​

function setup() {

  createCanvas(600, 400);

}

​

function draw() {

  background("black");

  for (let i = 0; i < 30; i++) {

    let p = new Particle();

    particles.push(p);

  }

  for (let i = particles.length - 1; i >= 0; i--) {

    particles[i].update();

    particles[i].show();

    if (particles[i].finished()) {

      particles.splice(i, 1);

    }

  }

}

​

class Particle {

​

  constructor() {

    this.x = 300;

    this.y = 400;

    this.vx = random(-50, 50);

    this.vy = random(-5, -5);

    this.alpha = 50;

    this.color = color(random(100, 255), random(100, 255), random(100, 255));

  }

​

  finished() {

    return this.alpha < 0;

  }

​

  update() {

    this.x += this.vx;

    this.y += this.vy;

    this.alpha -= .5;

  }

​

  show() {

    noStroke();

    fill(this.color, this.alpha);

    ellipse(this.x, this.y, 16);

  }

​

}