var menuflag = 0;
 
var overImgs = new Array();
var outImgs = new Array();
var inImgs = new Array();
var options = new Array('logo','book','world','author','extras','buyhardcover','buylibrary','buypaperback','buyaudio','note','excerpt','story');

var imgPath = "img/nav/";
 
function LoadMenu () {
  var n;
  if ( document.images ) {  
    for ( n = 0; n < options.length; n++ ) {
      option_name = options[n];
      
      overImgs[option_name] = new Image(); overImgs[option_name].src = imgPath + option_name + "_on.gif";
      
      outImgs[option_name] = new Image(); outImgs[option_name].src = imgPath + option_name + "_off.gif";
	  
	  inImgs[option_name] = new Image(); inImgs[option_name].src = imgPath + option_name + "_in.gif";
    }
    
    menuflag = 1;
  }
}

// function to show "out" images on main menu 
function ShowOut ( name ) {
  if ( document.images ) {
    if ( menuflag ) {
      document.images[name].src = outImgs[name].src;
      
    }
  }
}

// function to show "over" images on menu
function ShowOver ( name ) {
  if ( document.images ) {
    if ( menuflag ) {
      document.images[name].src = overImgs[name].src;

    }
  }
}

// function to show "in" images on menu
function ShowIn ( name ) {
  if ( document.images ) {
    if ( menuflag ) {
      document.images[name].src = inImgs[name].src;

    }
  }
}