function initRollOverImages() {
  var image_cache = new Object();
  $("img.swap").each(function(i) {
    var imgsrc = this.src;
    var dot = this.src.lastIndexOf('.');
    var imgsrc_on = this.src.substr(0, dot) + '_on' + this.src.substr(dot, 4);
    image_cache[this.src] = new Image();
    image_cache[this.src].src = imgsrc_on;
    $(this).hover(
      function() { this.src = imgsrc_on; },
      function() { this.src = imgsrc; });
  });
}

$(document).ready(initRollOverImages);

$(function() {
	if(document.URL.match("hot-spring.html")) {
		$("#navi1").attr("src","/images/navi1_on.jpg");
		$("#navi1").mouseout(function(){this.src = "/images/navi1_on.jpg";});
	} else if(document.URL.match("/restaurant/")) {
		$("#navi3").attr("src","/images/navi3_on.jpg");
		$("#navi3").mouseout(function(){this.src = "/images/navi3_on.jpg";});
	} else if(document.URL.match("/nature/")) {
		$("#navi5").attr("src","/images/navi5_on.jpg");
		$("#navi5").mouseout(function(){this.src = "/images/navi5_on.jpg";});
	} else if(document.URL.match("staying.html")) {
		$("#navi2").attr("src","/images/navi2_on.jpg");
		$("#navi2").mouseout(function(){this.src = "/images/navi2_on.jpg";});
	} else if(document.URL.match("/facilities/")) {
		$("#navi4").attr("src","/images/navi4_on.jpg");
		$("#navi4").mouseout(function(){this.src = "/images/navi4_on.jpg";});
	} else if(document.URL.match("art.html")) {
		$("#navi6").attr("src","/images/navi6_on.jpg");
		$("#navi6").mouseout(function(){this.src = "/images/navi6_on.jpg";});
	} else {
		$("#logo").attr("src","/images/logo_on.jpg");
		$("#logo").mouseout(function(){this.src = "/images/logo_on.jpg";});
	};
});