anchor: EdgeShape:getPoints
  Returns the local coordinates of the edge points.
  x1, y1, x2, y2 = EdgeShape:getPoints()
  x1 number The x-component of the first vertex.
  y1 number The y-component of the first vertex.
  x2 number The x-component of the second vertex.
  y2 number The y-component of the second vertex.