Hi Mark,

> Would it be possible to generate these meshes as editable geometry
> (straight line "curves" and flat surfaces, basically nurbs "polygons")
> for re-use within MoI (similar to what your obj wireframe import script
> allows)?

Usually it is not so good to make NURBS objects out of a tremendous number of tiny facets.

NURBS have a very general purpose trimming mechanism, with the concept of an "underlying surface", which also includes 2 chunks of stuff for every trim curve, a UV curve that lives in the parameter space of the surface, and then also a 3D curve. All this structural stuff tends to be why NURBS are good at booleans - when you boolean 2 NURBS solids, the underlying surfaces of each get to stay exactly the same and only new trim curves have to be calculated. This tends to avoid fragmentation into a bazillion little slivery pieces which is what happens with polygon-mesh booleans - that is one reason why polygon mesh booleans just do not tend to work very well...

However, this kind of advanced and generalized structure for trimming is also heavier than the edge structure of a polygon mesh object.

NURBS can be nice and lightweight in data size when you are using them as they were originally intended - which means for example having a sphere represented as one sphere surface.

But if you instead try to make a sphere made up of thousands of tiny facets, that is not really how NURBS are designed to be used, and in that case the NURBS structure becomes quite memory consuming, since you now have quite a large number of trim curves.

So to make a long story short - although it is technically possible to make a conversion like you are talking about, it can result in a structure that is not really suited well for NURBS and can consume too much memory.

That means it would need to be a kind of special purpose thing, not really a general tool to use in normal circumstances.... That's why I did not make it as a built-in type thing, not yet anyway.

- Michael

Hi Mark, also I should probably mention that most likely the real solution to what you are talking about, like being able to rotate or manipulate polygon data in MoI, will be to have MoI support polygon data as a separate kind of object in addition to NURBS data.

But I haven't tried to do that yet though, since it kind of opens up potential for a lot of confusion for how those different kinds of data should interact with one another.

It has helped to keep MoI's interface nice and streamlined by having it focused on dealing only with NURBS data and not polygons yet.

Right now I kind of expect that if you need to work on polygon data that you would use a different program than MoI to do it, like for example Silo or Modo.

- Michael

Thanks Michael,

MoI keeps on getting better and better!

Jesse