This article describes the method of JavaScript to simulate parabolic motion under gravity state. Share it for your reference. The specific analysis is as follows:
This JavaScript code simulates parabola movement in gravity state, and can set the following parameters: horizontal initial velocity, longitudinal initial velocity, gravity acceleration (if this acceleration is a value that changes with time, other non-uniform acceleration movement can be achieved), animation interval time, etc.
<!doctype html>
<html>
<head>
<title>jsParabolic motion</title>
<meta charset="utf-8" />
<style type="text/css">
*{padding:0;margin:0;}
body{font-size:13px;padding:10px;}
p{margin:2px;}
.wrap{position:relative;width:1000px;height:550px;margin:0 auto;border:1px solid #ccc;margin-top:50px;}
#fall{width:20px;font-size:1px;height:20px;background:#000;position:absolute;top:0;left:0;}
</style>
</head>
<body>
<h3>模拟重力状态下的Parabolic motion（if1px==1mm）</h3>
<p>Horizontal initial speed：<input type="text" value="2" />px/ms</p>
<p>Longitudinal initial velocity：<input type="text" value="-2" />px/ms</p>
<p>Gravity acceleration：<input type="text" value="0.0098" />px/squarems</p>
<p>（If this acceleration is a value that changes over time，It can achieve other non-uniform acceleration movement effects。）</p>
<p>Unit time：<input type="text" value="10" />（Record the time interval of movement）
<p><input type="button" value="Demo" onclick="demo(('Vx').value, ('Vy').value, ('a').value, ('t').value)"/></p>
<div class="wrap">
<div >o</div>
</div>
</body>
<script type="text/javascript">
function demo(x,y,a,t) {
var f=('fall');
var Vx=parseInt(x),
Vy=parseInt(y),
g=a,
t=parseInt(t),
h=0,l=0,Sx=0,Sy=0;
var i=setInterval(function(){
if(f){
Sx+=Vx*t;
l=Sx;
Vy+=g*t;
h+=Vy*t;
=l+'px';
=h+'px';
if(h>500||l>900)clearInterval(i);
}
},t);
}
</script>
</html>
I hope this article will be helpful to everyone's JavaScript programming.