function imgMouseover(id)
{
  document.getElementById(id).src = "./../images/island/layout/" + id + "_hover.jpg";
}

function imgMouseout(id)
{
  document.getElementById(id).src = "./../images/island/layout/" + id + ".jpg";
}

function imgMousedown(id)
{
  document.getElementById(id).src = "./../images/island/layout/button_" + id + "_pressed.jpg";
}

function imgMouseup(id)
{
  document.getElementById(id).src = "./../images/island/layout/button_" + id + ".jpg";
}

function imgMouseoverHeader(link)
{
  document.getElementById("headerdiv").style.backgroundImage = "url(./../images/island/layout/header_" + link + ".jpg)";
}

function imgMouseoutHeader()
{
  document.getElementById("headerdiv").style.backgroundImage = "url(./../images/island/layout/header.jpg)";
}

function makeVisible(id)
{
  document.getElementById(id + "top").style.visibility = "visible";
  document.getElementById(id + "bottom").style.visibility = "visible";
}
function makeInvisible(id)
{
  document.getElementById(id + "top").style.visibility = "hidden";
  document.getElementById(id + "bottom").style.visibility = "hidden";
}