//###########################################################################
//# js.top_floater.js
//###########################################################################
//# top button
//###########################################################################
var lastScrollY = 0;
var diffY = 0;
function heartBeat()
{
	if(document.all)	diffY = document.body.scrollTop;
	else				diffY = window.pageYOffset;

	if(diffY != lastScrollY)
	{
		var percent = 0.1 * (diffY - lastScrollY);

		if (percent > 0)	percent = Math.ceil(percent);
		else				percent = Math.floor(percent);

		if(document.all)	document.all.floater.style.pixelTop += percent;
		else
		{
			var tmp = window.document.getElementById('floater').style.top;
			var top_value = parseInt(tmp.substr(0, tmp.length -2));
			top_value = top_value + percent;
			window.document.getElementById('floater').style.top = top_value;
		}
		lastScrollY = lastScrollY + percent;
	}
}