let pixelsPerFrame = 400;

​

​

function setup()

{

  createCanvas(400, 400);

  background(220);

}

​

​

function draw()

{

  for (let i = 0; i < pixelsPerFrame; ++i)

  {

    let x = pixel % width; 

    let y = floor(pixel / height);

    let gray = (x * y) % 255;

​

    stroke(gray);

    point(x, y);

    pixel += 1;

  }

}

​