Hi Michael

Sorry for my late answer. I wanted to wait with a reply until I gained a little bit more knowledge in general.

Even though I still don't think I understand why there is no surface like you stated?

For a calculation of the center curve I am thinking of first slicing the tube/solid/shape in little pieces. Then find the midpoint for each piece by integration. Then connect the midpoints to a single center curve and finally smooth out the edges if need by some smooth algorithm.

The smaller pieces (and thereby larger amounts) the better approximation for the curve. And of course calculation and processor time will increase:

Example with tube and cuts.








I briefly checked the skeleton about dividing the surface into minor shapes. I might have to dig deeper into this.


>Sorry I'm not really understanding what the end goal is here. Do you want the tube to slice away additional area of base solid to extend the cut out area?

<Or is the tube going to sit on top of the solid like as if you put a line of grout squeezed onto it or something like that?

Yes exactly - well a bit of both. My idea is that I can cut out an interesting shape and then change the surface on that shape. For example it could be some kind of wall design where the wall goes "in and out". Along the wall there could be a cut out for wires. The cut out could come from a curve and there after the wire gets put in the hole.

It could also be to slice additional area as you suggested and then put a wire in that fit that cut (the same wire).