//create new ball using given arguments

  constructor(pos, vel, radius, color) {

    this.pos = pos;

    this.vel = vel;

    this.radius = radius;

    this.color = color;

  }

  //collision detection

  collide(check) {

    if (check == this) {

      return;

    }

    let relative = p5.Vector.sub(check.pos, this.pos);

    let dist = relative.mag() - (this.radius + check.radius);

    if (dist < 0) {

      let mov = relative.copy().setMag(abs(dist/2));

      this.pos.sub(mov);

      check.pos.add(mov);

      let otherNormal = relative.copy().normalize();

      let approachSpeed = this.vel.dot(otherNormal) - check.vel.dot(otherNormal);

      let approachVector = otherNormal.copy().setMag(approachSpeed);

      this.vel.sub(approachVector);

      check.vel.add(approachVector);

    }

  }

  //give life to the ball  

  move() {

    this.pos.add(this.vel);

    if (this.pos.x < this.radius) {

      this.pos.x = this.radius;

      this.vel.x = -this.vel.x;

    }

    if (this.pos.x > width-this.radius) {

      this.pos.x = width-this.radius;

      this.vel.x = -this.vel.x;

    }

    if (this.pos.y < this.radius) {

      this.pos.y = this.radius;

      this.vel.y = -this.vel.y;

    }

    if (this.pos.y > height-this.radius) {

      this.pos.y = height-this.radius;

      this.vel.y = -this.vel.y;

    }

  }

  //show the ball on the canvas

  render() {

    fill(this.color);

    noStroke();

    ellipse(this.pos.x, this.pos.y, this.radius*2);

  }

}

​

let balls = []; //stores all the balls

​

function setup() {

  createCanvas(window.windowWidth, window.windowHeight);

  let n = 10;

  //loop to create n balls

  for (i = 0; i < n; i++) {

    balls.push(new Ball(

      createVector(random(width),random(height)),

      p5.Vector.random2D().mult(random(5)),

      random(20,50),

      color(random(255),random(255),random(255))

    ));

  }

}

​

function draw() {

  background(0);

  //loop to detect collision at all instances

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

    for(let j = 0; j < i; j++) {

      balls[i].collide(balls[j]);

    }

  }

  //loop to render and move all balls

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

    balls[i].move();

    balls[i].render();

  }

}