// IE
isIE = (document.all ? true : false);
// IE5, NS6 
isDOM = (document.getElementById ? true : false);

function getAbsX(elt) { return (elt.x) ? elt.x : getAbsPos(elt,"Left"); }
function getAbsY(elt) { return (elt.y) ? elt.y : getAbsPos(elt,"Top"); }
function getAbsPos(elt,which) {
 iPos = 0;
 while (elt != null) {
  iPos += elt["offset" + which];
  elt = elt.offsetParent;
 }
 return iPos;
}

function getDivStyle(divname) {
 var style;
 if (isDOM) { style = document.getElementById(divname).style; }
 else { style = isIE ? document.all[divname].style
                     : document.layers[divname]; } // NS4
 return style;
}

function hideElement(divname) {
 getDivStyle(divname).visibility = 'hidden';
}

function moveBy(elt,deltaX,deltaY) {
 elt.left = parseInt(elt.left) + deltaX;
 elt.top = parseInt(elt.top) + deltaY;
}

function toggleVisible(divname) {
 divstyle = getDivStyle(divname);
 if (divstyle.visibility == 'visible' || divstyle.visibility == 'show') {
   divstyle.visibility = 'hidden';
 } else {
   //fixPosition(divname);
   divstyle.visibility = 'visible';
 }
}

function setPosition(elt,positionername,isPlacedUnder) {
 var positioner;
 if (isIE) {
  positioner = document.all[positionername];
 } else {
  if (isDOM) {
    positioner = document.getElementById(positionername);
  } else {
    positioner = document.layers[positionername];
  }
 }
 elt.left = getAbsX(positioner);
 elt.top = getAbsY(positioner) + (isPlacedUnder ? positioner.height : 0);
}

// fixPosition() attaches the element named eltname
// to an image named eltname+'Pos'
//
function fixPosition(divname) {
 divstyle = getDivStyle(divname);
 positionerImgName = divname + 'Pos';
 // hint: try setting isPlacedUnder to false
 isPlacedUnder = true;
 if (isPlacedUnder) {
  setPosition(divstyle,positionerImgName,true);
 } else {
  setPosition(divstyle,positionerImgName)
 }
}