const perloop = 20;

​

function setup() {

  createCanvas(500,500);

}

​

function draw() {

  loadPixels();

  let d = pixelDensity();

  let img = 4 * (width * d) * (height * d);

  let thing = millis()*0.0002

  for (let i = 0; i < img; i += 4*perloop) {

    let index = i/4/d;

    let y = index/(width*d);

    let x = index%(width*2)

    let val = noise(0.5*x/width,0.5*y/height,thing)*255

    if(val<127){val=0;}

    else {val=255;}

    for(let k=0;k<perloop;k++){

      for(let j=0;j<3;j++){

        pixels[i+4*k+j] = val;

      }

      pixels[i+4*k + 3] = 256;

    }

  }

  updatePixels();

  counter++;

  if(counter>10){

    print(frameRate());

    counter = 0;

  }

}