Workshop › Tetris-style Blocks › Step 19 of 32

One function starts a game

What we are doing

To play again later we must be able to set everything back to the start. newGame() empties the board and brings the first piece; the variables are declared at the top without values.

```js
let board
let piece
let lastDrop = 0

function emptyRow() {
  return Array(COLS).fill(0)
}

function newGame() {
  board = Array.from({ length: ROWS }, emptyRow)
  spawn()
}

newGame()
requestAnimationFrame(loop)
```

What it means

• let board and let piece move above emptyRow, without values.
• newGame() gives board a fresh, empty well and spawns the first piece. It replaces the spawn() call at the bottom.

Your turn

1. Move the three let lines above function emptyRow(), and make let board empty.
2. Under emptyRow write newGame.
3. At the bottom, replace spawn() with newGame().

Skills: Game states, Functions

← Land and lock When the pile reaches the top →

All steps

1. The well
2. The board as rows of numbers
3. Draw one cell
4. Draw the whole board
5. The number is the color
6. A piece is a small grid
7. A list of shapes
8. All seven pieces
9. Does it fit inside the well?
10. Blocks are in the way
11. Try, then move
12. Move with the arrows
13. Turn a matrix
14. Turn with Up
15. Wall kicks
16. Falling by itself
17. A random piece at the top
18. Land and lock
19. One function starts a game
20. When the pile reaches the top
21. Game Over on screen
22. Play again
23. Clear full rows
24. Points for lines
25. The side panel
26. Levels
27. Faster every level
28. A fair bag of pieces
29. The next piece
30. Drop it
31. The ghost piece
32. Build it yourself: hold a piece