Glitch

const dead = [0, 0, 0];

const alive = [255, 255, 255];

const n = 500 ; // Resolution

let cells;

let g;

​

function setup() {

  const m = min(windowWidth, windowHeight);

  createCanvas(m, m);

  cells = new Float32Array(n * n).fill().map((e) => random(-1, 1));

  g = createGraphics(n, n);

}

​

​

function getValue(x, y) {

  x = (x + n) % n;

  y = (y + n) % n;

  return cells[x + y * n];

}

​

function draw() {

  g.background(dead).loadPixels();

  const aliveData = new Uint8Array(alive);

  const zoom = n / width;

  const mx = int(constrain(mouseX * zoom, 0, n - 1));

  const my = int(constrain(mouseY * zoom, 0, n - 1));

  cells[mx + my * n] = sin(frameCount);

​

  let next = new Float32Array(cells);

  for (let y = 0; y < n; y++) {

    for (let x = 0; x < n; x++) {

      const self = getValue(x, y);

      const neighbors =

        getValue(x - 1, y - 1) +

        getValue(x - 1, y + 1) +

        getValue(x + 1, y - 1) +

        getValue(x + 1, y + 1) 

      const neighbors1 =

        getValue(x - 2, y - 2) +

        getValue(x - 2, y + 2) +

        getValue(x + 2, y - 2) +

        getValue(x + 2, y + 2) ;

​

      const newValue =

        + self * 0.25 

      + (neighbors + neighbors1*0.25) * (mouseIsPressed ? -0.1 : 0.1);

      const i = x + y * n;

      next[i] = newValue;

      newValue > 0 && g.pixels.set(aliveData, i * 4);

    }

  }

  cells = next;

  g.updatePixels();

  image(g, 0, 0, width, height);

}

​