Workshop › Rhythm Lanes › Step 16 of 35

Close enough in time

What we are doing

Nobody presses at exactly the right frame, so a hit needs a window: a press counts if the note's time is within GOOD (9) frames of now, a little early or a little late. Otherwise nothing happens and the note keeps coming.

```js
const GOOD = 9

// A key press hits the closest note in its lane, if it is close enough in time.
function press(lane) {

  if (!closest) return
  const off = Math.abs(closest.time - frame)
  if (off > GOOD) return // too early: nothing happens, and the note is still there
  closest.hit = true
```

What it means

• off is how many frames the press is away from the note's time.
• if (off > GOOD) return leaves press before the note is marked, so a press far too early does nothing.

Your turn

1. Under LEAD write GOOD (above KEYS).
2. Above function press(lane) { write the comment.
3. In press, between if (!closest) return and closest.hit = true, write the two new lines.

Skills: Game states

← Hit the closest note One press, one hit →

All steps

1. A stage for the notes
2. The first lane
3. Four lanes with a loop
4. The hit line
5. A function that draws
6. The song as text
7. From text to notes
8. The clock decides where
9. Draw the notes
10. A clock that ticks
11. The game loop
12. Lanes that light up
13. Keys for the lanes
14. Show the keys
15. Hit the closest note
16. Close enough in time
17. One press, one hit
18. A message on the screen
19. Say Hit
20. Let the message go
21. Perfect or good
22. Keep count
23. Missed notes
24. Score
25. Hits in a row
26. The multiplier
27. The song ends
28. Stop the clock
29. Accuracy
30. The grade
31. The results
32. Play again
33. Best score
34. Lanes you can tap
35. Build it yourself: a speed setting