Each of the little patches of vertices near an original edges junction ... these would be better if "deformed" just a tad. Instead of using "tighten" we can try "spherical" of our own design. That's what the link is for.
This link is also maybe nice. I like to read Javascript.
http://www.abecedarical.com/javascript/s...olver.html
This link is also maybe nice. I like to read Javascript.
http://www.abecedarical.com/javascript/s...olver.html