////////////////////////////////////////////////////////////////////////////////
// (c) 2001, SCS Telemedia [http://www.telemedia.ch/], Simon Wunderlin
//
// constructor /////////////////////////////////////////////////////////////////
var defaultImage;
function rolloverButton( imgFName, /* optional */ imgName ) {
	this.fnm = imgFName;                        // this image's name
	this.nm = ( imgName ) ? imgName : imgFName; // this image's filepart
		
	// create Object
	this.off = new Image(); this.on  = new Image();
	this.off.src = imagesDir + this.fnm + imagesOff + imagesExt;
	this.on.src  = imagesDir + this.fnm + imagesOn + imagesExt;
	this.statusOn  = ''; this.statusOff = '';   // status messages
}

// utility functions ///////////////////////////////////////////////////////////
function img_clearAll() {
	for ( i=0; i<aImages.length; i++ )
		if ( aImages[i] )
			if ( document.images[aImages[i].nm] )
				document.images[aImages[i].nm].src = aImages[i].off.src;
}

// eventhandling functions /////////////////////////////////////////////////////
function img_act( imgName, setDefault ) {
	img_clearAll();                   // clear all images

	for (i=0; i<aImages.length; i++)  // find img Object
		if ( aImages[i] )
			if ( aImages[i].nm == imgName ) thisImg = aImages[i];

	if (setDefault) defaultImage = thisImg;
	
	if ( thisImg ) {                  // highlight appropriate image
		document.images[thisImg.nm].src = thisImg.on.src;
		window.status = thisImg.statusOn; return true;
	}
}

function img_inact( imgName ) {
	if ( defaultImage ) {
		img_clearAll(); // clear all
		document.images[defaultImage.nm].src = defaultImage.on.src;
		window.status = thisImg.statusOff;
	} return true;
}