/************************************************************/
/*   image_rollover.js  -  image preload/rollover functions  */
/*   Last Update:  02/07/2002                                */
/*   Branton K. Davis                                        */
/*   Web Developer / Programmer / Resident Tech Dork         */
/*   Washburn University                                     */
/*   Division of Continuing Education                        */
/*   E-Mail:  branton.davis@washburn.edu                     */
/*   Web:  www.washburn.edu/ce                               */
/************************************************************/

function preloadImages()
{
	if ( document.images )
	{
		var rollImages = new Array();
		var args = preloadImages.arguments;
		rolloverExtension = args[0];

		for ( var imageNumber = 1 ; imageNumber < args.length ; imageNumber++ )
		{
			rollImages[imageNumber] = new Image();
			rollImages[imageNumber].src = args[imageNumber];
		}
	}
}

function swapImage(imageNumber)
{
	if ( document.images )
	{
		if (document.images[imageNumber])
		{
			var stringLength = document.images[imageNumber].src.length;
			var imageType = document.images[imageNumber].src.substring((stringLength - 4),stringLength);

			if ( (x = document.images[imageNumber].src.indexOf(rolloverExtension)) != -1 )
			{
				document.images[imageNumber].src = document.images[imageNumber].src.substring(0,x) + imageType;
			}
			else
			{
				document.images[imageNumber].src = document.images[imageNumber].src.substring(0,(stringLength - 4)) + rolloverExtension + imageType;
			}
		}
	}
}