function newImage(arg) {
	if (document.images) {
		rslt = new Image();
		rslt.src = arg;
		return rslt;
	}
}

function changeImages() {
	if (document.images && (preloadFlag == true)) {
		for (var i=0; i<changeImages.arguments.length; i+=2) {
			document[changeImages.arguments[i]].src = changeImages.arguments[i+1];
		}
	}
}

var preloadFlag = false;
function preloadImages() {
	if (document.images) {
		bt_home_over = newImage("images/bt_home-over.gif");
		bt_story_over = newImage("images/bt_story-over.gif");
		bt_thecrew_over = newImage("images/bt_thecrew-over.gif");
		bt_map_over = newImage("images/bt_map-over.gif");
		bt_listen_over = newImage("images/bt_listen-over.gif");
		preloadFlag = true;
	}
}

//********************************************************
// Pop Up window script
//********************************************************
// openPopWin(winURL, winWidth, winHeight [, winFeatures, [winLeft, winTop]]) 
// winURL - url of document to be loaded into window or "". 
// winWidth - width of image in pixels. 
// winHeight - height of image in pixels. 
// winFeatures - a comma separated list of additional features, see below. 
// winLeft - see "Controlling the Location of Pop-up's" for more information. 
// winTop - see "Controlling the Location of Pop-up's" for more information. 
// winURL, winWidth, and winHeight are required. winFeatures, winLeft, and winTop are optional. 

// here's an example:
// <A HREF="JavaScript:openPopWin('/inside/pledge/raffle_rr.asp', 416, 500, 'scrollbars,resizable', 100, 50);">

var popWin = null    // use this when referring to pop-up window
var winCount = 0
var winName = "popWin"

function openPopWin(winURL, winWidth, winHeight, winFeatures, winLeft, winTop){
  var d_winLeft = 20  // default, pixels from screen left to window left
  var d_winTop = 20   // default, pixels from screen top to window top
  winName = "popWin" + winCount++ //unique name for each pop-up window
  closePopWin()           // close any previously opened pop-up window
  if (openPopWin.arguments.length >= 4)  // any additional features? 
    winFeatures = "," + winFeatures
  else 
    winFeatures = "" 
  if (openPopWin.arguments.length == 6)  // location specified
    winFeatures += getLocation(winWidth, winHeight, winLeft, winTop)
  else
    winFeatures += getLocation(winWidth, winHeight, d_winLeft, d_winTop)
  popWin = window.open(winURL, winName, "width=" + winWidth 
           + ",height=" + winHeight + winFeatures)
  }
  
function closePopWin(){    // close pop-up window if it is open 
  if (navigator.appName != "Microsoft Internet Explorer" 
      || parseInt(navigator.appVersion) >=4) //do not close if early IE
    if(popWin != null) if(!popWin.closed) popWin.close() 
  }
  
function getLocation(winWidth, winHeight, winLeft, winTop){
  return ""
  }

function getLocation(winWidth, winHeight, winLeft, winTop){
  var winLocation = ""
  if (winLeft < 0)
    winLeft = screen.width - winWidth + winLeft
  if (winTop < 0)
    winTop = screen.height - winHeight + winTop
  if (winTop == "cen")
    winTop = (screen.height - winHeight)/2 - 20
  if (winLeft == "cen")
    winLeft = (screen.width - winWidth)/2
  if (winLeft>0 & winTop>0)
    winLocation =  ",screenX=" + winLeft + ",left=" + winLeft	
                + ",screenY=" + winTop + ",top=" + winTop
  else
    winLocation = ""
  return winLocation
  }