var yPos = [];

var blues = [];

var speeds = [];

function setup() {

  createCanvas(400, 400);

  var count = 0;

  while (count < 1000){

  append(xPos,random(400));

  append(yPos,random(400));

  append(blues, random(256));

  append(speeds,random(0.5,2));

    count++;

  }

  noStroke();

}

​

function draw() {

  background(0,0,0,10);

  fill(0,0,255);

  var i = 0;

  while(i < xPos.length){

    fill(0,0, blues[i]);

  ellipse(xPos[i],yPos[i],5,5);

    yPos[i] = yPos[i] + speeds[i];

    xPos[i] = xPos[i] + random(-1,1);

    if(yPos[i] > 400){

    yPos[i] = 0;

}

     i++;

  }

}

​