var speed = 4;

​

function setup() {

  createCanvas(600, 380);

  background(0);

  noStroke();

  for (var i = 0; i < 600; i++) {

    stars[i] = new Star();

  }

}

​

function draw() {

 fill(0,180);// draw an alpha

 rect(0,0,width,height);

   //background(0);

  translate(width / 2, height / 2);

​

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

    stars[i].update();

    stars[i].show();

    stroke(255);

    strokeWeight(0.1);

    //line(0,0,stars[i].x,stars[i].y);

  }

}

​

function Star() {

  //this.x = random(-width, width);

  //this.y = random(-height, height);

  //this.z = random(600);

  this.position=createVector(random(-width,width),random(-height,height),random(600));

  this.velocity=createVector(0,0,-1);

  this.acceleration=createVector(0,0,-0.001);

​

  this.update = function() {

   // var mouse=createVector(mouseX,mouseY);

   // this.acceleration=p5.Vector.sub(mouse,this.position);

   // this.acceleration.setMag(0.01);

    this.velocity.add(this.acceleration);

    this.position.add(this.velocity);

    if (this.position.z <1) {

      this.position.z =600;

      this.position.x = random(-width,width);

      this.position.y = random(-height,height);

    }

  }

    this.show = function() {

      fill(255);

      stroke(255,150);

      strokeWeight(random(2));

      var sx = map(this.position.x / this.position.z, 0, 1, 0, width);

      var sy = map(this.position.y/this.position.z, 0, 1, 0, height);

      var r = map(this.position.z, 0, width, 10, 0);

      ellipse(sx, sy, r, r);

    }

​

}