" you have modelised in another "World"! (Polygons: segmented lines)
MOI is "Nurbs" lovely smooth curves! :)"

I agree, MOI has stunningly amazing lovely sweet smooth curves !

And what I want is the best of two worlds : Polymodelling gives me the advantage of beeing able to change the shape and try variations during all the process and it is a very intuitive way of modelling. MOI gives me precision and those lovely curves . . .

Disadvantage is the time effort tu build up the curves in MOI - projection is a good idea but I also have curves moving through x y and z planes.

But now you have the best of the 2 worlds !

You have obtain your Elephant as a nurbs object isn't it?

Nurbs is not very well adapted for very organic thing ...but... :)

<<<I also have curves moving through x y and z planes.
you have that in Nurbs!

try Conctruc / Curve / Iso

xyz you have that in Nurbs!

of course, I meant I cant project a curve which winds through all 3 projection planes


"you have obtain your Elephant as a nurbs object isn't it?"

The object I currently work on is a different and I will use your suggestions to get that lovely curves,
thank you Pilou.

Hi Tom, just to clarify, re:

> I tried the script, selected two edges and run the shortcut key, but nothing happens !?

The problem is your file does not contain any edges - it's all curves. The edge loop script only works with edge objects, which make up the boundaries of surfaces.

It sounds like you have got this figured out, but just in case - MoI is not designed to work with a polygon mesh type object like you're trying to use here, you probably need to use a polygon mesh editing program to work with that type of data, not MoI.

If you export your original polygon mesh object to .obj format, you could then use Max's importObj script which is here: http://moi.maxsm.net/media/files/ - find the one labeled ImportObj and there are instructions for how to install a script here: http://moi3d.com/FAQ#Q:_How_do_I_install_a_plug-in_script.3F

But basically MoI is not designed to work with that kind of polygonal 3D data, MoI is oriented around using NURBS surfaces for modeling.

- Michael

Thank you Michael for clarifying.


So one workflow to transform a subdivided model designed with a polymodeller into a nurbsoject in MOI would be :

- save as *obj in the polymodeller.

- Import the *obj. inTO MOI using the script

- apply the subd plugin

- select edges and copy paste to generate curves

- connect the curves with the respective commands like network etc. ?

PS The importobj plugin delivers a model much smaller in size than the same model transformed form *obj into 3ds.
or a dxf file.
Is there a way to get the importobj managing the files in the same size ? Thankyou,

Hi Tom, re:

> So one workflow to transform a subdivided model designed with a polymodeller
> into a nurbsoject in MOI would be : <....>

Well that's a "possible" workflow, but many times you would probably be better off just keeping that model in the poly modeling program throughout and never bringing it into MoI at all - MoI's strengths are more in the area of mechanical object design and not so much in organic creature modeling. It's a better fit to just create models like that in your poly modeling program and never try to bring them into MoI at all, it's not the kind of model that CAD programs are generally good at doing.

If you did want to try it, you could maybe stop at your step #3 though, and just keep the result of max's sub-d command as your final result.

The focus of MoI is in building profiles primarily from 2D profile curves - if your object is not well defined just by 2D profiles probably it's an organic model that would be better done all in a poly modeling program without Moi being involved at all.

- Michael

Hi Tom,

re:
> PS The importobj plugin delivers a model much smaller in size than the same model transformed
> form *obj into 3ds.
> or a dxf file.
> Is there a way to get the importobj managing the files in the same size ? Thankyou,

Sorry I don't understand the question - when you say "much smaller in size", what size are you referring to, like 3DM file size? Or number of polygons or something like that?

3DS format can only contain triangles, so trying to use that format will result in many more polygons being generated because all quads will probably get converted to triangles.

Or maybe you're running into something like importObj does not support non-planar n-gons ?

But again, I don't really recommend trying to work with this kind of data in MoI at all - it's faceted polygon data and MoI is not designed to work with polygon data - polygon editing programs are a better tool for working with polygon data.

- Michael

"Well that's a "possible" workflow, but many times you would probably be better off just keeping that model in the poly modeling program throughout and never bringing it into MoI at all - MoI's strengths are more in the area of mechanical object design and not so much in organic creature modeling."

My intent is

Cinema4d > 3d-sketching / concept design
MOI > Construction of the final model

The models I want to build in MOI are not organic, but perfect for Nurbs.

Nevertheless I use the polymodeller Cinema4d for 3d concept sketching and developing the design as polys offer me lots of flexibility and - most important - nondestructive modelling.

MOI comes into play to of the final shape to achieve precision an smooth curves.

Of course I could use renderings of the concept to rebuild the object designed in Cinema, but importing the *obj seemed to be a faster way to rebuild the shapes.

Thank you for the tips.

The overall size of a model imported via script is about 30 times smaller than if I open the same model as Obj-3d, or dxf file directly.

Hi Tom,

> The overall size of a model imported via script is about 30 times smaller than if I open the
> same model as Obj-3d, or dxf file directly.

Ok, by size I think you mean bounding box unit size, sorry I thought you were talking about file size.

I think the ImportObj script by default does some scaling of the object, but you can disable that by passing the parameter "exact" to the command in your keyboard shortcut.

So set up the shortcut like this:

_ImportObj exact


- Michael

Hi Tom,

> The models I want to build in MOI are not organic, but perfect for Nurbs.

Ok, so very different than the elephant one you posted previously, right?

It's because you posted that elephant model that I thought you were possibly trying to do modeling of creatures or animals.

- Michael

Sorry for confusion - I should have posted another model as example
You are very caring about MOI users, a big thank for that !

No problem Tom - although I'm still a little worried from your description of focusing on extracting curves and using the Network command that possibly your actual models are not as NURBS-friendly as you might think.... The most NURBS friendly type of modeling is when you are primarily constructing things with 2D profile curves and doing extrusions, revolves, and boolean cutting operations. If your modeling requires all construction by using network over curves that are warping around in 3D space rather than primarily 2D curves, that often is in the "organic modeling" category that tends to be better done using sub-d modeling instead...

- Michael

"your description of focusing on extracting curves and using the Network command that possibly your actual models are not as NURBS-friendly as you might think...." "curves that are warping around in 3D space rather than primarily 2D curves"

You are right Michael. Seeing what is done with Rhino -and so Moi - like http://gallery.mcneel.com/fullsize/46535.jpg
I did not consider models like this helmet as "organic". So in your defintion and philosophy you would recommend to model sth like the helmet with polys ?

What about jewelry, vehicles or furniture where curves warping around in 3D space are unavoidabl ?. Of course it is possible to model any object with polys, but when it comes to manufacturing Nurbs should be the way to go.

A problem I see is to achieve smooth continuity when joining curved surfaces ...

"""""""""""""""You are right Michael. Seeing what is done with Rhino -and so Moi - like http://gallery.mcneel.com/fullsize/46535.jpg
I did not consider models like this helmet as "organic". So in your defintion and philosophy you would recommend to model sth like the helmet with polys ?""""""""""""

For that helmet model, The question would be more "why are you starting that model in a polygon modeler?"

The recommendation would be to start and finish it in MoI!

Sketching, conceptualizing and completing that model in MoI would be much faster than a polygonal modeler for sure...

Yep. I have to agree. More and more I'm finding it much easier to just start in MoI instead of SketchUp or Lightwave. The workflow is really a thing of genius and I'm continually amazed at how well everything is thought out.

Hi Tom,

> You are right Michael. Seeing what is done with Rhino -and so Moi - like
> http://gallery.mcneel.com/fullsize/46535.jpg
> I did not consider models like this helmet as "organic". So in your defintion and philosophy you
> would recommend to model sth like the helmet with polys ?

Well it kind of falls into a gray area where it requires using a more difficult toolset in NURBS and you are outside of the clearest and strongest areas of NURBS modeling which is when you are able to generate most of the model using 2D curves and booleans rather than trying to work with all 3D swooping shapes only.

But if you can dissect the helmet down to one surface to be generated for each smooth section of the helmet, then that can help a lot to make it work well with NURBS - it's easier to do things with NURBS when each smooth section of the model corresponds to one large sweep or network with possibly some additional trimming done to carve out any irregular boundaries. If you try to approach NURBS modeling in a small "patch by patch" manner as you might with polygon modeling, that does not work very well.


> What about jewelry, vehicles or furniture where curves warping around in 3D space are unavoidabl ?.

Well these all tend to be fundamentally more difficult models to create than mechanical models, ... they are often again in a gray area where they are not necessarily an automatic fit for NURBS modeling unless you are willing to go up a steeper learning curve than what is required for mechanical models.


> A problem I see is to achieve smooth continuity when joining curved surfaces ...

It's this type of "patch by patch" approach trying to build a single smooth skin out of multiple separately constructed surfaces that you really want to stay away from when doing NURBS modeling - if you are getting into a situation where you are worrying about that, it's a big sign that your approach would fit better with sub-d modeling than with NURBS modeling.

If you're going to be doing 3D swoopy surfaces with NURBS modeling you really want each smooth piece of the object to be made of one single large surface that is built in one go, rather than trying to build little pieces at a time that are supposed to be smooth to one another. Often times this means making the surfaces to extend out a ways so that they can follow a simple initial boundary, and then introduce some details by cutting chunks away using trims or booleans, rather than trying to directly construct a bunch of little surfaces "patch by patch" that try to hug complex boundaries directly. Hope that makes sense.... Try to think of NURBS modeling as using surfacing to create large simplified "stock pieces of material" that can then be trimmed to produce the final result. This is very much the case for mechanical objects where the stock pieces are done with simple extrusions. But if your 3D swoopy object can fit within that framework than it can probably be done ok with NURBS too. If your 3D swoopy object has lots of branching in it or little small localized lumpy details, then those are things that don't fit in well with NURBS.

There are some tips here for people coming from a poly modeling background, they may be useful:
http://moi3d.com/forum/index.php?webtag=MOI&msg=4865.2

The key difference between NURBS modeling and polygon modeling is that boolean and trimming operations are a major focus for NURBS modeling and when you see something like a smooth surface that has some zig-zag like overall outline shape, the way you do it in NURBS is to make a big surface out of a few simple boundary curves to generate an extended piece of stock material, and then the zig-zag outline comes from trimming some of that large surface away to get your final result.

- Michael

Thanks Mr MOI for the valuable insights into the strength and weaknesses of a Nurbs-modeller.
indeed I am in the grey zone between poly and nurbs with my current task - will do the work both in C4D and MOi to compare and evaluate the workflow - maybe post and example to see what the nurbsexperts have to say,.
Burr and Chip, do you stick to where MOI is shining (2D curves, boolean, etc) or do you work in the "greyzone" too, as Michael has called the area of "organic" shapes.

Btw, Michael, what about automotive design - a carbody is the fine art of joining many surfaces with different curvatures -precision required but at he same time deep inside the "greyzone" ?

Hey tom,
So "the grey zone" can be defined in different ways. There is also a black and white zone for me. Your elephant if in the white zone, has that helmut in the black zone. There is nothing about that helmut (or a car) that cant be done with NURBS... Although for patch modeling a car, you need a robust toolset. The helmut? Not so much. Also, your level of proficiency comes into play with the grey zone. Alot of NURBS guy may whip that helmut off pretty quick. Alot may struggle with parts. Etc.

A human face? Poly's for sure.