@article{Smith:1984:PFF,
  optpostscript = {},
  number = {3},
  month = jul,
  author = {Smith, Alvy Ray},
  optkey = {},
  optannote = {},
  url = {http://alvyray.com/Papers/PapersCG.htm#Graftals},
  localfile = {papers/Smith.1984.PFF.pdf},
  optkeywords = {},
  doi = {http://doi.acm.org/10.1145/964965.808571},
  optciteseer = {},
  journal = SIGGRAPH84,
  volume = {18},
  optwww = {},
  title = {{P}lants, {F}ractals, and {F}ormal {L}anguages},
  abstract = {Although fractal models of natural phenomena have received much
              attention recently, there are other models of complex natural
              objects which have been around longer in Computer Imagery but are
              not widely known. These are procedural models of plants and trees.
              An interesting class of these models is presented here which
              handles plant growth, sports an efficient data representation, and
              has a high ``database amplification'' factor. It is based on an
              extension of the well-known formal languages of symbol strings to
              the lesser-known formal languages of labeled graphs. It is so
              tempting to describe these plant models as ``fractal'' that the
              similarities of this class of models with fractal models are
              explored in an attempt at rapprochement. The models are not
              fractal so the common parts of fractal theory and plant theory are
              abstracted to form a class of objects, the graftals. This class
              may prove to be of great interest to the future of Computer
              Imagery. Determinism is shown to provide adequate complexity,
              whereas randomness is only convenient and often inefficient.
              Finally, a nonfractal, nongraftal family of trees by Bill Reeves
              is introduced to emphasize some of the paper's nongrammatical
              themes.},
  pages = {1--10},
  year = {1984},
}