Miss it, game over · Build Wall Ball

Right now a miss costs nothing. Let’s add three lives and a game-over. First, a lives variable at the top:

let lives = 3;

When the ball is missed we need to put it back in the middle. We’ll do that in two places, so let’s make a function for it — add serve() above update():

function serve() {
  bx = 64;
  by = 64;
  bdx = 1.5;
  bdy = rnd(2) - 1;   // a slightly random up/down angle
}

Now lose a life when the ball slips off the left edge. At the bottom of update(), add:

if (bx < 0) {
  lives = lives - 1;
  serve();
}

And stop the game when lives run out. At the very top of update(), add:

if (lives <= 0) {
  return;
}

💡

return here is an early exit — when lives reaches 0, the rest of update() is skipped, so the paddle and ball freeze. draw() still runs, so we can show a message.

Finally, show the lives and a game-over message. In draw(), add print('Lives: ' + lives, 78, 4, 8); near the top, and at the bottom add:

if (lives <= 0) {
  print('GAME OVER', 36, 56, 8);
}

Your whole program now — a real game with stakes:

let paddleY = 54;
const PH = 20;

let bx = 64;
let by = 64;
let bdx = 1.5;
let bdy = 1;

let hits = 0;
let lives = 3;

function serve() {
  bx = 64;
  by = 64;
  bdx = 1.5;
  bdy = rnd(2) - 1;
}

function update() {
  if (lives <= 0) {
    return;
  }

  if (key('ArrowUp')) {
    paddleY -= 2;
  }
  if (key('ArrowDown')) {
    paddleY += 2;
  }
  paddleY = mid(0, paddleY, 128 - PH);

  bx += bdx;
  by += bdy;
  if (by < 2 || by > 125) {
    bdy = -bdy;
  }
  if (bx > 122) {
    bdx = -bdx;
  }
  if (bx < 10 && by > paddleY && by < paddleY + PH && bdx < 0) {
    bdx = -bdx;
    hits = hits + 1;
  }
  if (bx < 0) {
    lives = lives - 1;
    serve();
  }
}

function draw() {
  cls(0);
  rectfill(124, 0, 127, 127, 6);
  print('Hits: ' + hits, 4, 4, 7);
  print('Lives: ' + lives, 78, 4, 8);
  rectfill(6, paddleY, 8, paddleY + PH, 7);
  circfill(bx, by, 2, 7);

  if (lives <= 0) {
    print('GAME OVER', 36, 56, 8);
  }
}