/*
dw_util.js
utility functions (and 1 method for dynObj)
version date: August 2002
		
functions for getting window dimensions and scroll amount
from http://13thparallel.com/?issue=2002.06&title=viewport
				
This code is from Dynamic Web Coding 
www.dyn-web.com 
See Terms of Use at http://www.dyn-web.com/bus/terms.html
Permission granted to use this code 
as long as this entire notice is included.		
*/

// center in container (window or outer layer)
// NOTE: uses this.width/height properties of dynObj
// so make sure those have been obtained/set appropriately
// for type of content!!!!
dynObj.prototype.centerIn = function(outer) {
   var outWd, outHt, inWd, inHt, x, y;
   if (eval(outer)==window) {
      outWd=getWinWidth();
      outHt=getWinHeight();
   } else {
      outWd=outer.width;
      outHt=outer.height;
   }
   inWd=this.width;
   inHt=this.height;
   x=Math.round((outWd-inWd)/2);
   y=Math.round((outHt-inHt)/2);
   this.shiftTo(x,y);
}

// gets rendered height/width 
// for ns4, pass reference to layer. 
// for others, pass reference to layer or
// id of html element containing content (depends...)
function getWidth(obj,id) {
   var wd=0;
   if (document.getElementById||document.all) {
      var elem;
      if (id)	elem = (document.getElementById)? document.getElementById(id): document.all[id];
      else elem = obj;
      if (elem.offsetWidth) wd = elem.offsetWidth;
   } else if (obj.document) wd = obj.document.width;	// ns4
   return wd;
}

function getHeight(obj,id) {
   var ht=0;
   if (document.getElementById||document.all) {
      var elem;
      if (id)	elem = (document.getElementById)? document.getElementById(id): document.all[id];
      else elem = obj;
      if (elem.offsetHeight) ht = elem.offsetHeight;
   } else if (obj.document) ht = obj.document.height;	// ns4
   return ht;
}

// credit to http://www.13thparallel.com for the following 4 functions
// see http://13thparallel.com/?issue=2002.06&title=viewport
// returns width of window
function getWinWidth() {
   var winWd = 0;
   if (document.documentElement && document.documentElement.clientWidth) 
      winWd = document.documentElement.clientWidth;
   else if (document.body && document.body.clientWidth) 
      winWd = document.body.clientWidth;
   else if (document.body && document.body.offsetWidth) 
      winWd = document.body.offsetWidth; // ns6
   else if (window.innerWidth) winWd = window.innerWidth-18;
   return winWd;
}

// returns height of window
function getWinHeight() {
   var winHt = 0;
   if (window.innerHeight) winHt = window.innerHeight-18;
   else if (document.documentElement && document.documentElement.clientHeight) 
      winHt = document.documentElement.clientHeight;
   else if (document.body && document.body.clientHeight) 
      winHt = document.body.clientHeight;
   return winHt;
}	

// returns amount of vertical scroll
function getScrollY() {
   var scroll_y = 0;
   if (document.documentElement && document.documentElement.scrollTop)
      scroll_y = document.documentElement.scrollTop;
   else if (document.body && document.body.scrollTop) 
      scroll_y = document.body.scrollTop; 
   else if (window.pageYOffset)
      scroll_y = window.pageYOffset;
   else if (window.scrollY)
      scroll_y = window.scrollY;
   return scroll_y;
}

// returns amount of horizontal scroll
function getScrollX() {
   var scroll_x = 0;
   if (document.documentElement && document.documentElement.scrollLeft)
      scroll_x = document.documentElement.scrollLeft;
   else if (document.body && document.body.scrollLeft) 
      scroll_x = document.body.scrollLeft; 
   else if (window.pageXOffset)
      scroll_x = window.pageXOffset;
   else if (window.scrollX)
      scroll_x = window.scrollX;
   return scroll_x;
}