Hi Burr,

> "I used scale from center", to bring the point stucture into length with
> the new line... Does that distribute them "Properly"? or is it just close.
> Would a "stretch" be different? Like distorting it more?

The problem is that it's not only the control point spacing that controls the parameterization of a curve (or of a U or V direction in a surface) - part of the information that makes up a curve is also a knot vector which also controls how the parameter space of a curve is formed.

That kind of control point spacing that you show there would be correct if the original curve had a uniform knot vector, but not if it had a non-uniform knot vector, if it had a non-uniform knot vector that knot vector would also need to be used in your new curve as well.

When you draw a new control point curve, it gets a uniform knot vector, one with even spacing between the knots.

You could solve what you show there by reconstructing the surface to have arc-length parameterization, that will then make it have a distance-based parameterization and so it will behave the same as a line, then you do not need to try to recreate any control point spacing.

You would reconstruct that extruded surface to have arc length parametrization in its bendy direction by extracting out the profile curve, running Rebuild on it with the refit to tolerance mode, and then re-extruding the rebuilt curve back out again.


But often if you're just using an extruded surface in surface-to-surface flow you can just get the same result by using curve-to-curve flow instead and like I mentioned previously curve-to-curve flow is itself based off of distance traveled along each curve and so it not sensitive to parameterization at all.

Do you have some flow example that you could show where you think you need to recreate that control point spacing? I can then show you how to avoid the need for it - the answer will be though to either use Rebuild on your curve before constructing a surface out of it or to use curve-to-curve flow instead of surface-to-surface flow.


- Michael