var AbstractMap = {};

AbstractMap.Events = {
    getWheelEventDirection : function(event)
    {
        var delta = 0;
	    if (!event){
	        event = window.event;
	    }
	    if (event.wheelDelta) {
		    delta = event.wheelDelta/120;
		    if (window.opera){
		        delta = -delta;
		    }
	    } else if (event.detail) {
		    delta = -event.detail/3;
	    }
	    if (event.preventDefault){
            event.preventDefault();
        }
        event.returnValue = false;
        
        //delta is < 0 if zoom out. Otherwise zoom in. 
        return (delta<0)?1:-1;
    }
};