How to Taper Protrusion on a Twisted Vase

Hi, I am trying to create a vase of some kind, and wanted to have a protrusion that wraps around the vase. I am able to modify a few of the points in each curve to stick out, and then add a twist to the planes to make it wrap around the vase.

However, I’m stuck on how to taper the ends of the protrusion. Ideally, I would like the bit that sticks out to taper down to almost nothing on the top and bottom curves of the vase.

It feels like the answer should be obvious but no matter how I modify the data I can’t get it to apply the protrusion and also taper each successive protrusion. Thanks for any help in advance!


Vase_Help.gh (11.5 KB)

Well I thought I could whomp up a quicky solution for this, but noooooo…it’s more complicated than I expected.


I used a Loft made from 3 curves: one with a full spout (the top curve), one with a small spout (middle curve), and a plain circle for the bottom curve. This lofted OK but produces an unpleasant result because of the way Loft transitions from the small spout to a plain circle.

It looks like you are going to need a bunch of intermediate curves like you showed in you original image, each with a smaller spout size, and with the final one being very small spout indeed.

I used a pretty crude method for making the upper LOft curves - there’s probably a much better way to do this.
bb1.gh (15.2 KB)

I don’t know if I understood your request correctly.

That does look pretty close to what I was trying to describe! Each successive loop protrudes more than the last. I was trying to taper in both directions like the attached picture, but I’ll mess around with what you showed. Thanks!

Why do you want to loft so many curves?

I’ll try that too.
Vase_Help a.gh (29.8 KB)


Create a curve in Rhino and make it go up and down in 2D space, then sporph it

vase.gh (15.6 KB)

Or use the twist component…

vase_sporph_twist.gh (16.1 KB)

My approach uses data trees and a graph mapper. You should be able to control how tapered the protrusion becomes near the top and bottom. Let me know if it helps.


cole_vase_01.gh (17.9 KB)

Best,
~CH

Amazing, that’s actually exactly what I had in mind. And the solution isn’t massively complicated either. Thank you very much!