Hi Brian,

> Just wondered if rebuild uses weights?

Nope, rebuild does not use weights itself.

Weights in NURBS curves are primarily useful for generating conic sections related stuff, not really for general purpose fitting operations. They way they work is kind of hard to deal with intuitively, they work by a projection of 4D coordinates into 3D by dividing the x,y,z coordinates by the weight value. But the math works out well doing this for generating conic sections though.

They can sometimes be used as a curve editing tool, when you manipulate the weight it will have an effect of pulling the curve more towards that point. That's not very often used though but it's the main reason why I would add it in later on at some point.

- Michael