​

let snowflakes = [];

​

function setup() {

  createCanvas(500, 500);

}

​

function draw() {

  background('blue');

  let t = frameCount / 60;

  for (let i = 0; i < random(5); i++) {

    snowflakes.push(new Snowflake()); 

  }

​

  for (let flake of snowflakes) {

    flake.update(t); 

    flake.display(); 

  }

  // console.log(snowflakes.length)

}

​

class Snowflake {

  constructor() {

    this.pos = createVector(random(width), random(-50, 0));

    this.vel= createVector();

    this.initAngle = random(0, 2 * PI);

    this.size = random(2,5);

    this.radius = sqrt(random(pow(width / 2, 2)));

  }

  update(time) {

    let w = 0.6;

    let angle = w * time + this.initAngle;

    this.pos.x = width / 2 + this.radius * sin(angle);

    this.pos.y += pow(this.size, 0.5);

    if (this.pos.y > height) {

      let index = snowflakes.indexOf(this);

      snowflakes.splice(index, 1);

    }

  }

  display() {

    noStroke();

    fill(255, 255, 255, 100);

    ellipse(this.pos.x, this.pos.y, this.size);

  }

}