polygonal, nurbs, and subdivisions?

I’m trying to sell models on a 3d models website. When publishing a product it asks what type of geometry my model uses. the choices are unknown, polygonal, nurbs, and subdivisions. I’d like to tell potential buyers what it is rather than always selecting unknown. What is the difference between these and how do I know which my model uses? Thanks.

Polygonal: http://wordnetweb.princeton.edu/perl/webwn?s=polygonal
Most models are polygonal. The cube that loads when blender starts is a polygonal mesh. Any model that has faces is polygonal.

Subdivision surfaces: http://en.wikipedia.org/wiki/Subdivision_surfaces
Is a technique developed by Ed Catmull designed to extrapolate more polygons based of a simple mesh structure. We call it subsurf. If you used subsurf in your model then it is a subdivision surface. A model could be both polygonal and subsurfed.

Nurbs: http://en.wikipedia.org/wiki/NURBS
Fairly outdated method of modeling, still widely used in the manufacturing industries. It is a method of modeling that allows simple curves to define complex shapes. Sometimes nurbs surfaces are the best way to create something. (But I avoid them completely) If you use curves to create your object, and it is not converted to a mesh, it could be considered to be in this category as well.

well the new Nurbs being design are going to be a lot more powerfull soon hopefully

but you also have Curves ojbects

then you have the also the font object which i thnk are made with some sort of bezier curves too!

and also the lamps camera and empty objects in blender

so there are many type of objects in blender !

Note: for the subsurf modifier there are 2 algo available not only the catmult one!


NURBS is not oudated.

Well there is a reason that most professionals have switched to sub-d.
Here is a good article about the differences.

I say they are outdated for my purposes, at one time all we had was nurbs, now there are such better methods. A good polyonal mesh is soooo much more flexible than anything else, and far easier to work with. When it comes to texturing, weight painting, shape-keys, sculpting, and even final rendering, you are going to want a nice clean mesh IMO.

Now if you are doing industrial design, nurbs are the way to go. Or maybe as a starting point for a mesh, but once you learn good box modeling techniques, you really don’t need anything else.

ok, I get it now. thanks guys. but, why are nurbs good for industrial design compared to box modeling? and by industrial design do you mean all products I plan on selling? thanks.

he best way to explain is that Nurbs can be perfect. They can be precise down to the smallest detail, down to the millimeter. Good for designing a carbody that is going to be built by a machine.