Workshop › Pong › Step 4 of 26

The whole net

What we are doing

A for loop repeats the dash every 30 pixels from the top to the bottom: 15 pixels of dash, 15 of gap.

```js
for (let y = 0; y < canvas.height; y += 30) {
  ctx.fillRect(canvas.width / 2 - 2, y, 4, 15)
}
```

What it means

• let y = 0 starts a counter at 0; y < canvas.height keeps going while it is above the bottom; y += 30 adds 30 after each round.
• So dashes are drawn at y = 0, 30, 60, ... 390: 14 of them.

Your turn

Replace the dash line with the loop (the fillRect inside uses y). Press Run.

Skills: Loops

← One dash of the net Two paddles →

All steps

1. Get the canvas and the pen
2. A black court
3. One dash of the net
4. The whole net
5. Two paddles
6. A function that draws
7. The game loop
8. Remember held keys
9. Move the paddles
10. Stay on the court
11. The ball
12. The ball moves
13. Bounce off the top and bottom
14. Does the ball touch a paddle?
15. The paddles hit back
16. Serve again
17. Keep the score
18. Show the score
19. First to five
20. Who won?
21. Play again
22. Aim with the paddle
23. Faster every hit
24. A computer opponent
25. One player or two
26. Build it yourself: a serve pause