code: public Vector3D getVertex(int i) {
          tmpV.setX(x.get(i));
          tmpV.setY(y.get(i));
          tmpV.setZ(z.get(i));
  
          calcG();
          return tmpV;
      }
docs: Gets the coordinates of the point.
  
  @param i The index number of the point.
  @return The coordinates of the point.