//=======================================================================
// over_img.js
//
// Universal version.
//
//=======================================================================

var oiBuf=null;
var oiCap=false;
var oiInitDone = false;
function oiPreload(){
  oiRegister('menu01','images/menu01-back-normal.png','images/menu01-back-hover.png');
  oiRegister('menu02','images/menu02-back-normal.png','images/menu02-back-hover.png');
  oiRegister('menu03','images/menu03-back-normal.png','images/menu03-back-hover.png');
}
function oiInit()
{
  var browserName=navigator.appName;
  var browserVersion=parseInt(navigator.appVersion);

  oiCap=
    (browserName.indexOf("Netscape")>=0 && browserVersion>=3) ||
    (browserName.indexOf("Internet Explorer")>=0 && browserVersion>=4);
    oiInitDone=true;
}

function oiIsCapability()
{
  if (!oiInitDone) oiInit();
  return oiCap;
}

function oiRegister(id,normalSrc,overSrc,downSrc)
{
  if (!oiInitDone) oiInit();

  if (oiCap)
  {
    if (overSrc==null)   overSrc=normalSrc;
    if (downSrc==null)   downSrc=overSrc;

    oiBuf=new Array(id,true,new Image(),new Image(),new Image());
    oiBuf[2].src=normalSrc;
    oiBuf[3].src=overSrc;
    oiBuf[4].src=downSrc;
    eval("oiObj"+id+"=oiBuf");
  }
}

function oiSetNormal(id,msg)
{
  if (oiCap)
  {
    var regObj=eval("oiObj"+id);
    if (regObj[1])
      document[id].src=regObj[2].src;
  }
  window.status=msg;
}

function oiSetOver(id,msg)
{
	window.status=msg;
  if (oiCap)
  {
    var regObj=eval("oiObj"+id);
    if (regObj[1])
      document[id].src=regObj[3].src;
  }
  return true;
}

function oiSetDown(id)
{
  if (oiCap)
  {
    var regObj=eval("oiObj"+id);
    if (regObj[1])
      document[id].src=regObj[4].src;
  }
}

function oiLock(id)
{
  if (oiCap)
    eval("oiObj"+id)[1]=false;
}

function oiUnlock(id)
{
  if (oiCap)
    eval("oiObj"+id)[1]=true;
}