Workshop › Missile Command-style Defense › Step 2 of 35

Your missile base

What we are doing

In the middle stands your base: the place your interceptor missiles will fly from.

```js
const BASE = { x: 240, y: GROUND - 14 } // where your interceptors start

ctx.fillStyle = '#a3e635'
ctx.fillRect(BASE.x - 12, BASE.y, 24, 14)
```

What it means

• BASE is an object: its x is the middle of the field, its y the top of the base (14 above the ground).
• The base is a 24×14 green block centered on BASE.x.

Your turn

1. Under const GROUND = 370 write the BASE line.
2. Under the city loop's closing }, write the two base lines.

Skills: Drawing on a canvas

← Six cities to protect Draw again and again →

All steps

1. Six cities to protect
2. Your missile base
3. Draw again and again
4. Cities that can fall
5. Rubble
6. Move towards a point
7. Launch an enemy missile
8. One missile a second
9. Missiles on their way
10. Smoke trails
11. Impact
12. Fire an interceptor
13. Click the sky
14. Interceptors fly
15. An explosion that grows and shrinks
16. Explode on arrival
17. Draw the explosions
18. Impacts explode too
19. Caught in the blast
20. Chain reactions
21. Only your explosions count
22. Points for every missile
23. Show the score
24. Limited ammo
25. Waves
26. Each wave is harder
27. The end of a wave
28. The end
29. Play again
30. Wave, ammo and messages
31. Launch from anywhere
32. Some missiles will split
33. Split into three
34. A high score
35. Build it yourself: a crosshair