var agent = navigator.userAgent;
var appver = navigator.appVersion;
var nav = navigator.appName;
var plf = null;
var ver = null;

if(agent.indexOf('Mac') != -1){
	plf = "Mac";
}else if(agent.indexOf('Win') != -1){
	plf = "Win";
}else{
	plf = "other";
}
if(agent.indexOf('MSIE') == -1){
	ver = appver.charAt(0);
	if(nav == "Netscape"){
		nav = "NN";
	}
}else{
	ver = agent.charAt(agent.indexOf('MSIE') + 5);
	nav = "MSIE";
}

var imageDir = "images/";
var loadList;
var action = "off";

function preLoad() {
    loadList = new Array( "m01_on.gif", "m01_a_on.gif", "m01_b_on.gif", "m01_c_on.gif", "m01_d_on.gif", "m02_on.gif", "m03_on.gif", "m04_on.gif", "m05_on.gif", "m06_on.gif", "m07_on.jpg","main_01.jpg", "main_02.jpg", "main_03.jpg", "main_04.jpg", "submenu01_on.gif", "submenu02_on.gif", "submenu03_on.gif", "submenu04_on.gif");
    onImages = new Array();
    for (field in loadList){
        onImages[field] = new Image();
        onImages[field].src = imageDir + loadList[field];
    }
    action = "on";
}

function changeImage1 (fileName, imageName, fileName2, imageName2, fileName3, imageName3) {
	if (action == "on") {
		document.images[imageName].src = imageDir + fileName;
		document.images[imageName2].src = imageDir + fileName2;
		document.images[imageName3].src = imageDir + fileName3;
	}
}

function changeImage2 (fileName, imageName) {
	if (action == "on") {
		document.images[imageName].src = imageDir + fileName;
	}
}

function changeImage3 (fileName, imageName, fileName2, imageName2) {
	if (action == "on") {
		document.images[imageName].src = imageDir + fileName;
		document.images[imageName2].src = imageDir + fileName2;
	}
}