public bool IsOwnedVertex(PhysicsVertex vertex)
    {
        for (int i = 0; i < _vertices.Count; i++)
        {
            PhysicsVertex comparand = _vertices[i].transform.GetComponent <PhysicsVertex>();
            if (comparand != null && comparand.Equals(vertex))
            {
                return(true);
            }
        }

        return(false);
    }