let cells;

// Starting at generation 0

let generation = 0;

// Cell size

let w = 5;

​

// Rule 30

let ruleset = [0, 1, 1, 1, 1, 0, 0, 0];

​

function setup() {

  createCanvas(640, 240);

  background(255);

  // An array of 0s and 1s

  cells = new Array(floor(width / w));

  for (let i = 0; i < cells.length; i++) {

    cells[i] = 0;

  }

  cells[floor(cells.length / 2)] = 1;

}

​

function draw() {

  for (let i = 0; i < cells.length; i++) {

    // Only drawing the cell's with a state of 1

    if (cells[i] == 1) {

      fill(0);

      // Set the y-position according to the generation.

      square(i * w, generation * w, w);

    }

  }

​

  // Compute the next generation.

  let nextgen = cells.slice();

  for (let i = 0; i < cells.length; i++) {

    let left = cells[(i - 1 + cells.length) % cells.length];

    let me = cells[i];

    let right = cells[(i + 1) % cells.length];

    nextgen[i] = rules(left, me, right);

  }

  cells = nextgen;

​

  // The next generation

  generation++;

}

​

// Look up a new state from the ruleset.

function rules(a, b, c) {

  let s = "" + a + b + c;

  let index = parseInt(s, 2);

  return ruleset[index];

}

​