks)
            {
                if (!flock.Any())
                {
                    Flocks.Remove(flock);
                }
            }

            return(this);
        }