createCanvas(600, 600);

  noLoop()

  button = createButton("Regenerate!").mousePressed(buttonPressed)

}

​

function draw() {

  background(30);

  num_sections = int(random(3, 7))

  num_sub_sections = int(random(3, 7))

  w = width / num_sections

  h = height / num_sections

  points = []

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

    for (let j = 0; j < num_sections; j++) {

      x = j * w

      y = i * h

      points.push(generatePoints(2000, num_sub_sections, x, y, w, h))

    }

  }

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

    drawPoints(points[i]) 

  }

}

​

function buttonPressed() {

  print("!!!!")

  redraw()

}

​

function drawPoints(points) {

  let max_hue = 300

  // noStroke()

  push()

  colorMode(HSB, 300, 100, 100)

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

    let p = points[i]

    let hx = map(p.sx, 0, p.s, 0, (max_hue - 1) / 2)

    let hy = map(p.sy, 0, p.s, 0, (max_hue - 1) / 2)

    fill(hx + hy, 100, 100)

    noFill()

    stroke(hx + hy, 100, 100)

    circle(p.x, p.y, 3) 

  }

  pop()

}

​

function generatePoints(n, s, x, y, w, h) {

  let rx = randomProbabilities(s)

  let ry = randomProbabilities(s)

  let points = []

  for (let i = 0; i < n; i++) {

    let sx = chooseSection(rx)

    let sy = chooseSection(ry)

    let min_x = x + (sx / s) * w

    let max_x = x + ((sx + 1) / s) * w

    let min_y = y + (sy / s) * h

    let max_y = y + ((sy + 1) / s) * h

    let cx = Math.random() * (max_x - min_x) + min_x

    let cy = Math.random() * (max_y - min_y) + min_y

    points.push({x: cx, y: cy, sx: sx, sy: sy, s: s})

  }

  return points

}

​

function chooseSection(probabilities) {

  let r = Math.random()

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

    if (r < probabilities[i]) {

      return i

    }

  }

}

​

function randomProbabilities(n) {

  let randoms = []

  for (let i = 0; i < n; i++) {

     randoms.push(Math.random())

  }

  return accumulate(normalize(randoms))

}

​

function accumulate(a) {

  for (let i = 1; i < a.length; i++) {

    a[i] += a[i-1]

  }

  return a

}

​

function sum(a) {

  return a.reduce((b, c) => b + c)

}

​

function normalize(a) {

  return a.map(n => n / sum(a))

}

​