Next element when wheel is scrolling

// Author: Piotr Filipek
// Script: SoQ 4.0.0
 
$.Wheel = [];
$.e.wheel = function(a1, a2){
	var time = (new Date()).getTime()
	var a3 = 0;
 
	$.Wheel[time] = 0;
 
	$(this).on("mousewheel", function(e){
		if(e.wheel == 1){
			if($.Wheel[time] != a1.length-1) ++$.Wheel[time];
		} else {
			if($.Wheel[time] != 0) --$.Wheel[time];
		}
 
		a3 = $.Wheel[time]%a1.length;
		$.func(a2).call(this, a1, a3, a1[a3]);
	});
};
 
// Ex. 1 - font size
$("#size").wheel([15, 20, 25, 30], function(a1, a2){
	$(this).css("font-size", a1[a2]);
});
 
// Ex. 2 - colors
$("#color").wheel(["green", "red", "blue", "black"], function(a1, a2){
	$(this).css("background", a1[a2]);
});