How to make surface like this picture?

Hi Laurent!

This is an amazing effect and I have been following your plugin Nautilus since seeing this post. I notice that visually there are some similarity with another Nautilus component gradient flow (e.g. Gradient Flow on Mesh).

I’m wondering if you could share some insights on:
1 Are these functions related somehow?
2 Is it important to have a mesh for them? e.g. if I have a poly surface BREP, does it work? (From your description, Gradient Flow seems to be for mesh specifically)

Thanks a lot!