// pas touche
var indice = 2; // les 2 premiere image sont deja charger dans le HTML, on commence a la 3eme
var isIE = navigator.userAgent.toLowerCase().indexOf('msie')!=-1 ;
var img1 = null;
var img2 = null ;
var sens = 0;
var tabImg; // tab contenant les images

window.setTimeout("init()", temps_pause) ; // recursion toutes les x millisec

function prechargerImg() {
	tabImg = new Array(nombre_image);
	for (i=0; i<=nombre_image -1; i++){
		tabImg[i]=new Image();
		tabImg[i].src = prefix_image+(i+1)+suffix_image;
	}
}

function init() {
	img1 = document.getElementById("defilement1") ;
	img2 = document.getElementById("defilement2") ;
	
	prechargerImg();
	change_opacity();
}

function change_opacity() {
	var opacity1 = 0 ;
	var opacity2 = 0 ;
	if (isIE)	{ // for IE
		opacity1 = parseFloat(img1.filters.alpha.opacity);
		opacity2 = parseFloat(img2.filters.alpha.opacity);
	}
	else { // for mozilla
		opacity1 = parseFloat(img1.style.MozOpacity);
		opacity2 = parseFloat(img2.style.MozOpacity);
	}
	
	if (sens)	{
		if (isIE) { // for IE
			img1.filters.alpha.opacity = opacity1 + coef * 100;
			img2.filters.alpha.opacity = opacity2 - coef * 100;
		}
		else { // for Mozilla
			img1.style.MozOpacity = opacity1 + coef;
			img2.style.MozOpacity = opacity2 - coef;
		}
	}
	else {
		if (isIE) { // for IE
			img1.filters.alpha.opacity = opacity1 - coef * 100;
			img2.filters.alpha.opacity = opacity2 + coef * 100;
		}
		else { // for Mozilla
			img1.style.MozOpacity = opacity1 - coef;
			img2.style.MozOpacity = opacity2 + coef;
		}
	}
	
	if (isIE) { // for IE
		opacity1 = parseFloat(img1.filters.alpha.opacity);
		opacity2 = parseFloat(img2.filters.alpha.opacity);
	}
	else { // for mozilla
		opacity1 = parseFloat(img1.style.MozOpacity);
		opacity2 = parseFloat(img2.style.MozOpacity);
	}
	
	// on fait varié le sens d'opacité du bazar
	if (opacity2 <= 0) {
		img2.src=tabImg[indice++].src;
		sens = 0;
		if (indice == (tabImg.length)) indice=0;
		window.setTimeout("change_opacity()",temps_pause) ; // attente
		return 0;
	}
	else if (opacity1 <= 0)	{
		img1.src=tabImg[indice++].src;
		sens = 1;
		if (indice == (tabImg.length)) indice=0;
		window.setTimeout("change_opacity()",temps_pause) ; // attente
		return 0;
	}
	window.setTimeout("change_opacity()",temps) ; // recursion toutes les x millisec
}