var windows = [ ];

var displays = [ ];

var offsets = [ ];

var directions = [ ];

var pause_count = [ ];




function register_wpe_scroller(windowId, displayId)
{
	windows.push(windowId);
	displays.push(displayId);
	offsets.push(0);
	directions.push(false);
	pause_count.push(0);
}

function wpe_scroll()
{
	for (var i = 0; i < windows.length; ++i)
	{
		pause = pause_count[i];
		if (pause)
		{
			--pause;
			pause_count[i] = pause;
		}
		else
		{
			windowId = windows[i];
			displayId = displays[i];
			offset = offsets[i];
			down = directions[i];
			startPause = false;

			d = document.getElementById(displayId);

			newTop = offset + "px";
			d.style.marginTop = newTop;

			if (down)
			{
				if (offset >= 0)
				{
					startPause = true;
				}
				else
				{
					++offset;
				}
			}
			else
			{
				if (offset < -15)
				{
					startPause = true;
				}
				else
				{
					--offset;
				}
			}

			if (startPause)
			{
				down = !down;
				pause_count[i] = 5;
			}

			offsets[i] = offset;
			directions[i] = down;
		}
	}
}


window.onload=function()
{
	wpe_scroller_init();
}

function wpe_scroller_init()
{
	setInterval('wpe_scroll()', 100);
}