Collatz

generative
Author

Pierre Casadebaig

Published

June 1, 2021

Curves parameterized from integer sequences and positioned according to basic botanical rules.

This study focus on a very simple generator, here a sequence of numbers generated from a set of rules. In this case, I used the Collatz sequence because it has a decreasing, random-looking pattern, which is a nice feature for plant structures (e.g. the internode distribution on a stem).
This sequence is used to define a curve, by mapping sequence elements to segment length, with a random angle between segments. Multiple curves are computed to constitute a node, and multiple nodes to constitute a stem / individual. Further recursion can be used to create populations of multiple individuals, with random or community-dependent features.
The main random elements are the initial value of the sequence, and the angle distribution between curve segments.

On this serie, rather than properly computing hidden line or polygons, I used an external algorithm (bitmap tracing) which had the nice side-effect of reshaping and merging some paths.