Workshop › Tower Defense › Step 8 of 42

Enemies on the road

What we are doing

Enemies are kept in a list; each one is an object with its distance d. To draw one, pointAt gives its point in tiles, and the middle of that tile in pixels gets a red circle.

```js
let enemies

  enemies = []

  for (const e of enemies) {
    const p = pointAt(e.d)
    const x = (p.x + 0.5) * TILE
    const y = TOP + (p.y + 0.5) * TILE
    ctx.fillStyle = '#dc2626'
    ctx.beginPath()
    ctx.arc(x, y, 11, 0, Math.PI * 2)
    ctx.fill()
  }
```

What it means

Your turn

  1. Under let road write let enemies; in reset, under findRoad(), write enemies = [].
  2. At the end of draw, after the tile loops and an empty line, write the enemies loop.

Skills: Drawing on a canvas

All steps

  1. Measure the map
  2. A map of tiles
  3. Draw it every frame
  4. The road as corners
  5. Fill in the road
  6. Draw the road
  7. Walking by distance
  8. Enemies on the road
  9. Walk
  10. Off the end of the road
  11. Here they come
  12. Towers
  13. From a click to a tile
  14. Click to build
  15. Where can you build?
  16. Show the gold
  17. Show before you click
  18. Show the range
  19. Pick a target
  20. Fire!
  21. A hit hurts
  22. Homing bullets
  23. Fizzle out
  24. Gold for every kill
  25. Lives
  26. Health bars
  27. Build, then defend
  28. Space starts a wave
  29. The wave is over
  30. Stronger every wave
  31. Closer together
  32. Out of lives
  33. No building after the end
  34. The most waves survived
  35. The game over screen
  36. Play again
  37. The bottom bar
  38. Click to start
  39. A second tower: the cannon
  40. Tower buttons
  41. Splash damage
  42. Build it yourself: sell a tower