Hi Paul, yeah it's pretty different than polygon modeling, in some other ways too - another thing that tends to throw people with a polygon modeling background off is that in NURBS modeling using trimming and boolean operations is the main way to do things.

A lot of people coming from a polygon modeling background have become accustomed to only using booleans as a kind of last resort since it causes a lot of problems with polygon modeling.

It can take a bit of adjustment to instead look to cutting and booleans as a primary tool.

Often times a particular area that is hard to get thinking of is that some shapes are more easily built by making a larger more simple extended piece initially, and then cutting away parts of it to get the final edge structure. I often see people from a polygon modeling background trying to draw in all the final edges from the start and then try to patch surfaces in between them, but a lot of the time cutting pieces off is way easier than that and more of a natural fit with the NURBS toolset.

Here are some other discussion threads that show some examples of this kind of stuff:

http://moi3d.com/forum/index.php?webtag=MOI&msg=3795.2
http://moi3d.com/forum/index.php?webtag=MOI&msg=4298.4
http://moi3d.com/forum/index.php?webtag=MOI&msg=4163.1
http://moi3d.com/forum/index.php?webtag=MOI&msg=2282.2


There are quite a lot of mechanical shapes that are handled really well by this technique, and the nice thing about doing cutting operations is that you can make cuts with 2D profile curves that are really quick to draw. So for the right kind of mechanical-ish type objects the NURBS modeling approach tends to make those kinds of models come together really fast from just 2D input, that's basically where the toolset shines.


For things that are more fully organic and aren't really well defined by 2D profile curves (think stuff like faces, creatures, etc...) then those types of models are not as good of a fit with the NURBS toolset and those kinds of things tend to work better with a polygon modeling program instead of MoI.

But that's also why MoI makes for a nice companion to use along with a poly modeler - it gives you a really different kind of toolset to use in the right situations.

- Michael