let rows = [];

const cellSize = 4;

let currentRow = 0;

​

function setup() {

  createCanvas(765, 400);

  background('black');

  const numCells = width / cellSize;

  for (let i = 0; i < numCells; i++) {

    cells[i] = round(random(0,1));

  }

  cells[round(numCells / 2)] = 1;

  const numRows = height / cellSize;

  for (let i = 0; i < numRows; i++) {

    rows[i] = round(random(0,1));

  }

  rows[round(numRows / 2)] = 1;

}

​

function draw() {

  fill('white');

  noStroke();

  translate(0, currentRow * cellSize);

  currentRow++;

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

    if (cells[i] == 0) {

      fill('black');

    } else {

      fill('white');

    }

    rect(i * cellSize, 0, cellSize, cellSize);

  }

  let newCells = [];

  let newRows = [];

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

    for (let j = 0; j <rows.length; j++){

    const rowTop = rows[i - 1] ??0;

    const left = cells[i - 1] ?? 0;

    const rowMiddle = rows[i];

    const middle = cells[i];

    const rowBottom = rows[i +1] ?? 0;

    const right = cells[i + 1] ?? 0;

    const sum = rowTop +  right + rowBottom;

    if (sum == 2 || sum % 2) {

      newCells[i] = 1;

    } else {

      newCells[i] = 0;

    }

  }

  }

  cells = newCells;

  rows = newRows;

}

​

​