<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<title>3D效果的JS烟花背景特效丨www.update8.com</title>
</head>
<style type="text/css">
.fire{display:block; overflow:hidden; font-size:12px; position:absolute};
body{overflow:hidden; background:#000}
html{overflow:hidden; background:#000}
</style>
<body>
<div style="728px;margin:10px auto; overflow:hidden;">
<script type="text/javascript"><!--
google_ad_client = "ca-pub-6259241468270513";
/* 728*90 图片广告 */
google_ad_slot = "4067870451";
google_ad_width = 728;
google_ad_height = 90;
//-->
</script>
<script type="text/javascript"
src="http://pagead2.googlesyndication.com/pagead/show_ads.js">
</script>
</div>
</body>
<script type="text/javascript">
var Fire = function(r, color) {
this.radius = r || 12;
this.color = color || "FF6600";
this.xpos = 0;
this.ypos = 0;
this.zpos = 0;
this.vx = 0;
this.vy = 0;
this.vz = 0;
this.mass = 1;
this.p = document.createElement("span");
this.p.className = "fire";
this.p.innerHTML = "*";
this.p.style.fontSize = this.radius + "px";
this.p.style.color = "#" + this.color;
}
Fire.prototype = {
append: function(parent) {
parent.appendChild(this.p);
},
setSize: function(scale) {
this.p.style.fontSize = this.radius * scale + "px";
},
setPosition:function(x, y) {
this.p.style.left = x + "px";
this.p.style.top = y + "px";
},
setVisible: function(b) {
this.p.style.display = b ? "block" : "none";
}
}
var fireworks = function() {
var fires = new Array();
var count = 100;
var fl = 250;
var vpx = 500;
var vpy = 300;
var gravity = .3;
var floor = 200;
var bounce = -.8;
var timer;
return {
init: function() {
for (var i=0; i<count; i++) {
var color = 0xFF0000;
color = (Math.random() * 0xFFFFFF).toString(16).toString().split(".")[0];
while(color.length < 6) {
color = "0" + color;
}
var fire = new Fire(12, color);
fires.push(fire);
fire.ypos = -100;
fire.vx = Math.random() * 6 - 3;
fire.vy = Math.random() * 6 - 3;
fire.vz = Math.random() * 6 - 3;
fire.append(document.body);
}
var that = this;
timer = setInterval(function() {
for (var i=0;i<count; i++) {
that.move(fires[i]);
}
}, 30);
},
move: function(fire) {
fire.vy += gravity;
fire.xpos += fire.vx;
fire.ypos += fire.vy;
fire.zpos += fire.vz;
if (fire.ypos > floor) {
fire.ypos = floor;
fire.vy *= bounce;
}
if (fire.zpos > -fl) {
var scale = fl/ (fl+fire.zpos);
fire.setSize(scale);
fire.setPosition(vpx + fire.xpos * scale,
vpy + fire.ypos * scale);
fire.setVisible(true);
} else {
fire.setVisible(false);
}
}
}
}
fireworks().init();
</script>
</html>