// script di zer0 adattato all'abbisogno 
function setOpacity(el, fOp){
        if (typeof el.style!="undefined"){
                if ( typeof el.style.MozOpacity!="undefined" )
                        el.style.MozOpacity = fOp-0.001;
                else if ( typeof el.style.opacity!="undefined" )
                        el.style.opacity = fOp;
                else if ( typeof el.style.KhtmlOpacity != "undefined" )
                        el.style.KhtmlOpacity = fOp;
                else if ( typeof el.style.filter!="undefined"  )
                        el.style.filter = "Alpha(Opacity="+(fOp*100)+")";
        }
}

function mix(delay){
	var front_image=document.getElementById("front_img");
	var back_image=document.getElementById("backg_div");
	opacity-=step;
	
	if ( opacity < 0 || opacity > 1 ){
		opacity = Math.round(opacity);
		if (opacity == 0){
			imgs.index++;
			front_image.src = imgs[imgs.index].src;
			delay=100;
		}else{
			if (imgs.index==18){imgs.index=0};				
			back_image.setAttribute("style", "background:url("+imgs[imgs.index+1].src+") no-repeat;")
			delay = 2500;
		}
		step=-step;
	}else{
		delay = 50;
	}
	setTimeout(mix,delay);
	setOpacity(document.getElementById("front_img"),opacity);
}

window.onload = function(){mix(50)};


var i;
var imgs=[];
for(i=1;i<19;i++){
	imgs[i]= new Image;
	imgs[i].src="sliding_images/"+i+".jpg";
}
var opacity = 1, step = 0.06;
imgs.index=0;