-
Notifications
You must be signed in to change notification settings - Fork 0
/
index.html
69 lines (59 loc) · 1.7 KB
/
index.html
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
<!DOCTYPE html>
<html lang="zh-CN">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>画板</title>
<link rel="stylesheet" href="style.css" />
</head>
<body>
<canvas id="canvas"></canvas>
<script>
let canvas = document.getElementById('canvas');
canvas.width = document.documentElement.clientWidth;
canvas.height = document.documentElement.clientHeight;
let ctx = canvas.getContext('2d');
ctx.fillStyle = 'black';
ctx.strokeStyle = 'black';
ctx.lineWidth = 16;
ctx.lineCap = 'round';
let painting = false;
let last;
function drawLine(x1, y1, x2, y2) {
ctx.beginPath();
ctx.moveTo(x1, y1);
ctx.lineTo(x2, y2);
ctx.stroke();
}
let isTouchDevice = 'ontouchstart' in
document.documentElement;
if(isTouchDevice) {
canvas.ontouchstart = (e) => {
let x = e.touches[0].clientX;
let y = e.touches[0].clientY;
last = [x, y];
}
canvas.ontouchmove = (e) => {
let x = e.touches[0].clientX;
let y = e.touches[0].clientY;
drawLine(last[0], last[1], x, y);
last = [x, y];
}
}else {
canvas.onmousedown = (e) => {
painting = true;
last = [e.clientX, e.clientY];
}
canvas.onmousemove = (e) => {
if(painting === true) {
drawLine(last[0], last[1], e.clientX, e.clientY);
last = [e.clientX, e.clientY];
}
}
canvas.onmouseup = () => {
painting = false;
}
}
</script>
</body>
</html>