/*
	Image Cross Fade Redux
	Version 1.0
	Last revision: 02.15.2006
	steve@slayeroffice.com

	Rewrite of old code found here: http://slayeroffice.com/code/imageCrossFade/index.html
*/

window.addEventListener?window.addEventListener('load',so_init,false):window.attachEvent('onload',so_init);

var d=document, imgs = new Array(), zInterval = null, current=0, pause=false,stilesheet;

function so_init()
{
	var tmpHeight=0
	if(!d.getElementById || !d.createElement)return;

/*	css = d.createElement('link');
	css.setAttribute('href','css/slideshow2.css');
	css.setAttribute('rel','stylesheet');
	css.setAttribute('type','text/css');
	d.getElementsByTagName('head')[0].appendChild(css);*/
	imgs = d.getElementById('slideshow').getElementsByTagName('img');
	for(i=1;i<imgs.length;i++){
	proporzionaImmagine(imgs[i],740,460); 
	tmpHeight=((460-(imgs[i].height))/2)
	imgs[i].style.marginTop=(tmpHeight+'px');
	imgs[i].style.marginBottom=(tmpHeight+'px');
	//alert(tmpHeight+'px')
	imgs[i].xOpacity = 0;
	};
	
	proporzionaImmagine(imgs[0],740,460)
	tmpHeight=((460-(imgs[0].height))/2)
	imgs[0].style.marginTop=(tmpHeight+'px');
	imgs[0].style.marginBottom=(tmpHeight+'px');
	imgs[0].style.display = 'block';
	imgs[0].xOpacity = .99;

	setTimeout(so_xfade,3000);
}

function so_xfade()
{
	cOpacity = imgs[current].xOpacity;
	nIndex = imgs[current+1]?current+1:0;
	nOpacity = imgs[nIndex].xOpacity;

	cOpacity-=.05;
	nOpacity+=.05;

	imgs[nIndex].style.display = 'block';
	imgs[current].xOpacity = cOpacity;
	imgs[nIndex].xOpacity = nOpacity;

	setOpacity(imgs[current]);
	setOpacity(imgs[nIndex]);

	if(cOpacity<=0)
	{
		imgs[current].style.display = 'none';
		current = nIndex;
		setTimeout(so_xfade,3000);
	}
	else
	{
		setTimeout(so_xfade,50);
	}

	function setOpacity(obj)
	{
		if(obj.xOpacity>.99)
		{
			obj.xOpacity = .99;
			return;
		}

		obj.style.opacity = obj.xOpacity;
		obj.style.MozOpacity = obj.xOpacity;
		obj.style.filter = 'alpha(opacity=' + (obj.xOpacity*100) + ')';
	}
}


function proporzionaImmagine(objImg,maxWidth,maxHeight){
	    var tmpWidth 
        var tmpHeight 
        var newHeight
        var newWidth
		
		

        tmpWidth = objImg.width
        tmpHeight = objImg.height

        //NUOVA PROPORZIONE IMMAGINE
        if( tmpWidth >= tmpHeight ){

            newWidth = maxWidth
            newHeight = (tmpHeight*newWidth)/tmpWidth
			
			if( newHeight > maxHeight ){
				newHeight=maxHeight
				newWidth = (tmpWidth*newHeight)/tmpHeight
			}
		}
        else{
            newHeight = maxHeight
            newWidth = (tmpWidth*newHeight)/tmpHeight
			
			if( newWidth > maxWidth ){
				newWidth=maxWidth
				newHeight = (tmpHeight*newWidth)/tmpWidth
			}
			
		}

		objImg.width=newWidth;
		objImg.height=newHeight;
		//alert(sd.width +" - " +sd.height)
	
	}