var nb_slides = 2; //number of slideshows to display (must be =, or > to the number of calls to this function)
	var AccelMax = 1;

	var pos = new Array(nb_slides);
	var acc = new Array(nb_slides);
	var maxG = new Array(nb_slides);
	for(i=0; i<nb_slides; i++)
	{
		pos[i] = 0;
		acc[i] = 0;
	}
	var deplacG;
	var deplacD;
	var depD=0, depG=0;
	var frein;
	var MaxDroite=0;
	var depPas=1;
	
	var Timer;
	var Pas = 3;

	function deplGauche(div)
	{
		depG=1;
		deplacerGauche(div);
		deplacG = window.setInterval("deplacerGauche("+div+")", 20);
	}

	function deplacerGauche(div)
	{
		position = pos[div];
		accel = acc[div]; 
		position = position - 500;
		/*if(accel<AccelMax) 
			accel++;*/
		document.getElementById("ruban"+div).style.left = position;
		if(position>=maxG[div]) 
		{
			document.getElementById('ruban'+div).style.left = position;
			document.getElementById('nav_gauche_'+div).style.visibility='visible';
		}
		else 
		{
			/*accel=0;*/
			document.getElementById('ruban'+div).style.left = maxG[div];
			position=maxG[div];
			clearInterval(deplacG);
			document.getElementById('nav_droite_'+div).style.visibility='hidden';
		}
		pos[div] = position;
		acc[div] = accel;
	}
	
	function deplDroite(div)
	{
		depD=1;
		deplacD = window.setInterval("deplacerDroite("+div+")", 20);
		
	}
	function deplacerDroite(div)
	{
		position = pos[div];
		accel = acc[div];
		position = position + 500;
		/*if(accel<AccelMax) 
			accel++;*/
		if(position<MaxDroite) 
		{
			document.getElementById('ruban'+div).style.left = position;
			document.getElementById('nav_droite_'+div).style.visibility='visible';
		}
		else 
		{
			/*accel=0;*/
			document.getElementById('ruban'+div).style.left = MaxDroite;
			position=MaxDroite;
			clearInterval(deplacD);
			document.getElementById('nav_gauche_'+div).style.visibility='hidden';
		}
		pos[div] = position;
		acc[div] = accel;
	}
	
	function freineGauche(div)
	{
		position = pos[div];
		accel = acc[div];
		position = position-accel;
		if(accel>0 && depG==0) 
			accel--;
		else 
		{
			clearInterval(frein);
		}
		if(position>maxG[div]) 
			document.getElementById('ruban'+div).style.left = position;
		pos[div] = position;
		acc[div] = accel;
	}	
	
	function freineDroite(div)
	{
		position = pos[div];
		accel = acc[div];
		position = position+accel;
		if(accel>0 && depD==0) 
			accel--;
		else 
		{
			clearInterval(frein);
		}
		if(position<MaxDroite) 
			document.getElementById('ruban'+div).style.left = position;
		pos[div] = position;
		acc[div] = accel;
	}	

	function arreter(sens, div)
	{
		clearInterval(deplacG);
		depG=0;
		clearInterval(deplacD);
		depD=0;
		frein = window.setInterval(sens+"("+div+")", 50);
		
	}