Repository navigation
Expand file tree
/
Copy pathscale.html
More file actions
61 lines (61 loc) · 2.05 KB
/
Copy pathscale.html
File metadata and controls
61 lines (61 loc) · 2.05 KB
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
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>多点缩放</title>
<style>
div{
width:300px;
height: 300px;
background: #ccc;
margin:100px auto;
font:100px/300px "宋体";
color: #fff;
text-align: center;
}
</style>
<script>
window.onload = function(){
function d2a(n){
return n*180/Math.PI;//弧度转成角度
}
var oDiv = document.querySelector("div");
var s = 1;
oDiv.addEventListener("touchstart",function(ev){
var oldS = s;
function getS(ev){//最终求出角度
var x1 = ev.targetTouches[0].pageX;
var y1 = ev.targetTouches[0].pageY;
var x2 = oDiv.offsetLeft + oDiv.offsetWidth/2;
var y2 = oDiv.offsetTop + oDiv.offsetHeight/2;
var x = x1 - x2;
var y = y2 - y1;
//console.log(x,y)
return Math.sqrt(x*x + y*y);//Math.atan2(y,x)求出了弧度
}
if(ev.targetTouches.length == 2){
var downS = getS(ev);
}
function fnMove(ev){
if(ev.targetTouches.length == 2){
s = getS(ev)/downS * oldS ;
//var d = downD - getD(ev);
oDiv.style.webkitTransform = "scale("+s+")";
}
//一开始默认的角度为0
}
function fnEnd(){
oDiv.removeEventListener("touchmove",fnMove,false);
oDiv.removeEventListener("touchend",fnEnd,false);
}
oDiv.addEventListener("touchmove",fnMove,false);
oDiv.addEventListener("touchend",fnEnd,false);
ev.preventDefault();
},false)
}
</script>
</head>
<body>
<div>1</div>
</body>
</html>