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Recursive Tree

Infinite complexity from simple self-similarity.

Controls

› Mouse X — change branching angle
› Mouse Y — change child branch length ratio

Recursion

Recursion in computer science occurs when a function calls itself. In this sketch, a single branch() function is called to draw the trunk. Before that function finishes, it calls itself twice to draw two smaller child branches at the end of the trunk. Those children then call themselves, creating an infinite loop of descending self-similarity.

The Base Case

If a recursive function never stops calling itself, it will crash the program (a Stack Overflow). To prevent this, every recursive function needs a Base Case. In this sketch, the base case is a simple length check: if the branch length drops below 4px, the function simply returns without breeding any more children.

L-Systems

This beautiful emergent shape mimics the natural branching structures found in trees, blood vessels, and lightning. This mathematical concept was pioneered by Aristid Lindenmayer in 1968 (known as an L-system) to model the growth processes of plant development using formal grammar and recursive replacement rules!