"Approximate NURBS Curve" node FreeCAD implementation

[rendetto]

This PR adds the PointsToBSpline OCCT method from FreeCAD for approximating points to a NURBS curve.

Example of Chord Length Parametrization:

Example of using Variational Smoothing:

EDIT:
I added an option where we can specify the knots explicitly:

The cool thing here is that we can utilize the "Generate Knotvector" node and use the metrics from it.

[rendetto]

I need some help with the docs. I'm not sure what I'm doing wrong so that this check is constantly failing.
The problem seems not in the files I'm editing even :/

[Durman]

I guess you have to add blank line after the list item or add 2 spaces in the start of the line after the list item.

[rendetto]

I guess you have to add blank line after the list item or add 2 spaces in the start of the line after the list item.

That's weird because match.rst it's not part of this PR.
Does that mean that failing checks doesn't prevent merging?

[rendetto]

@nortikin Should I try fixing match.rst? I saw you did the last changes.

EDIT: Fixed! :)

[portnov]

@rendetto it seems you have to rebase this branch to master:

1. in your master do git pull
2. in approximate_nurbs_curve_freecad branch do

$ git rebase master
$ git push -f origin approximate_nurbs_curve_freecad

[portnov]

Ah, merge worked as well :)

[rendetto]

Ah, merge worked as well :)

@portnov is it possible to merge it already? I've done all the changes I was planning.
If you don't find anything alarming please merge it.

Thanks

[portnov]

Suggestions:

• Rename "Type" parameter to "Metric".
• Rename "Uniform" metric to "Uniform (Points)", and "Chord Length" to "Chord Length (Euclidean)"
• (?) Add support for other metric types. You can calculate knot values with sverchok.utils.geom.Spline.create_knots.

[rendetto]

@portnov It's done 2ed47b8 but I'm not very proud :)

Can you take a look at the code changes? I deliberately used the mixed keys:
MANHATTAN, ChordLength, Uniform, CHEBYSHEV, Centripetal, X, Y, Z. It looks wonky but it's the most direct way.
Is it appropriate?

[portnov]

It's fine IMHO.

[rendetto]

Thanks. I've updated the docs accordingly. It should be ready for merge.