Loft leaves open hole

 From:  Michael Gibson
2157.6 In reply to 2157.5 
Hi Leonard,

> Is that the recommended approach, i.e., try to keep
> the number of splines to a minimum and add subtlety
> to the mesh in post (using a poly app, displacement, etc.)?

Yup, usually this is the best way to go - in general it is hard to do small fine detailed bumps in NURBS modeling.

This is sort of because the NURBS modeling workflow is focused on drawing profile curves to generate surfaces. This is kind of mis-match for fine localized details because something that has a bunch of raised areas in it for example is difficult to define clearly just by profile curves.

Like for instance a human face - even though you can draw a profile curve for a side silhouette for example, that profile does not define a very large area of the shape, as soon as you move even a slight distance away from the shape changes a lot from that profile. The profile in that case is more of a "single instant" capture of the shape and not a something that actually "drives" the shape.

Things like that where a single profile curve does not capture a somewhat extended part of the model are just not good to do with a profile-driven method. Instead those kinds of things work better to do in a sub-d or displacement app since those methods of working are better for changing just a localized area of the shape rather than a broad cross-section of it...

So I guess you may ask "why use NURBS modeling at all" ? :) The good part of NURBS modeling is there are also a lot of shapes that are well defined by profile curves and can come together very quickly when using a profile-driven workflow, often times man-made mechanical or industrial type shapes fall into this category.

> I know from threads that Moi3D is not for faces but should even
> the most subtle surface (organic) modulation be avoided?

Well, I guess it depends on what you mean by subtle... :)

It depends on the specific situation - there are circumstances where you can add subtle details like bulging or depressions if they are happening across a somewhat broader area. For an example check out the Pod tutorial: - the adjustments to the legs are pretty much like this.

Details that are need to be more localized to a smaller area of the model tend to be the ones that don't work as well.

But yeah in general the KISS idea is on the right track! :) It just tends to work best with NURBS when you follow that kind of method of building somewhat more simple pieces and then trimming and filleting them together.

- Michael