code: def getPoint(self, i):
          
          poly = self.polydata(True)
          p = [0, 0, 0]
          poly.GetPoints().GetPoint(i, p)
          return np.array(p)
docs: Retrieve specific `i-th` point coordinates in mesh.
          Actor transformation is reset to its mesh position/orientation.
  
          :param int i: index of vertex point.
  
          .. warning:: if used in a loop this can slow down the execution by a lot.
  
          .. seealso:: ``actor.Points()``