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

let _top = 0;

​

function setup() {

  frameRate(2);

  createCanvas(400, 400);

}

​

function draw() {

 // background(220);

  updateCells();

  drawCells();

  if (_top >= 400){

    background(220);

    _top = 0;

  } else {

    _top += 25;

  }

}

​

 function rules (a, b, c) {

    if      (a === 1 && b === 1 && c === 1) return ruleset[0];

    else if (a === 1 && b === 1 && c === 0) return ruleset[1];

    else if (a === 1 && b === 0 && c === 1) return ruleset[2];

    else if (a === 1 && b === 0 && c === 0) return ruleset[3];

    else if (a === 0 && b === 1 && c === 1) return ruleset[4];

    else if (a === 0 && b === 1 && c === 0) return ruleset[5];

    else if (a === 0 && b === 0 && c === 1) return ruleset[6];

    else if (a === 0 && b === 0 && c === 0) return ruleset[7];

  }

​

function updateCells(){

  let newcells = cells.slice();

  for (let i = 1; i < cells.length - 1; i++) {

    const left   = cells[i - 1];

    const middle = cells[i];

    const right  = cells[i + 1];

    const newstate = rules(left, middle, right);

    newcells[i] = newstate;

  }

  cells = newcells;

}

​

function drawCells(){

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

      if (cells[i] == 0) {

        fill(255);

    } else {

        fill(0);

    }

  stroke(0);

  rect(i*25, _top, 25, 25);

  }

}