Workshop › Battleship › Step 21 of 35

Take turns

What we are doing

Battleship is played in turns. After your shot it is the computer's turn, and a timer makes it wait half a second before it shoots, so you can see what happens.

```js
const THINK = 30 // frames the computer waits before it shoots
let turn // 'you' or 'them'
let timer

  turn = 'you'

  if (state !== 'playing' || turn !== 'you' || myShots[r][c]) return

  turn = 'them'
  timer = THINK
```

What it means

• turn says whose turn it is; the game starts with yours.
• playerShoots refuses to shoot when it is not your turn.
• After a shot that did not win, the turn passes and the timer starts at 30 frames.

Your turn

1. Under HOME, write THINK; under let theirShots, write turn and timer.
2. In reset, under theirShots = grid(null), write turn = 'you'.
3. In playerShoots, add turn !== 'you' || to the first line, and write the two lines at the end.

Skills: Game states

← A record of their shots The computer shoots back →

All steps

1. A 10 by 10 sea
2. A function for any sea
3. Your own sea
4. Draw again and again
5. Grids and ships as lists
6. A random fleet
7. Two fleets
8. Which ship is here?
9. Fire at a square
10. Show the shots
11. Your shot
12. Tap to fire
13. A message line
14. Hit or miss?
15. See your own fleet
16. Sinking ships
17. Darker hits on a sunk ship
18. Outline sunk ships
19. Win in as few shots as you can
20. A record of their shots
21. Take turns
22. The computer shoots back
23. You can lose too
24. A heat map
25. Shoot the hottest square
26. Hunt around a hit
27. See the heat map
28. H for heat
29. Show their ships at the end
30. A keyboard cursor
31. Move with the arrows
32. Fire with Enter, play again
33. Your best game
34. A side panel
35. Build it yourself: ships apart