Subject: L-Systems

Q13: What are L-systems?

A13: A L-system or Lindenmayer system is a formal grammar for generating strings. (That is, it is a collection of rules such as replace X with XYX.) By recursively applying the rules of the L-system to an initial string, a string with fractal structure can be created. Interpreting this string as a set of graphical commands allows the fractal to be displayed. L-systems are very useful for generating realistic plant structures.

Some references are:

1. P. Prusinkiewicz and J. Hanan, Lindenmayer Systems, Fractals, and Plants, Springer-Verlag, New York, 1989.
2. P. Prusinkiewicz and A. Lindenmayer, The Algorithmic Beauty of Plants, Springer-Verlag, NY, 1990. ISBN 0-387-97297-8. A very good book on L-systems, which can be used to model plants in a very realistic fashion. The book contains many pictures.

More information can be obtained via the WWW at:

L-Systems Tutorial by David Green

http://life.csu.edu.au/complex/tutorials/tutorial2.html

http://www.csu.edu.au/complex_systems/tutorial2.html

Graphics Archive at the Center for the Computation and Visualization of Geometric Structures contains various fractals created from L-Systems.

http://www.geom.umn.edu/graphics/pix/General_Interest/Fractals/