Workshop › Snake › Step 14 of 28

Pick a spot for the food

What we are doing

The snake needs something to eat. placeFood picks a random cell on the board and keeps it in food.

```js
const COLS = canvas.width / CELL
const ROWS = canvas.height / CELL
let food

function placeFood() {
  food = { x: Math.floor(Math.random() * COLS), y: Math.floor(Math.random() * ROWS) }
}

placeFood()
```

What it means

• COLS and ROWS are how many cells fit: 400 / 20 = 20 each way.
• let food makes an empty variable that placeFood fills.
• Math.random() gives a number from 0 up to (not including) 1; times 20 is 0 to 19.99…; Math.floor cuts off the decimals, giving a whole column 0–19.

Your turn

1. Under const CELL = 20 write COLS and ROWS.
2. Under let dir = ... write let food.
3. Under let last = 0, after an empty line, write placeFood and the call placeFood().

Skills: Functions

← Move the whole body Draw the food →

All steps

1. Find the canvas
2. Get the pen
3. Paint the board
4. Think in cells
5. Keep the position in a variable
6. A function that draws
7. A function that moves
8. The game loop
9. Slow it down
10. A direction to move in
11. Steer with the arrow keys
12. A body made of a list
13. Move the whole body
14. Pick a spot for the food
15. Draw the food
16. Eat and grow
17. Never put food on the snake
18. A table of turns
19. No U-turns
20. Crash into the walls
21. Crash into yourself
22. The game over message
23. Show the score
24. One function that starts a game
25. Play again with Space
26. Remember the best score
27. Speed up as you grow
28. Build it yourself: through the walls