Chapter 7 More Algorithms

We begin this chapter with a fresh look at recursive curves—from an entirely different viewpoint. The instructions for drawing a curve can be in the form of a string. For instance the basic Z shape can be written “LL+L+LL-L-LL”, where L means “line segment”, + means turn forward, means turn backward. The idea, called “string rewriting system”, of using a string of characters to represent a recursive graphics figure was worked out by P. Prusinkiewicz, based on earlier work on modeling organism growth. See Saupe, D, Appendix C in Peitgen H-O, et al, Fractal Images, Springer-Verlag, 1988.