// ++ CENTER POP-UP WINDOW ++ ***********
// **************************************
var version4 = (navigator.appVersion.charAt(0) == "4"); 
var popupHandle;
var position = 2;
//var url = "main.htm";
var name = "PopUp";
//var height = "680";
//var width = "925";
var evnt = "(version4 ? event : null)";
	
function display_popup(height, width, url){
// position=1 POPUP: makes screen display up and/or left, down and/or right 
// depending on where cursor falls and size of window to open
// position=2 CENTER: makes screen fall in center


	var properties = "toolbar = 0, location = 0, height = " + height;
	properties = properties + ", width=" + width;
	var leftprop, topprop, screenX, screenY, cursorX, cursorY, padAmt;
	if(navigator.appName == "Microsoft Internet Explorer"){
		screenY = document.body.offsetHeight;
		screenX = window.screen.availWidth;
	}else{
		screenY = window.outerHeight
		screenX = window.outerWidth
	}
	
	if(position == 1){ // if POPUP not CENTER
		cursorX = evnt.screenX;
		cursorY = evnt.screenY;
		padAmtX = 10;
		padAmtY = 10;
					
		if((cursorY + height + padAmtY) > screenY) {
			// make sizes a negative number to move left/up
			padAmtY = (-30) + (height * -1);
			// if up or to left, make 30 as padding amount
		}
	
		if((cursorX + width + padAmtX) > screenX)	{
			padAmtX = (-30) + (width * -1);	
			// if up or to left, make 30 as padding amount
		}
		
		if(navigator.appName == "Microsoft Internet Explorer") {
			leftprop = cursorX + padAmtX;
			topprop = cursorY + padAmtY;
		}else{
			leftprop = (cursorX - pageXOffset + padAmtX);
			topprop = (cursorY - pageYOffset + padAmtY);
	   }
	}else{
		leftvar = (screenX - width) / 2;
		rightvar = (screenY - height) / 2;
	if(navigator.appName == "Microsoft Internet Explorer") {
		leftprop = leftvar;
		topprop = rightvar;
	}else{
		leftprop = (leftvar - pageXOffset);
		topprop = (rightvar - pageYOffset);
   }
}
if(evnt != null){
	properties = properties + ", left = " + leftprop;
	properties = properties + ", top = " + topprop;
}
	popupHandle = open(url,name,properties);
}

// script prototype
//<a href="page.html"				
//	onClick="display_popup(533, 450, 'page.html'); return false;">
//</a>