Workshop › Tic-tac-toe › Step 2 of 33

Paint the board

What we are doing

Our first drawing: the whole canvas gets a dark navy background. Drawing is always two moves: pick a color, then fill a shape with it.

```js
ctx.fillStyle = '#1e1e2e'
ctx.fillRect(0, 0, canvas.width, canvas.height)
```

What it means

• ctx.fillStyle = '#1e1e2e' picks the fill color, a dark navy.
• ctx.fillRect(x, y, width, height) fills a rectangle. 0, 0 is the top-left corner, and canvas.width and canvas.height (300 and 300) make it cover everything.

Your turn

Leave an empty line under const ctx = ..., write the two lines, then press Run.

Skills: Drawing on a canvas

← Get the canvas and the pen The first grid line →

All steps

1. Get the canvas and the pen
2. Paint the board
3. The first grid line
4. Repeat with a loop
5. Finish the grid
6. The board as a list
7. A function that draws
8. Write an X
9. From cell number to position
10. Draw what the board holds
11. A color for each mark
12. Make a move
13. No playing on a taken cell
14. Listen for clicks
15. Which cell was clicked?
16. Clicks on any screen size
17. The eight winning lines
18. Find three in a row
19. Win, draw or go on
20. The round ends
21. Show who won
22. Light up the winning line
23. A function for a fresh round
24. Click to play again
25. A computer that picks a cell
26. The computer answers
27. Rule one: take the center
28. Rule two: win when you can
29. Rule three: block the opponent
30. Score a finished game
31. Look ahead: minimax
32. A computer that never loses
33. Build it yourself: keep score