Primavera en el blog

Me comentaba Charo que le gustaría decorar su blog con algún efecto primaveral, me sugería un efecto como el que vemos en Navidades de copos cayendo por la página.

Recordé uno de Dynamic Drive con mariposas revoloteando y sustituí algunas mariposas por florecillas que es la idea que ella tiene.

Para añadirlo a nuestro blog nos situamos al final de la plantilla justo antes de </body> y añadimos lo siguiente:

<script language="JavaScript1.2">
//<![CDATA[
/*Flying Butterfly script (By BGAudioDr@aol.com)
Modified slightly/ permission granted to Dynamic Drive to feature script in archive
For full source, visit http://www.dynamicdrive.com */

var Ymax=8; //MAX # OF PIXEL STEPS IN THE "X" DIRECTION
var Xmax=8; //MAX # OF PIXEL STEPS IN THE "Y" DIRECTION
var Tmax=10000; //MAX # OF MILLISECONDS BETWEEN PARAMETER CHANGES

//FLOATING IMAGE URLS FOR EACH IMAGE. ADD OR DELETE ENTRIES. KEEP ELEMENT NUMERICAL ORDER STARTING WITH "0" !!

var floatimages=new Array();
floatimages[0]='url-imagen-mariposas';
floatimages[1]='url-imagen-flor';
floatimages[2]='url-imagen-hoja-verde';
floatimages[3]='url-imagen-mariposas';
floatimages[4]='url-imagen-flor';
floatimages[5]='url-imagen-hoja-verde';
floatimages[6]='url-imagen-flor';

//*********DO NOT EDIT BELOW***********
var NS4 = (navigator.appName.indexOf("Netscape")>=0 && parseFloat(navigator.appVersion) >= 4 && parseFloat(navigator.appVersion) < 5)? true : false;
var IE4 = (document.all)? true : false;
var NS6 = (parseFloat(navigator.appVersion) >= 5 && navigator.appName.indexOf("Netscape")>=0 )? true: false;
var wind_w, wind_h, t='', IDs=new Array();
for(i=0; i<floatimages.length; i++){
t+=(NS4)?'<layer name="pic'+i+'" visibility="hide" width="10" height="10"><a href="javascript:hidebutterfly()">' : '<div id="pic'+i+'" style="position:absolute; visibility:hidden;width:10px; height:10px">

<a href="javascript:hidebutterfly()">';
t+='<img src="'+floatimages[i]+'" name="p'+i+'" border="0">';
t+=(NS4)? '</a></layer>':'</a></div>
';
}
document.write(t);

function moveimage(num){
if(getidleft(num)+IDs[num].W+IDs[num].Xstep >= wind_w+getscrollx())IDs[num].Xdir=false;
if(getidleft(num)-IDs[num].Xstep<=getscrollx())IDs[num].Xdir=true;
if(getidtop(num)+IDs[num].H+IDs[num].Ystep >= wind_h+getscrolly())IDs[num].Ydir=false;
if(getidtop(num)-IDs[num].Ystep<=getscrolly())IDs[num].Ydir=true;
moveidby(num, (IDs[num].Xdir)? IDs[num].Xstep : -IDs[num].Xstep , (IDs[num].Ydir)? IDs[num].Ystep: -IDs[num].Ystep);
}

function getnewprops(num){
IDs[num].Ydir=Math.floor(Math.random()*2)>0;
IDs[num].Xdir=Math.floor(Math.random()*2)>0;
IDs[num].Ystep=Math.ceil(Math.random()*Ymax);
IDs[num].Xstep=Math.ceil(Math.random()*Xmax)
setTimeout('getnewprops('+num+')', Math.floor(Math.random()*Tmax));
}

function getscrollx(){
if(NS4 || NS6)return window.pageXOffset;
if(IE4)return document.body.scrollLeft;
}

function getscrolly(){
if(NS4 || NS6)return window.pageYOffset;
if(IE4)return document.body.scrollTop;
}

function getid(name){
if(NS4)return document.layers[name];
if(IE4)return document.all[name];
if(NS6)return document.getElementById(name);
}

function moveidto(num,x,y){
if(NS4)IDs[num].moveTo(x,y);
if(IE4 || NS6){
IDs[num].style.left=x+'px';
IDs[num].style.top=y+'px';
}}

function getidleft(num){
if(NS4)return IDs[num].left;
if(IE4 || NS6)return parseInt(IDs[num].style.left);
}

function getidtop(num){
if(NS4)return IDs[num].top;
if(IE4 || NS6)return parseInt(IDs[num].style.top);
}

function moveidby(num,dx,dy){
if(NS4)IDs[num].moveBy(dx, dy);
if(IE4 || NS6){
IDs[num].style.left=(getidleft(num)+dx)+'px';
IDs[num].style.top=(getidtop(num)+dy)+'px';
}}

function getwindowwidth(){
if(NS4 || NS6)return window.innerWidth;
if(IE4)return document.body.clientWidth;
}

function getwindowheight(){
if(NS4 || NS6)return window.innerHeight;
if(IE4)return document.body.clientHeight;
}

function init(){
wind_w=getwindowwidth();
wind_h=getwindowheight();
for(i=0; i<floatimages.length; i++){
IDs[i]=getid('pic'+i);
if(NS4){
IDs[i].W=IDs[i].document.images["p"+i].width;
IDs[i].H=IDs[i].document.images["p"+i].height;
}
if(NS6 || IE4){
IDs[i].W=document.images["p"+i].width;
IDs[i].H=document.images["p"+i].height;
}
getnewprops(i);
moveidto(i , Math.floor(Math.random()*(wind_w-IDs[i].W)), Math.floor(Math.random()*(wind_h-IDs[i].H)));
if(NS4)IDs[i].visibility = "show";
if(IE4 || NS6)IDs[i].style.visibility = "visible";
startfly=setInterval('moveimage('+i+')',Math.floor(Math.random()*100)+100);
}}

function hidebutterfly(){
for(i=0; i<floatimages.length; i++){
if (IE4)
eval("document.all.pic"+i+".style.visibility='hidden'")
else if (NS6)
document.getElementById("pic"+i).style.visibility='hidden'
else if (NS4)
eval("document.pic"+i+".visibility='hide'")
clearInterval(startfly)
}
}

if (NS4||NS6||IE4){
window.onload=init;
window.onresize=function(){ wind_w=getwindowwidth(); wind_h=getwindowheight(); }
}
//]]>
</script>

Las imágenes las debemos añadir donde dice "url-imagen-flor" "url-imagen-mariposa" "url-imagen-hoja-verde"

La mariposa al ser un gif si lo subimos a Blogger queda estática, pero podemos subirla a ImageShack y solucionamos el problema.

Provisionalmente se puede ver el resultado aquí.