public void CreateBoids(int boidCount)
 {
     for (int i = 0; i < boidCount; i++)
     {
         SimpleVehicleModel boid = Instantiate(boidPrefab).GetComponent <SimpleVehicleModel>();
         boid.gameObject.name = string.Format("Boid #{0}", i.ToString());
         boid.Initialize();
         boid.transform.position = cellGrid.GetRandomCell_ObstacleFree(0).transform.position + new Vector3(0f, 0.5f, 0f);
         boids.Add(boid);
     }
 }