Chapter 02 - Lesson 03

Recursive Branching

Build from one branch to two branches, then to a full recursive structure.

Open full demo View source

Concept explanation

After a branch is drawn, the rule moves to its tip and draws two smaller branches. Each child branch repeats the same rule until depth reaches zero.

Try it

Build from one branch to two branches, then to a full recursive structure.

Code fragment

function branch(length, depth) {
  if (depth === 0) return;
  line(0, 0, 0, -length);
  branch(length * 0.67, depth - 1);
}

What to observe

  • Depth 1 is just the trunk.
  • Each level creates more endpoints.
  • The base case prevents endless drawing.

Small challenge

Increase depth one step at a time and estimate how fast the endpoints multiply.