检测碰撞
2017-04-18 本文已影响0人
洛洛kkkkkk
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<style type="text/css">
.redDiv{
width: 400px;
height: 400px;
background-color: greenyellow;
position: relative;
margin: 100px auto;
}
.yellow{
width: 50px;
height: 50px;
background-color: yellow;
position: absolute;
}
</style>
</head>
<body>
<div class="redDiv"></div>
<div class="yellow"></div>
</body>
<script type="text/javascript">
var redDiv=document.querySelector(".redDiv");
var yellow= document.querySelector(".yellow");
yellow.onmousedown = function (ev) {
var x=ev.offsetX;
var y=ev.offsetY;
document.onmousemove = function (e) {
yellow.style.left=e.clientX-x+'px';
yellow.style.top=e.clientY-y+'px';
// 碰撞检测
// 1.蓝右>红左
// 2.蓝顶<红底
// 3.蓝底>红顶
// 4.蓝左<红右
if(yellow.offsetLeft+yellow.offsetWidth>=redDiv.offsetLeft && yellow.offsetTop<=redDiv.offsetTop+redDiv.offsetHeight && yellow.offsetTop+yellow.offsetHeight>=redDiv.offsetTop && yellow.offsetLeft<=redDiv.offsetLeft+redDiv.offsetWidth){
console.log("碰到我了");
}
}
}
yellow.onmouseup = function () {
document.onmousemove= function () {
}
}
</script>
</html>
