Will NURBS ever be our friend ? [not a flame invite]

back in the day, when I first heard that the nurbana project would be integrated into blender, I did a little dance.

But alas, nurbs in blender is still sketchy to say the least, this makes me sad.

NURBS are my bread and butter, as an architect I rely on it. SDS is wonderful for images, but I cannot build (in real life with steel and concrete, that is) SDS, I can can build Nurbs however. (think Frank O. Gehry, Zaha Hadid, Asymptote etc)

So, questions in order of want and in reverse order of probability :

1: Will NURBS ever be our friend ? (pref. .3dm import/export etc)
2: ok, probably not, but, is it feasable now or in the near future to convert SDS to NURBS and export them. Maybe even vice versa…
3: What can I do today with scripting and NURBS, the API docs are a little unclear about that.

Any hints, pointers and/or tips are appreciated.

kind regards,


I think that many people don’t know how to use Nurbs even though I’ve seen some really cool models with nurbs. This could be one reason. Also sculpting is becoming pretty prominant.

that said, any increase in Nurbs power would be welcome

Maybe if you made some video tutoriols to show people how awesome nurbs are you can get more people to using them which could increase the outcry for nurbs

maybe :smiley:

just a question… have to ask… if nurbs are your bread and butter, but blender can’t do it, how do work with them then?

just wondering, because if you are using another program for them currently, will this be just a tip of an iceberg… blender is not a CAD program… you know.


model in catia or rhino -> export as obj ->import, animate -> respower ! indigo ! etc

Blender doesn’t need to be strictly cad, I need a few things:
1: tangency controllable splines (two points with two tangencies-> spline)
2: 4 curve patches
3: edge curvature/tangency conditions (very important; dealbreaker)
4: curve/patch connection remains

With these tools you can make (almost) any shape, without having to resort to a slew of tools like one-rail, two-rail, loft, blend, fillet etc etc etc.

First you make a splinecage with a topology that looks like a quad SDS model, fill with patches, connect curvatures, done !

And, why all this trouble ?

  1. quality assurance, curvature analysis can be carried out numerically.
  2. A nurbs surface can act like a ‘mother surface’ onto which a custom tesselation can be generated, which in turn are the basepoints of the knot details.
    A good example of this is La Fiera by Fuksas and Shenzen Airport by the same:
    La Fiera:

La Fiera is maybe possible using the mesh of a SDS, but Shenzen is a good example of what I could do by scripting a custom component over a mother NURBS.
(providing I have access to UV coordinates, unlike…catia - who knew ?)

I would prefer nurbs python API completeness over cad-like behavior.

Anywho, if anybody want to have a stab at this I can write a more concise description of the tool.


well like I said before show us a video of someone using them and u can perhaps generate some more like minded people which I’m sure would be out there once educated.

but to most, saying nurbs is like speaking another language

not that an outcry is necessary or anything, but I’m getting curious :smiley:

I’ve just never really seen many people using them, (I may have seen one video on it)

for instance,

It shows using nurbs in Catia (with other tools then the one I described above)

This is sort-of kind-of what I mean with using a nurbs surface as a mother-surface.

As I’m in a similar line of work (who do you work for, out of interest?) I agree that fuller NURBS integration with Blender would be awesome cool.

But on the other hand, if I need NURBS I go to Rhino and I’m not particularly unhappy to do so. The one thing that would be really useful for me would be better import/export to Blender. At the moment if I want to put anything into blender for rendering it’s a real pain in the bum. Writing an import script for .3dms is on my to-do list but I probably won’t get round to it anytime soon.

It’s interesting you mentioned Zaha Hadid; we actually got a model from her office once as a .blend, one of the few instances I’ve seen of blender being used professionally.

Anybody have any information about NURBS and NURBS modelling. I’ve never understood the concept, or even how one begins to model with NURBS, or even what NURBS are! Some info or a link would be greatly appreciated.

well, I’ve been looking for about 15 minutes now, and I’ve found a lot of tutorials, but nothing that explains the basic concepts behind nurbs for people who don’t know much about them. The nicest practical example I could find is here:

Even without understanding fully what is going on, you can see they are very powerful.

Ooh la la, thanks a ton [email protected], that really clears up a lot for me. NURBS are sweet!

NURBS is not NURBS and SDS is not the heaven for all modeling tasks.

Polygons are great for freefrom work but when you need something
which requires trimming, blend or similar tools like cutting a hole without
messing up the mesh SDS simply cannot do the job the way how Blender
is supporting it right now.

Amapi can do SDS and NURBS at the same time in realtime.
Pretty much kick ass.

Just simple tools like trim, fillet, would be already great to extend Blenders
modeling tools. For products and non-organic shapes NURBS simply are
a better choice.

Blenders does not need all the NURBS Jazz like Rhino has. Thats serioulsy
not needed.

In my opinion Maya till today has the best ballanced set of tools between
Polygon and NURBS.

With added NURBS support Blender would simply increase its usability
in other 3d sections beside motion picture and character modeling.

This ranges from product to architecture and others.

So go grab the source code and start adding those tools. Unless there are more devs who need it it is not going to be done.

what happend to nurbana integration? can’t be finished by some willing dev please? would be great to have good NURBS toolset
or what about this toolset? http://www.aria.uklinux.net/nurbs.php3
and use of 3dm format for compatibility with other nurbs softwares? http://www.opennurbs.org/

In case someone wants to give it a go, you can find it at https://svn.blender.org/svnroot/bf-blender/branches/nurbs/blender/ . Just “svn co https://svn.blender.org/svnroot/bf-blender/branches/nurbs/” should do the trick.

I have no time to do this either, but I saw something open-sourcish called ayam recently, maybe there is some potential for blender integration there.

(And as far as commercial CAD sw goes, for my money I would go with Ashlar-Vellum. They even rent their sw by the month these days.)

maybe this open source nurbs modeling kernel could be useful too http://www.smlib.com/smlib.html


I am not a coder - I would do it in case I would know how to.