window.addEvent('domready',function(){
	  /* settings */
	  var showDuration = 6000;
	  var container = $('div_contenant_slider');
	  var images = container.getElements('span');
	  var currentIndex = 0;
	  var interval;
	  /* opacity and fade */
	  images.each(function(img,i){ 
	    if (i > 0) {
	      img.set('opacity', 0);
		  img.set('visibility', 'visible');
	    }
	  });
	  /* worker */
	  var show = function() {
	    images[currentIndex].fade('out');
	    images[currentIndex = currentIndex < images.length - 1 ? currentIndex+1 : 0].fade('in');
	  };
	  /* start once the page is finished loading */
	  //window.addEvent('load',function(){
	    interval = show.periodical(showDuration);
	  //});


        var totIncrement = 0;
        var increment = 220;
        var nbAffiche = 4;
        var tot = $('zone_partenariat').getElements(".div_partenariat");
        var nbTotal = tot.length;
	var maxRightIncrement = increment*(-(nbTotal - nbAffiche));

        // Effet sur les news
        var fx = new Fx.Tween('zone_partenariat', {
            duration: 1000,
            wait: true
            //transition: Fx.Transitions.Back.easeInOut
	});

        //-------------------------------------
        // EVENTS for the button "previous"
        $('bt_prec').addEvent('click', function(event) {
            if(totIncrement<0) {
                var posActu = totIncrement;
                totIncrement = totIncrement + increment;
                fx.cancel();
                fx.start('margin-left', posActu, totIncrement);
            }
        });

        //-------------------------------------
        // EVENTS for the button "next"
        $('bt_next').addEvent('click', function(event) {
            if (totIncrement>maxRightIncrement) {
                var posActu = totIncrement;
                totIncrement = totIncrement - increment;
                fx.cancel();
                fx.start('margin-left', posActu, totIncrement);
            }
        });

});