function preLoad() {
   menuImgs = new Array();
   menuImgs[0] = new Object();
   menuImgs[0].location = document.home;
   menuImgs[0].images = new Array();
   menuImgs[0].images[0] = new Image();
   menuImgs[0].images[0].src = "images/home1.png";
   menuImgs[0].images[1] = new Image();
   menuImgs[0].images[1].src = "images/home2.png";
   menuImgs[0].images[2] = new Image();
   menuImgs[0].images[2].src = "images/home3.png";

   menuImgs[1] = new Object();
   menuImgs[1].location = document.inv;
   menuImgs[1].images = new Array();
   menuImgs[1].images[0] = new Image();
   menuImgs[1].images[0].src = "images/inv1.png";
   menuImgs[1].images[1] = new Image();
   menuImgs[1].images[1].src = "images/inv2.png";
   menuImgs[1].images[2] = new Image();
   menuImgs[1].images[2].src = "images/inv3.png";

   menuImgs[2] = new Object();
   menuImgs[2].location = document.gall;
   menuImgs[2].images = new Array();
   menuImgs[2].images[0] = new Image();
   menuImgs[2].images[0].src = "images/gall1.png";
   menuImgs[2].images[1] = new Image();
   menuImgs[2].images[1].src = "images/gall2.png";
   menuImgs[2].images[2] = new Image();
   menuImgs[2].images[2].src = "images/gall3.png";

   menuImgs[3] = new Object();
   menuImgs[3].location = document.cont;
   menuImgs[3].images = new Array();
   menuImgs[3].images[0] = new Image();
   menuImgs[3].images[0].src = "images/cont1.png";
   menuImgs[3].images[1] = new Image();
   menuImgs[3].images[1].src = "images/cont2.png";
   menuImgs[3].images[2] = new Image();
   menuImgs[3].images[2].src = "images/cont3.png";
}

function swapImgs(l,i) {
   menuImgs[l].location.src = menuImgs[l].images[i].src;
}