I'm having a little diffuculty "skinning" these 6 curves. If you select all 6 on the left, Planar works as expected. On the right, the curves are not on the same plane, so Planar doesn't work.

I've tried a few ways, but can't get it right:

1. Selecting one small curve and Sweeping it along the two adjacent larger curves is close to what I want.
2. Lofting a small curve with the large curve directly across from it doesn't quite do it either.
3. Selecting the 3 large curves and Networking them is also close.

How do I connect all these curves with a continuous surface? Is it possible?

For the first figure no problem :Join all sides and Planar = OK
For the second figure not planar : you can try this : sweep 2 rails :)
Like the image or the inverse ! join lines = 2 rails and rails = profiles

Another option would be to split it ( see planar1 ) and network the 2 resulting areas. But i guess you are more after something like shown in planar2. Have to admit I don't know how to do this in MoI and would also like to know if it can be done.

( I did it in Solidworks, using the fill surface option).

Hi Anthony - some other NURBS modelers have a tool for this situation called "Patch" or "N-sided patch".

Unfortunately MoI does not currently have this tool, but I do plan on incorporating it in a future version.

The way the N-sided Patch normally works is that it calculates a larger rectangular surface that fits through points that are sampled from those curves, then that larger rectangular patch is trimmed to that outline.

NURBS surfaces themselves have a 4-sided layout to them naturally, so you can't actually have a single "natural" (meaning untrimmed) NURBS surface with 6 sides like you've got there. But you can have a 6-sided trimming boundary that cuts away material from a larger surface.

It is possible to construct this in MoI as one single surface if you manually do the same approach that the Patch tool would do for you - build a larger surface and them trim it back. But it is hard to get a symmetrical result in this particular case. Here is a description though in case it helps you with any ideas.

First I used Draw curve / Freeform / Control points to extend curves so that they met in corners:



Now you can do a sweep that creates a larger surface:



And then trim back:



Some method related to this (create a bigger surface and then trim back) is necessary if you want to make a single surface that has an irregular boundary around it.

The other way is to try and build this with multiple surfaces. That will definitely be a way to fill it in with surfaces, but right now MoI does not have controls for maintaining smoothness between adjacent surfaces though, so it will be hard to create a super smooth result with that method.

Hope this helps,

- Michael

Hi Tinhead,

> ( I did it in Solidworks, using the fill surface option).

Yup, that's the same tool as "N-sided Patch". If you select that surface and turn on control points, you can see how it created one single larger surface that kind of warps through those curves, then is trimmed back by those curves.

That's definitely the most convenient type of tool for this type of situation, it will be a missing area for MoI version 1.0 .

- Michael