Workshop › Pool › Step 24 of 33

A power bar

What we are doing

A bar under the table shows the power: a dark bar as wide as the table, and over it an orange part as wide as power / MAX_POWER of it.

```js
// Power bar
ctx.fillStyle = '#334155'
ctx.fillRect(LEFT, 304, RIGHT - LEFT, 14)
ctx.fillStyle = '#f59e0b'
ctx.fillRect(LEFT, 304, ((RIGHT - LEFT) * power) / MAX_POWER, 14)
```

What it means

• The dark bar is 440 wide; the orange one 440 × power / 16: at power 8 it is half full.

Your turn

In draw, after the ball loop, leave an empty line and write the comment and the four bar lines.

Skills: Drawing on a canvas

← Choose the power A slingshot →

All steps

1. The room
2. The table
3. The cue ball
4. Draw the balls
5. The rack
6. Numbers on the balls
7. An aim line
8. Turn the aim
9. A shot is a velocity
10. Roll
11. Friction
12. Cushions
13. Aiming and rolling
14. Hide the aim while rolling
15. Count the shots
16. Balls that touch
17. Swap the push
18. Six pockets
19. In the pocket
20. Scratch
21. Balls left
22. Clear the table
23. Choose the power
24. A power bar
25. A slingshot
26. Press to aim
27. Pull back and let go
28. Smaller steps
29. Predict the hit
30. Draw the ghost ball
31. Where the hit ball goes
32. Your best
33. Build it yourself: two players