How to smooth a curve but preserve area?

H i , in this picture for example we have a curve that we want to smooth it out but preserve the volume or area which is shown in black , the final result is made by hand [red] but i want to automate the process using grasshopper or rhino tools .

Do you mean just to keep the same area value?
in that case you can apply any smoothing process then scale by sqrt(area before/area after).

but from your image I’m guessing that rather what you want is a shape which smoothly fills in the concave parts without cutting into the original shape.
You can get this by combining a negative offset with a positive offset of the same amount: (7.6 KB)


btw @gustojunk

The same approach can be used in 3d with the new Shrinkwrap tool to smooth concavities but not convexities, like you were asking about here

To get a shape like if you tried to mill your input object with a spherical bit of radius r, shrinkwrap with offset r, then shrinkwrap that result with offset -r.


Jesus christ thank you man :heart_eyes:


Slick trick! (15.3 KB)


Thanks @DanielPiker, BTW, this looks really interesting:

I’d love to see some interactive booleaning way in Rhino. Or maybe is voxel-based? That’s what’s behind the shrinkwrap, right?


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