var id = -1;
var positive = true;
var timerDefilement;
var tempo;
var speed = 2;
var speedChangePic = 2;
var show = true;

function reinitialise(pic){
	document.getElementById(pic).style.opacity = 0; 
	document.getElementById(pic).style.filter = 'alpha(opacity=0)'; 
	document.getElementById(pic).style.MozOpacity = 0;
	document.getElementById(pic).style.display = 'block';
	show = true;
}

function defile(){
	if(positive) ++id 
	else --id;
	if(!document.getElementById('marque'+id)) {
		if(positive) id = 0;
		else id = nbTot-1;
	}
	reinitialise('marque'+id);
	timerOpacity('marque'+id);
}

function timerOpacity(pic){
	timerDefilement = setInterval("changeOpacity('"+pic+"')", speed*10);
}

function changeOpacity(pic){
 	if((parseFloat(document.getElementById(pic).style.MozOpacity) >= 1 || parseFloat(document.getElementById(pic).style.opacity) >= 1) && show == true) {
		document.getElementById(pic).style.opacity = 1; 
		document.getElementById(pic).style.filter = 'alpha(opacity=100)'; 
		document.getElementById(pic).style.MozOpacity = 1;
		show = false;
		clearInterval(timerDefilement);
		tempo = setTimeout("timerOpacity('"+pic+"')", speedChangePic*1000);
		return;
	}
	else if ((parseFloat(document.getElementById(pic).style.MozOpacity) <= 0 || parseFloat(document.getElementById(pic).style.opacity) <= 0) && show == false) {
		clearInterval(timerDefilement);
		tempo = setTimeout("document.getElementById('"+pic+"').style.display = 'none';", speedChangePic*20);
		timerDefilement = setTimeout("defile()", speedChangePic*20);
		return;
	}
	var modif = 0;
	if(show==false) modif = -1;
	else modif = 1;
	document.getElementById(pic).style.opacity = parseFloat(document.getElementById(pic).style.opacity) + ((speed/100)*modif); 
	document.getElementById(pic).style.filter = 'alpha(opacity='+parseFloat(document.getElementById(pic).style.opacity) * 100 +')'; 
	document.getElementById(pic).style.MozOpacity = parseFloat(document.getElementById(pic).style.MozOpacity) + ((speed/100)*modif);
}

function nextPic() {
	clearInterval(timerDefilement);	
	clearTimeout(tempo);
	document.getElementById('marque'+id).style.display = 'none';
	if(!document.getElementById('marque'+(id+1))) id = -1;
	positive = true;
	setTimeout("defile()", speedChangePic*20);
	return false;
}

function lastPic() {
	clearInterval(timerDefilement);	
	clearTimeout(tempo);
	document.getElementById('marque'+id).style.display = 'none';
	if(!document.getElementById('marque'+(id-1))) id = nbTot;
	positive = false;
	setTimeout("defile()", speedChangePic*20);
	return false;
}