//smooth scroll

fx.Scroll = Class.create();
fx.Scroll.prototype = Object.extend(new fx.Base(), {
	initialize: function(options) {
		this.setOptions(options);
	},

	scrollTo: function(el){
		var dest = Position.cumulativeOffset($(el))[1];
		var client = window.innerHeight || document.documentElement.clientHeight;
		var full = document.documentElement.scrollHeight;
		var top = window.pageYOffset || document.body.scrollTop || document.documentElement.scrollTop;
		if (dest+client > full) this.custom(top, dest - client + (full-dest));
		else this.custom(top, dest);
	},

	increase: function(){
		window.scrollTo(0, this.now);
	}
});


fx.sineOut = function(pos){
	return Math.sin(pos * (Math.PI/2));
}
fx.sineIn = function(pos){
	return -Math.cos(pos * (Math.PI/2)) + 1;
}
fx.sineInOut = function(pos){
	return -(Math.cos(Math.PI*pos) - 1)/2;
}