Hi Mike, but also if you do a Rebuild of the curve the rebuilt version of the curve will have an "arc length" parameterization where the parameterization of the curve is based on distance and so has the same parameterization as a line anyway.

So just do a Rebuild (with the Refit to tolerance mode) on the starting curve if you see any uneven squishing in the surface-to-surface flow results and it should solve that problem - constructing a line with the same control point count should not be required.

The rebuilt curve will have an arc length parameterization even if you see unequally spaced control points on it, since the control point spacing and parameterization of knot values are synchronized in that case.

This is the main reason why several surfacing commands like Loft and Network, etc.. incorporate a rebuild step on the profile curves as part of the surfacing process, so that the surface generated will spread out evenly based on distance traveled along the curves rather than bunching up where parameter space is compressed or stretched.


It's not actually uneven control points all by itself that causes uneven parameterization, that's just a bit of a simplified explanation - you get uneven parameterization when the parameter values between knots are stepping at some kind of constant rate like just a value of 1 between each knot value while meanwhile the control points are stepping at some other distances than that. You do get a curve like that if you draw a control point curve and have unequal spacing in the control points that you placed though - a control point curve from Draw curve > control points has a uniform knot vector.

- Michael