Escape-time Visualization Method for Language-restricted Iterated Function Systems

Przemyslaw Prusinkiewicz and Mark Hammel
Department of Computer Science
University of Calgary
Calgary, Alberta, Canada T2N 1N4
e-mail: pwp|


The escape-time method was introduced to generate images of Julia and Mandelbrot sets, then applied to visualize attractors of iterated function systems. This paper extends it further to language-restricted iterated function systems (LRIFS's). They generalize the original definition of IFS's by providing means for restricting the sequences of applicable transformations. The resulting attractors include sets that cannot be generated using ordinary IFS's. The concepts of this paper are expressed using the terminology of formal languages and finite automata.

Keywords: fractal, iterated function system, escape-time method, graphics algorithm, formal language, finite automaton.


  • Przemyslaw Prusinkiewicz and Mark Hammel. Escape-time Visualization Method for Language-restricted Iterated Function Systems. In Proceeding of Graphics Interface '92, pages 213-223, May 1992. Held in Vancouver, British Columbia, 11-15 May 1992.

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