<script type="text/javascript">
var speed=20; // A menor numero más rápido
var flakes=20; // Numero de Copos de Nieve
var flake_image="URL.gif"; // URL de la imagen de nieve
var swide, shigh;
var dx=new Array();
var xp=new Array();
var yp=new Array();
var am=new Array();
var sty=new Array();
window.onload=function() { if (document.getElementById) {
var k, f, b;
b=document.createElement("div");
b.style.position="absolute";
b.setAttribute("id", "bod");
document.body.appendChild(b);
set_scroll();
set_width();
for (var i=0; i<flakes; i++) {
dx[i]=0;
am[i]=Math.random()*20;
xp[i]=am[i]+Math.random()*(swide-2*am[i]-25);
yp[i]=Math.random()*shigh;
sty[i]=0.75+1.25*Math.random();
f=document.createElement("div");
f.style.position="absolute";
f.setAttribute("id", "flk"+i);
f.style.zIndex=i;
f.style.top=yp[i]+"px";
f.style.left=xp[i]+"px";
k=document.createElement("img");
k.src=flake_image;
f.appendChild(k);
b.appendChild(f);
}
setInterval("winter_snow()", speed);
}}
window.onresize=set_width;
function set_width() {
if (document.documentElement && document.documentElement.clientWidth) {
swide=document.documentElement.clientWidth;
shigh=document.documentElement.clientHeight;
}
else if (typeof(self.innerHeight)=="number") {
swide=self.innerWidth;
shigh=self.innerHeight;
}
else if (document.body.clientWidth) {
swide=document.body.clientWidth;
shigh=document.body.clientHeight;
}
else {
swide=800;
shigh=600
}
}
window.onscroll=set_scroll;
function set_scroll() {
var sleft, sdown;
if (typeof(self.pageYOffset)=="number") {
sdown=self.pageYOffset;
sleft=self.pageXOffset;
}
else if (document.body.scrollTop || document.body.scrollLeft) {
sdown=document.body.scrollTop;
sleft=document.body.scrollLeft;
}
else if (document.documentElement && (document.documentElement.scrollTop || document.documentElement.scrollLeft)) {
sleft=document.documentElement.scrollLeft;
sdown=document.documentElement.scrollTop;
}
else {
sdown=0;
sleft=0;
}
document.getElementById("bod").style.top=sdown+"px";
document.getElementById("bod").style.left=sleft+"px";
}
function winter_snow() {
for (var i=0; i<flakes; i++) {
yp[i]+=sty[i];
if (yp[i]>shigh-30) {
xp[i]=am[i]+Math.random()*(swide-2*am[i]-25);
yp[i]=0;
sty[i]=0.75+1.25*Math.random();
}
dx[i]+=0.02+Math.random()/10;
document.getElementById("flk"+i).style.top=yp[i]+"px";
document.getElementById("flk"+i).style.left=(xp[i]+am[i]*Math.sin(dx[i]))+"px";
}
}
</script>