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Introduction

LGrammar implements a two-dimensional and a three-dimensional graphics tool for evaluating Lindenmayer grammars. These grammars are characterized by having no terminal symbols and by performing all possible symbol replacements in parallel for each step.




Meaning of 2D Turtle Symbols





Meaning of 3D Turtle Symbols





Enter a New Grammar




Choose Colors


If you click the Color button in the applet threre'll appear a window with 2 color palettes. In the first one you can choose between the 3 standard palettes

by pressing the according button.
The second palette is for creating your own color order. Click at any field in the first palette and once again at any in the second one to copy a color. To tell the system that it should draw with the second palette, click the accept button.
The '#' symbol at the according label indicates the current color palette.



Stochastic Grammars


Using individual values as probabilities for a rule after the equal sign results in defining stochastic grammers. Here, is it allowed to have several rules for the same symbol, however, the sum of all probability values for this symbol has to be 1, e.g.:


Load Examples


If you press the Load button, you can choose between several examples. Just add the according filename at the and of the indicated URL in the button textfield, maybe you can use the copy and paste mechanism of your system. Confirm this by clicking the ok button.
Because of security restriction of java/netscape it's only possible to save your own grammars in the interpreted version.


Some Tips




Literature


P. Prusinkiewicz, A. Lindenmayer:
The SAlgorithmic Beauty of Plants
Springer-Verlag, New York, 1990

Chr. Drabek (in German)
Implementierung von L-Grammatiken zur Erzeugung von Graftalen
Diplomarbeit no. 986, Univ. Stuttgart, Fakultaet Informatik, 1993


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