var selected = '';		// identifier of the currently selected image
var imgbase  = 'images/';	// base address image directory

// Image identifiers (= name attribute of the img objects)
var imgnames = new Array (
'box1',
'box2',
'box3',
'box4',
'box5',
'box6',
'box7',
'box8'
);

// Image files, displayed while NOT mouseover (and not selected)
var imgoff   = new Array (
imgbase+ 'leftbox_of.gif',
imgbase+ 'middlebox_of.gif', 
imgbase+ 'middlebox_of.gif', 
imgbase+ 'middlebox_of.gif', 
imgbase+ 'middlebox_of.gif', 
imgbase+ 'middlebox_of.gif', 
imgbase+ 'middlebox_of.gif', 
imgbase+ 'rightbox_of.gif'
);

// Image files, displayed while mouseover (and not selected)
var imgon    = new Array (
imgbase+ 'leftbox_on.gif',
imgbase+ 'middlebox_on.gif', 
imgbase+ 'middlebox_on.gif', 
imgbase+ 'middlebox_on.gif', 
imgbase+ 'middlebox_on.gif', 
imgbase+ 'middlebox_on.gif', 
imgbase+ 'middlebox_on.gif', 
imgbase+ 'rightbox_on.gif'
);

// Image files, displayed while the image has been clicked (is selected)
var imgsel   = new Array (7);

if ( document.images )
{
	window.status = 'Loading images...';

	// preload images
	for ( i=0; i<imgon.length; i++ )
	{	imagex = new Image();
		imagex.src = imgon[i];
	}
	for ( i=0; i<imgsel.length; i++ )
	{	if ( imgsel[i] != "" )
		{	imagex = new Image();
			imagex.src = imgsel[i];
		}
	}
	window.status = '';
}

// Function is called while mouseover or mouseout
// mouseover = 0 : mouseout  event
// mouseover = 1 : mouseover event
// imageID : index number of the image (0-based) or image identifier
function swapimage(mouseover, imageID)
{	if ( document.images )
	{	// Javascript 1.1 or higher!
		if ( typeof (imageID ) == 'string' )
		{	imageName = imageID;
			for ( i=0; i<imgnames.length; i++ )
			{	if ( imgnames[i] == imageName ) { imageNumber = i; break; }
			}
		} else
		{	imageName   = imgnames[imageID];
			imageNumber = imageID;
		}
		if ( document.images[imageName] )
		{	if ( ( imageName != selected )||( imgsel[imageNumber] == "" ) )
			{	// currently selected image will be skipped
				if ( mouseover == 1 )
				{ imageSrc = imgon[imageNumber];
				} else
				{ imageSrc = imgoff[imageNumber];
				}
				document.images[imageName].src = imageSrc;
			}
		}
	}
	return true;
}

// Function is called while the images is clicked
// imageID : index number of the image (0-based) or image identifier
function clicked (imageID)
{	if ( document.images )
	{	// Javascript 1.1 or higher!
		if ( typeof (imageID ) == 'string' )
		{ selected = imageID;
		} else
		{ selected = imgnames[imageID];
		}
		if ( document.images )
		{	for ( i=0; i<imgnames.length; i++ )
			{	if ( document.images[imgnames[i]] )
				{	if ( imgnames[i] == selected )
					{	if ( imgsel[i] != "" )
						{	document.images[imgnames[i]].src = imgsel[i];
						}
					} else
					{	document.images[imgnames[i]].src = imgoff[i];
					}
				}
			}
		}
	}
	return true;
}

// Image files, displayed while NOT mouseover (and not selected)
var navtxtimg = new Array (
imgbase+ 'section1text.gif',
imgbase+ 'section2text.gif', 
imgbase+ 'section3text.gif', 
imgbase+ 'section4text.gif', 
imgbase+ 'section5text.gif', 
imgbase+ 'section6text.gif', 
imgbase+ 'section7text.gif',
imgbase+ 'section8text.gif'
);

function chgnavtext (mouseover, number)
{	if ( document.images )
	{	if ( mouseover == 0 )
		{	document.images['navtext'].src = 'images/spacer.gif';
		} else
		{	document.images['navtext'].src = navtxtimg[number];
		}
	}
}