Noisy Ball

// By Roni Kaufman

​

let particles = [];

let n;

let colors;

let squiggliness = 1/200;

let count = 1;

let maxSize = 250;

let interval;

​

function setup() {

  createCanvas(windowWidth, windowHeight);

  colorMode(HSB, 100);

  noStroke();

  colors = [color(60, 90, 90, 100), color(65, 90, 90, 100), color(70, 90, 90, 100), color(90, 100), color(15, 90, 90)];

  background(10);

  updateParticles();

  interval = setInterval(updateParticles, 1000);

}

​

function draw() {

  for (let p of particles) {

    p.draw();

    p.move();

  }

}

​

function updateParticles() {

  particles = [];

  let r = count;

  n = count;

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

    let theta = map(i, 0, n, -PI, PI);

    let x_ = width/2 + r*cos(theta);

    let y_ = height/2 + r*sin(theta);

    let s_ = 3;

    let c_ = colors[floor(random(colors.length))];

    particles.push(new Particle(x_, y_, s_, c_));

  }

  count = (count + 5);

  if (count > maxSize) {

    clearInterval(interval);

  }

}

​

function Particle(x_, y_, s_, c_) {

  this.x = x_;

  this.y = y_;

  this.size = s_;

  this.c = c_;

  this.alpha = 100;

  this.dist = 1;

  this.move = function() {

    let theta = noise(this.x * squiggliness, this.y * squiggliness)*PI*4;

    let v = p5.Vector.fromAngle(theta, this.dist);

    this.x += v.x;

    this.y += v.y;

    this.dist *= 0.99;

    //this.alpha *= 0.95;

    this.size *= 0.95;

  }

  this.draw = function() {

    this.c.setAlpha(this.alpha);

    fill(this.c);

    circle(this.x, this.y, this.size);

    //this.c.setAlpha(100);

  }

}