stringToCoords = function(raw) {
		if (typeof(raw) !== "string") $.error("String expected.");
		var split = raw.split('x');
		if (split.length !== 2) $.error("Should be two elements only.");

		var list = [];
		$.each(split, function() {
			var digit = Number($.trim(this));
			if (isNaN(digit)) $.error(this + " is not a digit.");
			list.push(digit);
		});

		return list;
	}
Convert a string with two digits, separated by x, into an array with two
values. Ie. "123x456" becomes [123,456]