"spiralize" offset curves for fabrication

[laurent_delrieu]

It is also possible to make a single path using this technique

Polyline on a surface

Hi, I am trying to create one single curve that covers all my surface that has holes in the middle. How can I do that? I started to divide the curve in points and interpolate them, but it goes over the holes. Something like in the image where I can varying the distance between the line. thanks [IMG_3898]