Hello. Thank you all for your responses!

The only way I see to do it in a similar way is presented here: https://gfycat.com/LikableMinorEgg
Basically this process should be repeated twice in every node. Do you see any chance to speed it up?

I'm new here so I wanted to say hello to everybody! I was watching some video tutorials dedicated for Adobe Illustrator application and I've found something very interesting for me. Mainly, an author of this video was creating a simple illustration in that way the ends of contour lines were overlapp...