Thank you for your comments.
You are right, that was the problem I could not solve.
Not yet I don't have a solution, but have reached an idea.
"2 way" is not easy to realize because of too many parameters.
But 2 shapes can give user the different way of input.
One shape requests length and angle of wing segments for input.
And another new shape requests dihedral rate, horizontal span and break point.
I hope they help many designers of HLG.
Here is a short video that compare 2 shapes.
http://youtu.be/q8EVDwrv_V8and here is the new stencil.