let c;

let down;

let stars = [];

let sky = 0;

​

function setup() {

  createCanvas(windowWidth, windowHeight);

  x = width / 2;

  y = height / 2;

  c = 255;

​

  for (let i = 0; i < 1000; i++) {

    stars[i] = new Star(random(width), random(height), random(255), random(0.1, 3), random(1));

  }

}

​

function draw() {

  background(sky);

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

    stars[i].twinkle();

    stars[i].showStar();

  }

  //sky = map(mouseY, 0,height, 0,255);

}

​

​

class Star {

  constructor(tx, ty, tc, tf, td) {

    this.x = tx;

    this.y = ty;

    this.c = tc;

    this.f = tf;

    this.down = td;

  }

​

  showStar() {

    stroke(this.c)

    point(this.x, this.y);

  }

​

  twinkle() {

    if (this.c >= 255) {

      this.down = true;

    }

    if (this.c <= 0) {

      this.down = false;

    }

​

    if (this.down) {

      this.c -= this.f

    } else {

      this.c += this.f

    }

  }

}