//variable to hold reference to scroll layer
var lyr_scroll;

//variable holding scroll area width (set in initialization function)
var scroll_width;

//variable holding movement interval
var scroll_interval = 10;

//variable holding on status of scroller
var scroll_on;

//scrolling function
//controls movement carried out in move layer function
//val = 1 or -1 depending whether moving forward or backwards
function scrollLayer (val) {
	
	//check to make sure browser isn't ie5 and mac
	if (!(is_ie5up && is_mac)) {
	
		var movement = (val * scroll_interval);	//determine interval to move by
		var new_xpos = (movement + lyr_scroll.xpos);	//calculate value of new xpos
		
		//if movement falls within possible values
		//then scroll layer
		if ((new_xpos >= 0) && ((new_xpos + scroll_width) <= cart_width)) {
			moveLayer(movement);
			if (scroll_on) window.setTimeout('scrollLayer('+val+')',50);
		}
	
	}
	
}

function moveScreen(val) {

	if (is_ie5up && is_mac) {
		
		var movement = (275 * val);
		var new_xpos = (movement + lyr_scroll.xpos);	//calculate value of new xpos
		
		if ((new_xpos >= 0) && ((new_xpos + scroll_width) <= iemac_width)) moveLayer (movement);
	}

}

//move scrolling layer by absolute value
function moveLayer (val) {

	lyr_scroll.xpos += val;	//update left pos of scroll layer

	if (document.layers) {
		lyr_scroll.left = (-lyr_scroll.xpos + 3);
		lyr_scroll.clip.top = 0;
		lyr_scroll.clip.left = (lyr_scroll.xpos);
		lyr_scroll.clip.right = (lyr_scroll.xpos + scroll_width);
		lyr_scroll.clip.bottom = 90;
	}
	else if (document.all || document.getElementById) {
		lyr_scroll.style.left = ((-lyr_scroll.xpos) + 3);
		lyr_scroll.style.clip = 'rect(0px ' + (lyr_scroll.xpos + scroll_width) + 'px 90px ' + (lyr_scroll.xpos) + 'px)';
	}
	
}