Hi Yannada,

T-Splines is forward and backwards compatible with NURBS. That is you can convert NURBS to T-Splines AND vice versa. Basically T-Splines is a specific expression of Catmull-Clark subdivision surfaces but what makes it so beautiful is that it is also a superset of NURBS, thus it bridges these 2 variations of expressing or modeling surfaces.

Modeling with T-splines is basically like modeling with any other variation of CC subdivision surfaces. The advantage of T-Splines is that you can model something with NURBS, then convert the NURBS into T-Splines and continue to refine the shape working in the same way as you were modeling in any standard SDS modeler. Of course the workflow can be reversed in the different direction.....starting modeling something using subdivision surfaces modeling style, then convert the model to NURBS and continue working NURBS style using Booleans, lofting, sweeping and trimming.

So to summarize T-Splines is a pretty cool thing, but unfortunatly it is currently only available as a plugin for Rhino. For those of us who prefer MoI we just have to wait for a while until a plugin for our favorite application becomes available.

.....P.s. one more thing, I just received a copy of an article on extended subdivision surfaces (ESUBS) today, which is some variation of bridging NURBS and Catmull Clark SDS, similar to T-Splines, but haven´t had time to read the paper yet.

But maybe (if we are lucky) we will have an ESUBS plugin for MOI in the future ;-)

an Importer / Exporter Modo / Rhino
http://www.luxology.com/whatismodo/plugins/plugin_rhino_translator.aspx
Don't know if that works with Moi :)

Hi Pilou,

you wrote:
> Don't know if that works with Moi :)

I don't think it will work with MoI since it only deals with polygon meshes and not NURBS - see this message earlier in this same thread: http://moi3d.com/forum/index.php?webtag=MOI&msg=1258.4

- Michael

You right soon posted some posts previous ;)

Hi Boatstalker,

>>Basically T-Splines is a specific expression or subset of Catmull-Clark subdivision surfaces
>>but what makes it so beautiful is that it is also a subset of NURBS



Petr

That's correct. The T-splines people say that it's able to duplicate any nurbs surface exactly, and any catmull-clark surface exactly. This of course must be under the right conditions, and with enough CPU power to handle complex objects. A t-spline is probably carrying more overhead than either Nurbs or Subd...

jonah

Hi Tyglik,

Thanks for correcting my errors. Guess I need to do my homework more properly ;-)

Anyway, for those interested in the topic of the convergence of NURBS and SDS the article on extended subdivision surfaces is higly recommended. It seems like ESUBS offer even more possibilities than T-NURCC surfaces (t-splines).
Here is the link:

http://portal.acm.org/citation.cfm?id=1138455

Happy modeling!!!