let directionY = "d";

​

let w = 50;

let h = 50;

let velocityX = 10;

let velocityY = 10;

let [x, y] = [0, 0];

​

function setup() {

  createCanvas(600, 600);

  frameRate(30);

}

​

function draw() {

  background(220);

  if (directionX == "d") {

    x = x + velocityX;

  }

  if (directionX == "e") {

    x = x - velocityX;

  }

  if (directionY == "b") {

    y = y + velocityY;

  }

  if (directionY == "c") {

    y = y - velocityY;

  }

  rect(x, y, w, h);

​

  console.log(x, y, directionX, directionY);

​

  if (x <= 0) {

    directionX = "d";

    velocityX = floor(random(0, 10));

  }

  if (x >= 600 - w) {

    directionX = "e";

    velocityX = floor(random(0, 10));

  }

  if (y <= 0) {

    directionY = "b";

    velocityY = floor(random(0, 10));

  }

  if (y >= 600 - w) {

    directionY = "c";

    velocityY = floor(random(0, 10));

  }

}

​