x: 25,

  y: 100

};

​

let speed;

let ballSize = 50;

​

function setup() {

  createCanvas(400, 400);

  background(220);

  initializeSpeed();

}

​

function draw() {

  clearCanvas();

  drawBall();

  updatePosition();

  updateSpeed();

}

​

function initializeSpeed() {

  speed = {

    x: random(-10, 10),

    y: random(-10, 10)

  };

}

​

function drawBall() {

  ellipse(pos.x, pos.y, ballSize, ballSize);

}

​

function clearCanvas() {

  background(220);

}

​

function updatePosition() {

  pos.x = pos.x + speed.x;

  pos.y = pos.y + speed.y;

}

​

function ballAtVertWall() {

  let ballAtRightWall = pos.x > width - ballSize/2;

  let ballAtLeftWall = pos.x < ballSize/2;

  return ballAtRightWall || ballAtLeftWall;

}

​

function ballAtHorzWall() {

    let ballAtBottomWall = pos.y < ballSize/2;

  let ballAtTopWall = pos.y > height - ballSize/2;

  return ballAtBottomWall || ballAtTopWall;

}

​

function updateSpeed() {

  if (ballAtVertWall()) {

    speed.x = -speed.x; 

  }

  if (ballAtHorzWall()) {

    speed.y = -speed.y; 

  }

}

​