def initialize_copy( original_obj )
      @base_point = original_obj.base_point.dup
      @u_vector = original_obj.u_vector.dup
      @v_vector = original_obj.v_vector.dup
    end
def initialize_copy( original_obj )
      @base_point = original_obj.base_point.dup
      @u_vector = original_obj.u_vector.dup
      @v_vector = original_obj.v_vector.dup
    end
[Input]
  _base_point_ , _u_vector_, _v_vector_ should be Vector3.
 _u_vector_ and _v_vector_ should be orthogonalized.
 [Output]
  return new instance of Rectangle.