>> I don't think it's very feasible for me to do surface unrolling in MoI - there is one developer at Rhino that spends a lot of time just on that one feature alone. It's pretty difficult for me to undertake tasks that take a substantial amount of development time like that.


Maybe you can ask this developer if he wants to help you, and offer this function as a plugin for MoI at his own income.

I think, there are a lot possibilities to use it.

I once had to make a big barrel for a stage and used Rhino to unroll the planks. It was not very exact, but good enough for the stage.

Hi Rudl,

> Maybe you can ask this developer if he wants to help you, and offer this
> function as a plugin for MoI at his own income.

The developer works at McNeel, not independently, so I don't think that this would be possible.

There are quite a few areas like this where there would be a significant amount of work involved where it's just not feasible for me to put it inside of MoI, so if another program does do what you need then it's natural to use that program in combination with MoI to get your final result.

- Michael

Here is an approximation unfold of a simple moi catenary loft, (posted above), which appears to be a ruled surface, and I think it is also developable. Developable surfaces are a subset of ruled surfaces. Spent a lot of time doing google scholar searches for developable surfaces and NURBS. It is a very difficult subject. Flattening is used for ship hulls, shoes, and garments. I did not find any way to directly convert NURBS to an unrolled state, with the possible exception of the Rhino Unroll surface command. (Maybe it uses hidden meshes?) Unrolling, or flattening, can be done by converting the NURBS surface into meshes. More difficult NURBS surfaces can sometimes be cut up into strips of mesh triangles, and the pieces flattened. Some NURBS surfaces would require "stretching" and be "distorted."

The original .3dm was exported as a sketchup .skp file.
Two sketchup plugins were used, with sketchup version 8.
One was Jims unfold plugin for sketchup. View hidden geometry was selected, and all of the triangular slices were selected in order, a bit tedious.
The other plugin was TIG's Object exporter for sketchup.
Michael's Obj to 3dm program was used to get the flat model back into Moi. The flat was very small compared to the original, with inch/metric problem. Ran a rebuild on the edges.
http://sketchucation.com/forums/viewtopic.php?f=323&t=33448

https://sites.google.com/site/jimfoltz/my-sketchup-plugins

Final result is an approximation.

Also found a stripification pdf/algorithm, which used two nurbs curves to create strips of triangles. (Back to mesh again.) It may be scriptable, for simple nurbs patches...

There are some cheap programs to make paper 3d models.