function setup() {

  createCanvas(600, 600);

}

​

function draw() {

  background(100,100,200);

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

    ponds[i].show();

  }

  if (ponds.length>3) {

    ponds.shift();

  }

}

​

function mousePressed() {

  ponds.push(new Pond(mouseX, mouseY, 5));

  return false;

}

​

class Pond {

  constructor(x, y, t) {

    this.x = x;

    this.y = y;

    this.r = 30;

    this.t = t;

    this.alph = 255;

  }

  show() {

    for (let i=1; i <this.t+1; i++){

      noFill();

      stroke(255,255,255,this.alph);

      ellipse(this.x, this.y, this.r*pow(i,0.75));

    }

    this.grow();

  }

  grow() {

    this.r += this.r/50;

    this.alph -= 1;

  }

}