포락선(envelope)과 curve stitching
http://bomber0.myid.net/ (토론)님의 2011년 11월 14일 (월) 05:07 판
Curve Stitching or String Art.
http://playingwithmathematica.com/2011/04/27/curve-stitching-with-mathematica/
http://britton.disted.camosun.bc.ca/string_art/jbstringart.htm
http://www.wikihow.com/Create-a-Line-Design
http://en.wikipedia.org/wiki/B%C3%A9zier_curve#Quadratic_curves
envelope
http://jwilson.coe.uga.edu/Texts.Folder/Envel/envelopes.html