/*
 *
 * ==========================================================
 * Function:     srcollrun
 * Syntax:       srcollrun(speech, div, td1, td2)
 * Introduce:    Scroll Word!!!
 *               scrollup:    down -> up
 *               scrolldown:  up -> down
 * First Author: Zhencheng Yang
 * Time:         2010.10.19 15:38
 * Test:         IE7, IE8, Firefox 3.6
 * ==========================================================
 *
 */
function srcollrun(speech, d1, d2, d3)
{
	var su = new Object();
	
	su.div1 = document.getElementById(d1);
	su.tb1 = document.getElementById(d2);
	su.tb2 = document.getElementById(d3);
	
	su.marqup = function()
	{
		if( su.tb2.offsetHeight - su.div1.scrollTop < 0 )
		{
			su.div1.scrollTop -= su.tb1.offsetHeight;
		}
		else
		{
			su.div1.scrollTop++;
		}
	}
	
	su.srcollup = function()
	{
		var runpoint = setInterval(su.marqup, speech);
		su.tb2.innerHTML = su.tb1.innerHTML;
	
		su.div1.onmouseover = function()
		{
			clearInterval(runpoint);
		}
	
		su.div1.onmouseout = function()
		{
			runpoint = setInterval(su.marqup, speech);
		}
	}
	
	su.marqdown = function()
	{
		if( su.tb1.offsetTop - su.div1.scrollTop >= 0 )
		{
			su.div1.scrollTop += su.tb2.offsetHeight;
		}
		else
		{
			su.div1.scrollTop--;
		}
	}
	
	su.srcolldown = function()
	{
		su.tb2.innerHTML = su.tb1.innerHTML;
		su.div1.scrollTop = su.div1.scrollHeight;
		
		var runpoint = setInterval(su.marqdown, speech);
	
		su.div1.onmouseover = function()
		{
			clearInterval(runpoint);
		}
	
		su.div1.onmouseout = function()
		{
			runpoint = setInterval(su.marqdown, speech);
		}
	}
	
	return su;
}