var nImg=28;
var imgAct=new Array();
var destino=0;
var nueva=0;
function cambiaImg()
{
	destino=Math.floor(Math.random()*6);
	nueva=Math.floor(Math.random()*nImg);
	while (imgAct[0]==nueva || imgAct[1]==nueva || imgAct[2]==nueva || imgAct[3]==nueva || imgAct[4]==nueva || imgAct[5]==nueva)
	{
		nueva=Math.floor(Math.random()*nImg);
	}
	fadeOut('img'+destino,10,'cambiaImg2()');
}

function cambiaImg2()
{
	document.getElementById('img'+destino).src='img/fondos/'+nueva+'.jpg';
	imgAct[destino]=nueva;
	fadeIn('img'+destino,10,'cambiaImg3()');
}

function cambiaImg3()
{
	setTimeout('cambiaImg()',5000);
}

var ob=null;
var op=100;
var callback='';
var step=0;
var maxOp=100;

function fadeOut(id,val,call)
{
	op=maxOp;
	ob=document.getElementById(id);
	step=val;
	callback=call;
	setTimeout("hazFadeOut()",25);
}

function hazFadeOut()
{
	op-=step;
	if(op<=0)
	{
		K_trans(ob,0);
		ob.style.display='none';
		if(callback)
			eval(callback);
	}
	else
	{
		K_trans(ob,op);
		setTimeout("hazFadeOut()",25);
	}
}

function fadeIn(id,val,call)
{
	op=0;
	ob=document.getElementById(id);
	ob.style.display='block';
	step=val;
	callback=call;
	setTimeout("hazFadeIn()",25);
}

function hazFadeIn()
{
	op+=step;
	if(op>=maxOp)
	{
		K_trans(ob,maxOp);
		if(callback)
			eval(callback);
	}
	else
	{
		K_trans(ob,op);
		setTimeout("hazFadeIn()",25);
	}
}

function K_trans(obj,opacity)
//By Richard Rutter
{
 	opacity = (opacity == 100)?99.999:opacity;
  	obj.style.KhtmlOpacity = opacity/100;
  	obj.style.filter = "alpha(opacity:"+opacity+")";
  	obj.style.MozOpacity = opacity/100;
  	obj.style.opacity = opacity/100;
}