Fractal real time iterating

const MAX_ITERATIONS = 20;

const ITER_SHADE_SCALE = 255 / MAX_ITERATIONS;

const ESCAPE_RADIUS = 2;

const LIMIT = ESCAPE_RADIUS * ESCAPE_RADIUS;

const WIDTH = 700;

const HEIGHT = 550;

const PIXEL_SCALE = 1/200; // scales picture up

const X_MOD = 0.8; // pans picture left

​

function setup() {

  createCanvas(WIDTH, HEIGHT);

  background(100);

  noStroke();

  rectMode(CENTER);

  frameRate(1);

}

​

function iterateOnce(z, i, c)

{

  if (i <= MAX_ITERATIONS)

  {

    z = [

      sq(z[0]) - sq(z[1]) + c[0],

      2 * z[0] * z[1] + c[1]

    ];

    if (sq(z[0]) + sq(z[1]) > LIMIT)

    {

      return z, i, false;

    }

    i++

  }

  return z, i, true;

}

​

function complexize(x, y)

{

  c = [

    (x - WIDTH / 2) * PIXEL_SCALE - X_MOD,

    (y - HEIGHT / 2) * PIXEL_SCALE

  ];

  return c;

}

​

function draw() {

  let z;

  let i;

  let result;

  for (let x = 1; x <= WIDTH; x++)

  {

    for (let y = 1; y <= HEIGHT; y++)

    {

      result, iter = inMandelbrotSet(complexize(x, y));

      niter = 100 - iter;

      fill (iter * ITER_SHADE_SCALE);

      rect (x, y, 1, 1);

    }

  }

}