修改function snowIE()
{
for (i = 0; i < no; ++ i)
{
if (yp[i] < doc_height-50)
{
yp[i] += sty[i];
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]);
}else
{
document.all["dot"+i].style.visibility = 'hidden';
}
}
setTimeout("snowIE()", 20);
}
{
for (i = 0; i < no; ++ i)
{
if (yp[i] < doc_height-50)
{
yp[i] += sty[i];
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]);
}else
{
document.all["dot"+i].style.visibility = 'hidden';
}
}
setTimeout("snowIE()", 20);
}
1.找到 var no = 10; 改为 var no = 12;
2.修改下面的两个函数: 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) {
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()", 10);
} 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) {
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()", 20);
}
var no = 10; 函数snowNS()和snowIE()中的
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;
.....
}
使到底的雪花回到顶上,注释掉就可满足你的要求