FitCrv moment of realization

I just realized that if a polycurve is composed of curves which are tangent, the result of “FitCrv” is a single curve, but multiple curves otherwise.

Why do I discover this ater 20 years of using Rhino ?
Here’s the online help for this command : no word on curve merging.

And why isn’t there an option to either output a single curve or not ?
I’m sobbing over the useless hair pulling from all these years…

FitCrv has an angle tolerance setting, kink locations greater than that angle tangent difference are preserved, less than that angle, kinked portions are merged into a single spline.


Hi Mitch,

This should be explained in easy to understand terms in the help file / options of the command.
The word “merged” , for example, could be useful.

“When a kink in the input curve is this angle or less from tangent, the kink will be refit smoothly, otherwise the output curve will also have a kink at that location.”

I suppose there could be a more elaborate explanation, best might be a small illustrated example.

I agree.
If I knew I just needed to use “Match” with “Tangent” option to ensure my polycurve would be rebuilt as a single curve, it would have saved me so much time !
I even made a Grasshopper definition to rebuild such polycurves, but in a more intelligent way than the “Rebuild” command, and easier than “RebuildNon-Uniform”… all this for nothing.

@KelvinC :mag:

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I’ve used Rhino for half a year instead of 20 years, and I use this all the time. :grimacing:

(Sorry to pour salt into your wound.) :joy:

Seriously, that’s why I’ve spent far too much time on this forum trying to essentially crash course learn Rhino, and soak up as much knowledge as possible (and I must say that this and Blender is by far the most helpful communities I’ve found online).

On a related note, when merging surface and rebuilding them, is there a trick to not have the control points completely freak out? In certain situations, I’d rather have a clean looking hull rather then a super tight fitting surface.

The AngleTolerance option has been added since v5.
The topic has been updated with this GIF animation. (AngleTolerance=10)


Ha, I have used Rhino for the same amount of time, and I have never used FitCrvl!

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