var dragging = null;
$(document).ready(function () {
	$(document).mousemove(function (event) {
		if (dragging)
		{
			var offset = $(dragging).offset();
			var state = ((event.pageX-offset.left<$(dragging).width()/2)?0:1)+((event.pageY-offset.top<$(dragging).height()/2)?0:2);
			$(dragging).css("background-position","-"+($(dragging).width()*state)+"px 0px");
		}
		event.preventDefault();
	});
	$(".preview").mousedown(function (event) {
		if (event.which == 1)
		{
			event.preventDefault();
			dragging = this;
		}
	});
	$(document).mouseup(function (event) {
		if (event.which == 1)
		{
			dragging = null;
		}
	});
	$(".rotateHelp").show();
});