The rulesets can be found in the rules.json file. The majority of the rule-sets were written by Paul Bourke. I found another very nice resource on rulesets by Dmytro Fedoriaka here. When known, I have added the author as part of the data in the json file.
If you would like to learn more about L-Systems, I highly recommend Daniel Shiffman's The Nature of Code book or his Coding Challenge on L-system fractal trees.
I was having an issue with the sketch freezing with certain fractal patterns, so I imposed some (somewhat arbitrary) contraints on the fractal level. I have added alerts when the level is above the maxLevel I have set for the ruleset, and it is automatically constrained at the maxLevel. Of course, the maxLevel field can be edited as desired.
The fractals start at different points on the canvas, and therefore need different translations. The images below show the L-systems with the starting point indicated by the red circle. If you switch fractals and don't see anything, it is most likely because the fractal needs to be translated in either the x or y direction.
By default, two L-systems are rendered. You can remove the second one by checking the "Remove ruleset" check-box.
