L-Systems are an algorithmic way of describing the growth of plants and cellular evolution by using recursive
instructions that generates fractal visual.
It uses Turtle Geometry : It's a way of drawing by
using sequential command.
The two main command are go forward and turn .
Within a tridimensional context, turn instructions are in the 3 different axis.
L-Systems are composed of 3 things :
- A Dictionary of all the command e.g.
F to go forward, & to rotate
clockwise on the X axis, etc...
- An Axiom (or premise in Touch Designer), it's the pre-existing shape. You'll often want to
have something before the algorithm begin it's work, a trunk for your tree for exemple.
- Rules, sequence of commands that you can call recursively
As an exemple, the default L-system in Touch designer uses this data:
premise:FFFA
A=!"[B]////[B]////B
B=&FFFA
It makes a nice 3D tree
-
!" Are related to size change depending on generation.
-
/& Are rotation commands
-
[] Are pop/push instructions, it lets you draw a branch and get back to drawing the trunk
References