Workshop › 15 Puzzle › Step 2 of 27

The canvas and the pen

What we are doing

Games are drawn on a <canvas>, a rectangle of pixels. The page already has one with the id game. We find it and take its 2D drawing tools.

```js
const canvas = document.getElementById('game')
const ctx = canvas.getContext('2d')
```

What it means

• document.getElementById('game') finds the element whose id is game; we name it canvas.
• canvas.getContext('2d') gives the canvas's 2D drawing tools; we call them ctx.

Your turn

Write the two lines under the comment lines, above let tiles, and leave an empty line.

Skills: Drawing on a canvas

← A board in one list Paint the table →

All steps

1. A board in one list
2. The canvas and the pen
3. Paint the table
4. A function that draws
5. Row and column
6. Where each square is
7. Draw one tile
8. The number on the tile
9. All the tiles
10. Draw again and again
11. The solved board from N
12. Neighbours
13. Slide a tile
14. Click a tile
15. Arrow keys
16. Count the moves
17. Shuffle with real slides
18. Which boards can be solved?
19. Is it solved?
20. Remember the slide
21. Count the frames
22. Smooth sliding
23. Solved!
24. Show the win
25. Play again
26. A record to beat
27. Build it yourself: a timer