Hi Michael,

Many thanks - your explanation and the links helps my understanding a little more at least. I can't help thinking though, that being able to play with a mathematical model of a NURBS curve, where all the parameters can be interacted with, would really help.

Are you aware of anything equivalent to this Cubic Splines example on desmos.com, for a NURBS curve?
...some time later...BINGO - these interactive NURBS example should help a lot:
http://geometrie.foretnik.net/files/NURBS-en.swf
http://ibiblio.org/e-notes/Splines/NURBS.htm
http://ibiblio.org/e-notes/Splines/None.htm
I found this page also helpful: http://www.miaumiau.cat/2010/04/nurbs-in-flash-part-1/

(These were the previous closest I came to finding anything useful, [left in because they look interesting] but they're all 'only' NURBS libraries, not interactive examples:
http://verbnurbs.com/
http://threejs.org/
http://libnurbs.sourceforge.net/)

Where this is all leading ultimately, is that I think I want to be able to take a NURBS curve I've drawn in MoI that matches my requirements graphically, then convert/export/derive the mathematical expression of it and embedded that a MoI javascript. Why, because I'm struggling to achieve what I want using a polynomial expression, and I still need the javascript to further deform the geometry, regardless of whether the geometry is expressed as a polynomial or NURBS function.

Any ideas/suggestions appreciated.

Thanks again,
Hamish

Hi Hamish, well trying to do a full NURBS evaluator in self contained script code is fairly complicated, if you can deal with a limited number of control points it would probably be a lot easier to just focus on doing Bezier evaluation, that's a lot simpler.

In the future I do want to make evaluation of curves at specific parameter values available to script but currently it is not part of the script interface.

- Michael

Thanks Michael.

Another idea - what about simply exporting my 'nice' NURB to points (existing script IIRC) and then embedding those points in my script and drawing a 'through points' curve using the existing function? Or am I going to add lumps / loose some smoothness?

-Hamish

Hi Hamish, that sounds like it could be a possibility, but yes it can be possible to introduce lumpy shapes using "through points" although if you have regular spacing that could help avoid that.

- Michael

Thanks Michael.
- Hamish