var Slides = new Array();

var NEXT = -3;

var CurrALT = 0;
var CurrSRC = 0;
var CurrIMG = 0;
var CurrSlide = 0;

var NextIMG = 0;

var MESSAGE = '';

/*******************************************************************
 Set vars to point to the next slide.
*******************************************************************/
function BumpNext (Direction)
	{
	if (Direction > 0 )
		NEXT += 3
	else if ( Direction < 0 )
		NEXT -= 3;

	CurrALT = NEXT;
	CurrSRC = NEXT + 1;
	CurrIMG = NEXT + 2;
	CurrSlide = NEXT/3 + 1;
	}

/*******************************************************************
  The "disabled" property "grays out" the buttons if we're at the
  beginning or end of the list of slides. The routine attempts to keep
  one slide ahead by retrieving the CURR slide after displaying the
  current one.
*******************************************************************/
function ShowSlide(Direction)
	{
	BumpNext (Direction);

	frames["PICS"].document.images['Screen'].src = Slides[CurrIMG].src;
	frames["PICS"].document.images['Screen'].alt = Slides[CurrALT];

	frames["PICS"].document.SlideShow.Previous.disabled = (CurrIMG == 2);
	frames["PICS"].document.SlideShow.Next.disabled = (CurrIMG + 3 > Slides.length );

	MESSAGE = 'Picture ' + CurrSlide + ' of ' + Slides.length/3;
	self.defaultStatus = MESSAGE;

	return true;	
	}

/*******************************************************************
  Generally invoked from an onload function. This displays the first
  slide.
*******************************************************************/
function StartSlideShow()
	{
	BumpNext(0);
	ShowSlide(1);
	}