var leftToRight = 1; var rightToLeft = -1;

Effect.Slide = Class.create();
Object.extend(Object.extend(Effect.Slide.prototype, Effect.Move.prototype), {
	initialize: function(element) {
		this.element = $(element);
		if (arguments[1]) arguments[1].x = arguments[1].x * arguments[1].direction;

		var options = Object.extend({
			x:    0,
			y:    0,
			direction: rightToLeft,
			mode: 'relative',
			duration: 2,
			redirections : 1,
			transition: function(pos) { 
				pos = (- Math.cos(pos*Math.PI) / 2 + 0.5);
				pos = (- Math.cos(pos*Math.PI) / 2 + 0.5);
				var val = (- Math.cos(pos*Math.PI) / 2 + 0.5);
				return val; 
			}
		}, arguments[1] || {});

		this.start(options);
	},

	finish: function() {
	}
});