Workshop › Whack-a-Mole › Step 6 of 18

Moles pop up

What we are doing

Every 700 ms a mole pops up in a random empty hole and stays up for one second.

```js
let nextPop = 0 // when the next mole pops up

function update() {
  if (now >= nextPop) {
    const empty = holes.filter((hole) => !isUp(hole))
    if (empty.length > 0) {
      const hole = empty[Math.floor(Math.random() * empty.length)]
      hole.upUntil = now + 1000
    }
    nextPop = now + 700
  }
}

  update()
```

What it means

• When it is time (now >= nextPop), pick among the holes without a mole.
• A random index into that list picks one; its mole stays up until one second from now.
• The next pop is 700 ms later.

Your turn

1. Under let now, write let nextPop = 0.
2. Above function draw() {, write update.
3. In loop, call update() before draw().

Skills: Game states, The game loop

← A mole in a hole Which hole was clicked? →

All steps

1. A green field
2. Nine holes
3. Draw the holes
4. A clock and a loop
5. A mole in a hole
6. Moles pop up
7. Which hole was clicked?
8. Whack!
9. Show the score
10. Click to start
11. Time's running
12. Time's up
13. Best score
14. How far into the round?
15. Faster and faster
16. Remember each hit
17. Floating +1
18. Build it yourself: combos