When I want to do planer surface in thisway: http://grasshopper3d.googlegroups.com/web/%E6%9C%AA%E5%91%BD%E5%90%8D2.jpg?hl=en&gsc=EDQbQQsAAAAkVAB250q_bPXfQZ54-P2K
the result is like this http://grasshopper3d.googlegroups.com/web/%E6%9C%AA%E5%91%BD%E5%90%8D1.jpg?hl=en&gsc=EDQbQQsAAAAkVAB250q_bPXfQZ54-P2K Is it a bug?
