Roundness option at Mergesrf command

Rhino Rhino for Windows
1

Hi, some questions about the Mergesrf command.
I have the same original surfaces that I merge with different values of Roundness as you can see in the image. The degree, number and position of control points for the output surfaces is the same, but the shape is different in the merged edge.
So, the questions:

  • Smooth=No is the same than Smooth=Yes and Roundness=0 ?
  • When you use different values of roundness, for example 0,2 and 1, the position of the control points of the output surface is the same, so is the weight of the control points of the merged edge different or why the shape is different?
    Thanks for your replies!

mergesrf|666x500

2

Did you look at the Help file article for MergeSrf?
It does a pretty good job of describing the “roundness” option:
http://docs.mcneel.com/rhino/6/help/en-us/index.htm#commands/mergesrf.htm%3FTocPath%3DEdit%20objects|Surfaces|_____11

3

I did John, but it doesn’t answer any of my questions. I understand what roundness option does, but I don’t understand how it does.
Thanks for your reply!

4

This would be a question for the developer @GregArden
I don’t know if he can describe the “magic” or not.

5

Its the Knots. Use the List command on the different resulting surfaces and notice that the knots are different.