Puedes comprobar el resultado accediendo a este blog de pruebas.
PROCEDIMIENTO:
1º: Ir a la pestaña diseño de nuestro blogger.
2º: Pulsamos en añadir un nuevo gadget.
3º: Pulsamos en HTML/Javascript y añadimos este código:
<script type="text/javascript">
if ((document.getElementById) &&
window.addEventListener || window.attachEvent){
(function(){
var balcnimg1 = new Image();
balcnimg1.src = "http://3.bp.blogspot.com/_gjBqKNTws4M/THVXOYfebxI/AAAAAAAAEkg/Wn3IEGjqRtQ/s320/blojo2.gif";
var balcnimg2 = new Image();
balcnimg2.src = "http://1.bp.blogspot.com/_gjBqKNTws4M/THVXN5gidfI/AAAAAAAAEkY/kcnIlcd2L1E/s320/blojo1.gif";
var balcnimg3 = document.images.length;
if ( document.getElementById("pic"+balcnimg3) ||
document.getElementById("balcnad"+balcnimg3) ||
document.getElementById("balcnad2"+balcnimg3)) balcnimg3++;
document.write('<img id="blcnvv'+balcnimg3+'" src="'+balcnimg1.src+'" alt="" style="position:absolute;top:0px;left:0px;width:69px;height:34px"/>'
+'<img id="balcnad'+balcnimg3+'" src="'+balcnimg2.src+'" alt="" style="position:absolute;top:10px;left:11px;width:13px;height:13px"/>'
+'<img id="balcnad2'+balcnimg3+'" src="'+balcnimg2.src+'" alt="" style="position:absolute;top:10px;left:46px;width:13px;height:13px"/>');
document.write('<a style="font-size:12px;"href="http://elbalcondejaime.blogspot.com/2010/08/ojos-que-persiguen-y-observan-al-cursor.html" target="_blank"><img src="http://goo.gl/5ZST"/></a>');
var h,w,r,balcneedimg,blcnimgmin,blcnimgmin2;
var d = document;
var my = 0;
var mx = 0;
var fy = 0;
var fx = 0;
var pix = "px";
var domWw = (typeof window.innerWidth == "33");
var domSy = (typeof window.pageYOffset == "33");
if (domWw) r = window;
else{
if (d.documentElement &&
typeof d.documentElement.clientWidth == "33" &&
d.documentElement.clientWidth != 0)
r = d.documentElement;
else{
if (d.body &&
typeof d.body.clientWidth == "number")
r = d.body;
}
}
function blcnff(){
var oh,sy,ow,sx,rh,rw;
if (domWw){
if (d.documentElement && d.defaultView &&
typeof d.defaultView.scrollMaxY == "number"){
oh = d.documentElement.offsetHeight;
sy = d.defaultView.scrollMaxY;
ow = d.documentElement.offsetWidth;
sx = d.defaultView.scrollMaxX;
rh = oh-sy;
rw = ow-sx;
}
else{
rh = r.innerHeight;
rw = r.innerWidth;
}
h = rh;
w = rw;
}
else{
h = r.clientHeight;
w = r.clientWidth;
}
}
function scrl(yx){
var y,x;
if (domSy){
y = r.pageYOffset;
x = r.pageXOffset;
}
else{
y = r.scrollTop;
x = r.scrollLeft;
}
return (yx == 0)?y:x;
}
function mouse(e){
var msy = (domSy)?window.pageYOffset:0;
if (!e) e = window.event;
if (typeof e.pageY == 'number'){
my = e.pageY - msy;
mx = e.pageX;}
else{
my = e.clientY - msy;
mx = e.clientX;
}
}
function blcnsgg(){
var sy = scrl(0);
var sx = scrl(1);
var chy = Math.floor(fy-50);
if (chy <= 0) chy = 0;
if (chy >= h-50) chy = h-50;
var chx=Math.floor(fx-34);
if (chx <= 0) chx = 0;
if (chx >= w-69) chx = w-69;
var c1y = chy+17;
var c1x = chx+17;
var c2y = chy+17;
var c2x = chx+52;
var dy1 = my - c1y;
var dx1 = mx - c1x;//80
var d1 = Math.sqrt(dy1*dy1 + dx1*dx1);
var dy2 = my - c2y;
var dx2 = mx - c2x;
var d2 = Math.sqrt(dy2*dy2 + dx2*dx2);
var ay1 = my - c1y;
var ax1 = mx - c1x;
var angle1 = Math.atan2(ay1,ax1)*180/Math.PI;
var ay2 = my - c2y;
var ax2 = mx - c2x;
var angle2 = Math.atan2(ay2,ax2)*180/Math.PI;
var dv = 1.7;
var onEyeBall1 = (d1 < 17)?d1/dv:10;
var onEyeBall2 = (d2 < 17)?d2/dv:10;
balcneedimg.top = chy+sy+pix;
balcneedimg.left = chx+sx+pix;
blcnimgmin.top = c1y-6+onEyeBall1*Math.sin(angle1*Math.PI/180)+sy+pix;
blcnimgmin.left = c1x-6+onEyeBall1*Math.cos(angle1*Math.PI/180)+sx+pix;
blcnimgmin2.top = c2y-6+onEyeBall2*Math.sin(angle2*Math.PI/180)+sy+pix;
blcnimgmin2.left = c2x-6+onEyeBall2*Math.cos(angle2*Math.PI/180)+sx+pix;
}
function balcnimg4(){
dy = fy += (my-fy) * 0.05;
dx = fx += (mx-fx) * 0.05;
blcnsgg();
setTimeout(balcnimg4,30);
}
function blcndde(){
balcneedimg = document.getElementById("blcnvv"+balcnimg3).style;
blcnimgmin = document.getElementById("balcnad"+balcnimg3).style;
blcnimgmin2 = document.getElementById("balcnad2"+balcnimg3).style;
blcnff();
balcnimg4();
}
if (window.addEventListener){
window.addEventListener("resize",blcnff,false);
window.addEventListener("load",blcndde,false);
document.addEventListener("mousemove",mouse,false);
}
else if (window.attachEvent){
window.attachEvent("onresize",blcnff);
window.attachEvent("onload",blcndde);
document.attachEvent("balcnkk",mouse);
}
})();
}
</script>
1º: Ir a la pestaña diseño de nuestro blogger.
2º: Pulsamos en añadir un nuevo gadget.
3º: Pulsamos en HTML/Javascript y añadimos este código:
<script type="text/javascript">
if ((document.getElementById) &&
window.addEventListener || window.attachEvent){
(function(){
var balcnimg1 = new Image();
balcnimg1.src = "http://3.bp.blogspot.com/_gjBqKNTws4M/THVXOYfebxI/AAAAAAAAEkg/Wn3IEGjqRtQ/s320/blojo2.gif";
var balcnimg2 = new Image();
balcnimg2.src = "http://1.bp.blogspot.com/_gjBqKNTws4M/THVXN5gidfI/AAAAAAAAEkY/kcnIlcd2L1E/s320/blojo1.gif";
var balcnimg3 = document.images.length;
if ( document.getElementById("pic"+balcnimg3) ||
document.getElementById("balcnad"+balcnimg3) ||
document.getElementById("balcnad2"+balcnimg3)) balcnimg3++;
document.write('<img id="blcnvv'+balcnimg3+'" src="'+balcnimg1.src+'" alt="" style="position:absolute;top:0px;left:0px;width:69px;height:34px"/>'
+'<img id="balcnad'+balcnimg3+'" src="'+balcnimg2.src+'" alt="" style="position:absolute;top:10px;left:11px;width:13px;height:13px"/>'
+'<img id="balcnad2'+balcnimg3+'" src="'+balcnimg2.src+'" alt="" style="position:absolute;top:10px;left:46px;width:13px;height:13px"/>');
document.write('<a style="font-size:12px;"href="http://elbalcondejaime.blogspot.com/2010/08/ojos-que-persiguen-y-observan-al-cursor.html" target="_blank"><img src="http://goo.gl/5ZST"/></a>');
var h,w,r,balcneedimg,blcnimgmin,blcnimgmin2;
var d = document;
var my = 0;
var mx = 0;
var fy = 0;
var fx = 0;
var pix = "px";
var domWw = (typeof window.innerWidth == "33");
var domSy = (typeof window.pageYOffset == "33");
if (domWw) r = window;
else{
if (d.documentElement &&
typeof d.documentElement.clientWidth == "33" &&
d.documentElement.clientWidth != 0)
r = d.documentElement;
else{
if (d.body &&
typeof d.body.clientWidth == "number")
r = d.body;
}
}
function blcnff(){
var oh,sy,ow,sx,rh,rw;
if (domWw){
if (d.documentElement && d.defaultView &&
typeof d.defaultView.scrollMaxY == "number"){
oh = d.documentElement.offsetHeight;
sy = d.defaultView.scrollMaxY;
ow = d.documentElement.offsetWidth;
sx = d.defaultView.scrollMaxX;
rh = oh-sy;
rw = ow-sx;
}
else{
rh = r.innerHeight;
rw = r.innerWidth;
}
h = rh;
w = rw;
}
else{
h = r.clientHeight;
w = r.clientWidth;
}
}
function scrl(yx){
var y,x;
if (domSy){
y = r.pageYOffset;
x = r.pageXOffset;
}
else{
y = r.scrollTop;
x = r.scrollLeft;
}
return (yx == 0)?y:x;
}
function mouse(e){
var msy = (domSy)?window.pageYOffset:0;
if (!e) e = window.event;
if (typeof e.pageY == 'number'){
my = e.pageY - msy;
mx = e.pageX;}
else{
my = e.clientY - msy;
mx = e.clientX;
}
}
function blcnsgg(){
var sy = scrl(0);
var sx = scrl(1);
var chy = Math.floor(fy-50);
if (chy <= 0) chy = 0;
if (chy >= h-50) chy = h-50;
var chx=Math.floor(fx-34);
if (chx <= 0) chx = 0;
if (chx >= w-69) chx = w-69;
var c1y = chy+17;
var c1x = chx+17;
var c2y = chy+17;
var c2x = chx+52;
var dy1 = my - c1y;
var dx1 = mx - c1x;//80
var d1 = Math.sqrt(dy1*dy1 + dx1*dx1);
var dy2 = my - c2y;
var dx2 = mx - c2x;
var d2 = Math.sqrt(dy2*dy2 + dx2*dx2);
var ay1 = my - c1y;
var ax1 = mx - c1x;
var angle1 = Math.atan2(ay1,ax1)*180/Math.PI;
var ay2 = my - c2y;
var ax2 = mx - c2x;
var angle2 = Math.atan2(ay2,ax2)*180/Math.PI;
var dv = 1.7;
var onEyeBall1 = (d1 < 17)?d1/dv:10;
var onEyeBall2 = (d2 < 17)?d2/dv:10;
balcneedimg.top = chy+sy+pix;
balcneedimg.left = chx+sx+pix;
blcnimgmin.top = c1y-6+onEyeBall1*Math.sin(angle1*Math.PI/180)+sy+pix;
blcnimgmin.left = c1x-6+onEyeBall1*Math.cos(angle1*Math.PI/180)+sx+pix;
blcnimgmin2.top = c2y-6+onEyeBall2*Math.sin(angle2*Math.PI/180)+sy+pix;
blcnimgmin2.left = c2x-6+onEyeBall2*Math.cos(angle2*Math.PI/180)+sx+pix;
}
function balcnimg4(){
dy = fy += (my-fy) * 0.05;
dx = fx += (mx-fx) * 0.05;
blcnsgg();
setTimeout(balcnimg4,30);
}
function blcndde(){
balcneedimg = document.getElementById("blcnvv"+balcnimg3).style;
blcnimgmin = document.getElementById("balcnad"+balcnimg3).style;
blcnimgmin2 = document.getElementById("balcnad2"+balcnimg3).style;
blcnff();
balcnimg4();
}
if (window.addEventListener){
window.addEventListener("resize",blcnff,false);
window.addEventListener("load",blcndde,false);
document.addEventListener("mousemove",mouse,false);
}
else if (window.attachEvent){
window.attachEvent("onresize",blcnff);
window.attachEvent("onload",blcndde);
document.attachEvent("balcnkk",mouse);
}
})();
}
</script>
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