home_on = new Image( 90, 40 );
home_on.src = "img/home_on.png";
home_off = new Image( 90, 40 );
home_off.src = "img/home_off.png";

function _msie_replace_png_imgs() {
	var i, elements;

	elements = document.getElementsByTagName( "img" );
	for ( i = 0; i < elements.length; i++ ) {
		var img = elements[i];
		if ( img.src.toLowerCase().search(/\.png$/ ) < 0 ) continue;

		img.style.filter = "progid:DXImageTransform.Microsoft.AlphaImageLoader(src='" + img.src	+ "', sizingMethod='image')";
		img.src = "img/spacer.gif";
	}
}

if ( window.attachEvent && navigator.appName == "Microsoft Internet Explorer" ) window.attachEvent ( "onload", _msie_replace_png_imgs );

if ( navigator.appName == "Netscape" ) {
	window.addEventListener ( "resize", _popCenter, false );
	window.addEventListener ( "scroll", _popCenter, false );
} else if ( navigator.appName == "Opera" || navigator.appVersion.indexOf( "Macintosh" ) < 0 ) {
	window.attachEvent ( "onresize", _popCenter );
	window.attachEvent ( "onscroll", _popCenter );
}

var offset, windowWidth, windowHeight, windowOffset, imageNumber, photoFrameHeight = 0, currentSetNumber, currentImageNumber;

function _popMove( photoFrameHeight ) {
	if ( navigator.appName == "Netscape" || navigator.appName == "Opera" ) {
		windowWidth  = window.innerWidth;
		windowHeight = window.innerHeight;
		windowOffset = window.pageYOffset;
	} else if ( document.documentElement.clientWidth ) {
		windowWidth  = document.documentElement.clientWidth;
		windowHeight = document.documentElement.clientHeight;
		windowOffset = document.documentElement.scrollTop;
	} else {
		windowWidth  = document.body.clientWidth;
		windowHeight = document.body.clientHeight;
		windowOffset = document.body.scrollTop;
	}
	offset = Math.floor (( windowWidth - photoFrame.offsetWidth ) / 2 );
	offset < 0 ? offset = 10 : offset;
	photoFrame.style.left = offset + 'px';
	offset = Math.floor (( windowHeight - photoFrameHeight ) / 2 );
	offset < 0 ? offset = 10 : offset;
	photoFrame.style.top = eval( windowOffset + offset ) + 'px';
	overlay.style.top = windowOffset + "px";
}

function _popUp ( setNumber, imageNumber ) {
	currentSetNumber = setNumber;
	currentImageNumber = imageNumber;
	camera = eval ( "camera_" + setNumber + "_off" );
	camera.src = "img/camera_done.gif";
	photoImage.src = "img/" + setNumber + "_" + imageNumber + ".jpg";
	textHeight.innerHTML = photoText[setNumber][imageNumber];
	photoFrameHeight = 400 + textHeight.clientHeight;
	_popMove ( photoFrameHeight );
	if ( overlaySwitch ) overlay.style.visibility = "visible";
	photoFrame.style.visibility = "visible";
}

function _popDown () {
	photoImage.src = "img/spacer.gif"
	photoFrame.style.visibility = "hidden";
	overlay.style.visibility = "hidden";
	imageNumber = 0;
}

function _popCenter () {
	_popMove ( photoFrameHeight );
}

function _popNext () {
	currentImageNumber + 1 < photoCounts[currentSetNumber] ? _popUp ( currentSetNumber, currentImageNumber + 1 )  :  _popUp ( currentSetNumber, 0 ) ;
}

function _popBack () {
	currentImageNumber - 1 >= 0 ? _popUp ( currentSetNumber, currentImageNumber - 1 )  :  _popUp ( currentSetNumber, photoCounts[currentSetNumber] - 1 ) ;
}