Effet neige a l'invers

Bonjour,

Comment le sujet le dit si bien je cherche un javascript qui fasse un effet boules dans un verre de cola.
Je me suis dit que il faudré changer les parametres de l'effet neige pour que les images monten au liu de desendre, mais je suis nul dans javascript (niveux = premiere page du livre javascript pour lers nuls  ) et je me demande si un de vous pouvé m'aider.
Voici le script que j'ai pour l'effet neige:

<script LANGUAGE="JavaScript1.2">
<!-- Original:  Altan (snow@altan.hr) -->
<!-- Web Site:  [ Lien ] -->

<!-- This script and many more are available free online at -->
<!-- The JavaScript Source!! [ Lien ] -->

<!-- Begin
var no = 25; // snow number
var speed = 10; // smaller number moves the snow faster
var snowflake = "snow.gif";

var ns4up = (document.layers) ? 1 : 0;  // browser sniffer
var ie4up = (document.all) ? 1 : 0;
var dx, xp, yp;    // coordinate and position variables
var am, stx, sty;  // amplitude and step variables
var i, doc_width = 800, doc_height = 600;
if (ns4up) {
doc_width = self.innerWidth;
doc_height = self.innerHeight;
} else if (ie4up) {
doc_width = document.body.clientWidth;
doc_height = document.body.clientHeight;
}
dx = new Array();
xp = new Array();
yp = new Array();
am = new Array();
stx = new Array();
sty = new Array();
for (i = 0; i < no; ++ i) { 
dx[i] = 0;                        // set coordinate variables
xp[i] = Math.random()*(doc_width-50);  // set position variables
yp[i] = Math.random()*doc_height;
am[i] = Math.random()*20;         // set amplitude variables
stx[i] = 0.02 + Math.random()/10; // set step variables
sty[i] = 0.7 + Math.random();     // set step variables
if (ns4up) {                      // set layers
if (i == 0) {
document.write("<layer name=\"dot"+ i +"\" left=\"15\" ");
document.write("top=\"15\" visibility=\"show\"><img src=\"");
document.write(snowflake + "\" border=\"0\"></layer>");
} else {
document.write("<layer name=\"dot"+ i +"\" left=\"15\" ");
document.write("top=\"15\" visibility=\"show\"><img src=\"");
document.write(snowflake + "\" border=\"0\"></layer>");
   }
} else if (ie4up) {
if (i == 0) {
document.write("<div id=\"dot"+ i +"\" style=\"POSITION: ");
document.write("absolute; Z-INDEX: "+ i +"; VISIBILITY: ");
document.write("visible; TOP: 15px; LEFT: 15px;\"><img src=\"");
document.write(snowflake + "\" border=\"0\"></div>");
} else {
document.write("<div id=\"dot"+ i +"\" style=\"POSITION: ");
document.write("absolute; Z-INDEX: "+ i +"; VISIBILITY: ");
document.write("visible; TOP: 15px; LEFT: 15px;\"><img src=\"");
document.write(snowflake + "\" border=\"0\"></div>");
      }
   }
}
function snowNS() {  // Netscape main animation function
for (i = 0; i < no; ++ i) {  // iterate for every dot
yp[i] += sty[i];
if (yp[i] > doc_height-50) {
xp[i] = Math.random()*(doc_width-am[i]-30);
yp[i] = 0;
stx[i] = 0.02 + Math.random()/10;
sty[i] = 0.7 + Math.random();
doc_width = self.innerWidth;
doc_height = self.innerHeight;
}
dx[i] += stx[i];
document.layers["dot"+i].top = yp[i];
document.layers["dot"+i].left = xp[i] + am[i]*Math.sin(dx[i]);
}
setTimeout("snowNS()", speed);
}
function snowIE() {  // IE main animation function
for (i = 0; i < no; ++ i) {  // iterate for every dot
yp[i] += sty[i];
if (yp[i] > doc_height-50) {
xp[i] = Math.random()*(doc_width-am[i]-30);
yp[i] = 0;
stx[i] = 0.02 + Math.random()/10;
sty[i] = 0.7 + Math.random();
doc_width = document.body.clientWidth;
doc_height = document.body.clientHeight;
}
dx[i] += stx[i];
document.all["dot"+i].style.pixelTop = yp[i];
document.all["dot"+i].style.pixelLeft = xp[i] + am[i]*Math.sin(dx[i]);
}
setTimeout("snowIE()", speed);
}
if (ns4up) {
snowNS();
} else if (ie4up) {
snowIE();
}
// End -->
</script>

Merci pour votre aide
@+
Nazca