/***************** effets de survol sur les images ***************/
var ImgRollOver = function(){
	this.images = new Array(); // tableau des images
	for(var i=0; i < arguments.length; i++){
		this.images[i] = {'img':document.getElementById(arguments[i][0]),'srcOut':document.getElementById(arguments[i][0]).src,'srcOver':arguments[i][1]};
	}
	this.preload();
	this.defineEvents();
}

// preload des images
ImgRollOver.prototype.preload = function(){
	var imgPreload = new Array();
	for(var i=0; i < this.images.length; i++){
		imgPreload[i] = new Image();
		imgPreload[i].src = this.images[i]['srcOver'];
	}
}

// définition des évènements de souris
ImgRollOver.prototype.defineEvents = function(){
	var self = this;
	for(var i=0; i < this.images.length; i++){
		if(this.images[i]['img'].addEventListener){
			this.images[i]['img'].addEventListener('mouseover',function(e){self.eventOver(e)},false);
			this.images[i]['img'].addEventListener('mouseout',function(e){self.eventOut(e)},false);
		}else{
			this.images[i]['img'].attachEvent('onmouseover',function(e){self.eventOver(e)});
			this.images[i]['img'].attachEvent('onmouseout',function(e){self.eventOut(e)});
		}
	}
}

// changement au survol
ImgRollOver.prototype.eventOver = function(e){
	if(e.currentTarget) var img = e.currentTarget;
	else var img = e.srcElement;
	for(var i=0; i < this.images.length; i++){
		if(this.images[i]['img'] == img){
			img.src = this.images[i]['srcOver'];
			break;
		}
	}
}

// changement à la perte du survol
ImgRollOver.prototype.eventOut = function(e){
	if(e.currentTarget) var img = e.currentTarget;
	else var img = e.srcElement;
	for(var i=0; i < this.images.length; i++){
		if(this.images[i]['img'] == img){
			img.src = this.images[i]['srcOut'];
			break;
		}
	}
}