let rects = [];

let speed = 48;

const fps = 60;

​

function setup() {

  createCanvas(windowWidth, windowHeight);

  frameRate(fps);

  colorMode(HSB, 360, 100, 100, 100);

  angleMode(DEGREES);

  rectMode(CENTER);

  noStroke();

​

  for(var i=0;i<n;i++){

    let location = createVector(random(width),random(height));

    let col = color(255);

    let size = random(10,windowWidth/3.5);

    rects[i] = new randomRect(location,size,col);

  }

}

​

function draw() {

  blendMode(BLEND);

  background(214,100,45);

  blendMode(DIFFERENCE);

  for(let i=0;i<rects.length;i++){

    if(!rects[i].isDead){

      rects[i].draw();

      rects[i].decrease();

      if(rects[i].size<=0) {

        rects[i].isDead = true;

        let location = createVector(random(width),random(height));

        let col = color(255);

        let size = random(10,windowWidth/3.5);

        rects.push(new randomRect(location,size,col));

      }

    }

  }

  blendMode(MULTIPLY);

  background(325,100,100,100);

}

​

class randomRect{

  constructor(_location,_size,_col){

    this.x = _location.x;

    this.y = _location.y;

    this.size = _size;

    this.col = _col;

    this.isDead = false;

  }

  draw(){

    fill(this.col);

    rect(this.x,this.y,this.size,this.size);

  }

  decrease(){

    this.size-=speed/fps;

  }

}