Workshop › OutRun-style Racer › Step 19 of 44

Move the camera sideways

What we are doing

The car always stays in the middle of the screen, so steering moves the camera sideways and the road moves the other way. playerX is where we are across the road: 0 the middle, -1 the left edge, 1 the right edge.

```js
let playerX // -1 is the left edge of the road, 1 the right edge

  playerX = 0

    const near = project(-playerX * ROAD, -CAMERA_HEIGHT, z)
    const far = project(-playerX * ROAD, -CAMERA_HEIGHT, z + SEG)
```

What it means

• playerX times ROAD (half the road's width) is how far the camera is from the middle, in world units.
• The road's middle is then -playerX * ROAD to the side of the camera. Nearer segments are wider on screen, so they shift a lot and far ones hardly at all.

Your turn

1. Under let position write let playerX.
2. In reset, under position = 0, write playerX = 0.
3. In the first loop of draw, change the first 0 in the near and far lines to -playerX * ROAD.

Skills: Game states

← A pedal for phones Steering →

All steps

1. Sky and ground
2. Draw again and again
3. Perspective
4. One piece of road
5. A road made of segments
6. Where we are on the track
7. The road ahead
8. Stripes
9. Paint from far to near
10. Kerbs and a center line
11. Striped grass
12. Moving is one number
13. Which keys are down?
14. The gas pedal
15. Brake, coast and a top speed
16. Your car
17. Speedometer
18. A pedal for phones
19. Move the camera sideways
20. Steering
21. No turning on the spot
22. The grass is slow
23. Steering by touch
24. A track with curves
25. Bend the road
26. No jumps in the curve
27. Which segment am I on?
28. Curves pull you outwards
29. Other cars
30. Distance on a loop
31. Cars that shrink with distance
32. Traffic moves
33. Rear-end crash
34. Counting laps
35. Show the lap
36. A lap timer
37. Show the time
38. Best lap
39. Show the best lap
40. Racing or finished
41. The finish line
42. Finished!
43. Race again
44. Build it yourself: beat the clock