Workshop › Flappy-style Bird › Step 18 of 30

Remove the pipes you passed

What we are doing

A pipe that has left the screen on the left is useless, but it stays in the array forever. We keep only the pipes whose right edge is still on screen.

```js
pipes = pipes.filter((pipe) => pipe.x + PIPE_WIDTH > 0)
```

What it means

• filter makes a new array with only the items that pass the test.
• pipe.x + PIPE_WIDTH is the pipe's right edge; while it is above 0, part of the pipe is still visible.
• Without braces, the arrow function returns the answer of the comparison.

Your turn

In update, under the pipe loop's closing }, write the filter line.

Skills: Arrays and objects

← A pipe every 90 frames Is the bird level with a pipe? →

All steps

1. Get the canvas and the pen
2. Paint the sky
3. Draw the bird
4. A function that draws
5. A function that moves
6. The game loop
7. Gravity
8. A flap
9. Space, Up arrow or a tap
10. Wait for the first flap
11. The ground and the sky
12. Tell the player
13. A pipe as data
14. Draw the pipes
15. The world moves, not the bird
16. A new pipe at a random height
17. A pipe every 90 frames
18. Remove the pipes you passed
19. Is the bird level with a pipe?
20. Through the opening
21. Score each pipe once
22. Show the score
23. A function for a fresh start
24. Try again
25. One place where the game ends
26. Remember the best score
27. Show the best score
28. The same speed on every screen
29. No catching up after a pause
30. Build it yourself: a medal