Turn a grid of tubular surfaces into polylines

I’m trying to turn the grid of surfaces and polysurfaces attached into a…you might call it a mesh of polylines from the intersections. This is a simple sample section. I’ve done this before but wondering if there are any smarter ideas, if there even might be some kind of not-actually-automated procedure as this is something I need to do a lot of right now but not so much in the future. The “intersections” don’t even need to perfectly align, a 1/2" tolerance is fine.

extract polyline grid sample.3dm (275.2 KB)


I gave a shot at your problem using Grasshopper.
I managed to rebuild the rail used to sweep those pipes from tweening two isocurves, and then approximating these rails by polylines based on intersections. However this only works in this case because :

  • your pipes are made of two half-cylinders.
  • the rails actually intersect well.

You could give this a try on other samples, and get back to the forum if further development is required.

ExtractPipeRails.gh (13.0 KB)

Thanks, it had trouble on a more complex model where things don’t necessarily intersect perfectly, but food for thought…