Photoshoppers inside - simple question awaits

<psd filename="layer_comps_mockup.psd" path="~/Desktop/" width="640" height="480">
   <layer name="Background" stack="0" position="0, 0" layerwidth="640" layerheight="480" transformpoint="center">Background.png</layer>
   <layer name="red_square" stack="1" position="0, 0" layerwidth="190" layerheight="190" transformpoint="center">red_square.png</layer>
   <layer name="yellow_circle" stack="2" position="31, 268" layerwidth="190" layerheight="190" transformpoint="center">yellow_circle.png</layer>
   <layer name="white_star" stack="3" position="221, 94" layerwidth="218" layerheight="207" transformpoint="center">white_star.png</layer>
   <layer name="green_pentagon" stack="4" position="426, 29" layerwidth="192" layerheight="192" transformpoint="center">green_pentagon.png</layer>
   <layer name="blue_triangle" stack="5" position="255, 301" layerwidth="168" layerheight="155" transformpoint="center">blue_triangle.png</layer>
   <layer name="black_rectangle" stack="6" position="493, 242" layerwidth="106" layerheight="216" transformpoint="center">black_rectangle.png</layer>
</psd> 

//
// This script exports extended layer.bounds information to [psd_file_name].xml
// by pattesdours
//

function docCheck() {
    // ensure that there is at least one document open
    if (!documents.length) {
        alert('There are no documents open.');
        return; // quit
    }
}

docCheck();

var originalRulerUnits = preferences.rulerUnits;
preferences.rulerUnits = Units.PIXELS;

var docRef = activeDocument;

var docWidth = docRef.width.value;
var docHeight = docRef.height.value;
var mySourceFilePath = activeDocument.fullName.path + "/";

//  Code to get layer index / descriptor
//
cTID = function(s) { return app.charIDToTypeID(s); };
sTID = function(s) { return app.stringIDToTypeID(s); };
function getLayerDescriptor (doc, layer) {
    var ref = new ActionReference();
    ref.putEnumerated(cTID("Lyr "), cTID("Ordn"), cTID("Trgt"));
    return executeActionGet(ref)
};

function getLayerID(doc, layer) {
  var d = getLayerDescriptor(doc, layer);
  return d.getInteger(cTID('LyrI'));
};

var stackorder = 0;

// function from Xbytor to traverse all layers
traverseLayers = function(doc, ftn, reverse) {
  function _traverse(doc, layers, ftn, reverse) {
    var ok = true;
    for (var i = 1; i <= layers.length && ok != false; i++) {
      var index = (reverse == true) ? layers.length-i : i - 1;
      var layer = layers[index];

      if (layer.typename == "LayerSet") {
        ok = _traverse(doc, layer.layers, ftn, reverse);

      } else {
  stackorder = stackorder + 1;
        ok = ftn(doc, layer, stackorder);
      }
    }
    return ok;
  };

  return _traverse(doc, doc.layers, ftn, reverse);
};

// create a string to hold the data
var str ="";

// class using a contructor
function cLayer(doc, layer) {

//this.layerID = Stdlib.getLayerID(doc, layer);
    this.layerID = getLayerID(doc, layer);
  //alert("layer ID: " + this.layerID);
    this.layerWidth = layer.bounds[2].value - layer.bounds[0].value;
      this.layerHeight = layer.bounds[3].value - layer.bounds[1].value;
  
    // these return object coordinates relative to canvas
      this.upperLeftX = layer.bounds[0].value;
      this.upperLeftY = layer.bounds[1].value;
      this.upperCenterX = this.layerWidth / 2 + layer.bounds[0].value;
      this.upperCenterY = layer.bounds[1].value;
      this.upperRightX = layer.bounds[2].value;
      this.upperRightY = layer.bounds[1].value;
      this.middleLeftX = layer.bounds[0].value;
      this.middleLeftY = this.layerHeight / 2 + layer.bounds[1].value;
      this.middleCenterX = this.layerWidth / 2 + layer.bounds[0].value;
      this.middleCenterY = this.layerHeight / 2 + layer.bounds[1].value;
      this.middleRightX = layer.bounds[2].value;
      this.middleRightY = this.layerHeight / 2 + layer.bounds[1].value;
      this.lowerLeftX = layer.bounds[0].value;
      this.lowerLeftY = layer.bounds[3].value;
      this.lowerCenterX = this.layerWidth / 2 + layer.bounds[0].value;
      this.lowerCenterY = layer.bounds[3].value;
      this.lowerRightX = layer.bounds[2].value;
      this.lowerRightY = layer.bounds[3].value;
      
      // I'm adding these for easier editing of flash symbol transformation point (outputs a 'x, y' format)
      // because I like to assign shortcut keys that use the numeric pad keyboard, like such:
      //        7    8    9
      //        4    5    6
      //        1    2    3
      //
      this.leftBottom = this.lowerLeftX + ", " + this.lowerLeftY;
      this.bottomCenter = this.lowerCenterX + ", " + this.lowerCenterY;
      this.rightBottom = this.lowerRightX + ", " + this.lowerRightY;
      
      this.leftCenter = this.middleLeftX + ", " + this.middleLeftY;
      this.center = this.middleCenterX + ", " + this.middleCenterY;
      this.rightCenter = this.middleRightX + ", " + this.middleRightY;
      
      this.leftTop = this.upperLeftX + ", " + this.upperLeftY;
      this.topCenter = this.upperCenterX + ", " + this.upperCenterY;
      this.rightTop = this.upperRightX + ", " + this.upperRightY;

    // these return object coordinates relative to layer bounds
      this.relUpperLeftX = layer.bounds[1].value - layer.bounds[1].value;
      this.relUpperLeftY =  layer.bounds[0].value - layer.bounds[0].value;
      this.relUpperCenterX = this.layerWidth / 2;
      this.relUpperCenterY = layer.bounds[0].value - layer.bounds[0].value;
      this.relUpperRightX = this.layerWidth;
      this.relUpperRightY = layer.bounds[0].value - layer.bounds[0].value;
      this.relMiddleLeftX = layer.bounds[1].value - layer.bounds[1].value;
      this.relMiddleLeftY = this.layerHeight / 2;
      this.relMiddleCenterX = this.layerWidth / 2;
      this.relMiddleCenterY = this.layerHeight / 2;
      this.relMiddleRightX = this.layerWidth;
    this.relMiddleRightY = this.layerHeight / 2;
      this.relLowerLeftX = layer.bounds[1].value - layer.bounds[1].value;
      this.relLowerLeftY = this.layerHeight;
      this.relLowerCenterX = this.layerWidth / 2;
    this.relLowerCenterY = this.layerHeight / 2;
      this.relLowerRightY = this.layerHeight;
      this.relLowerRightX = this.layerWidth;
      this.relLowerRightY = this.layerHeight;
  
  return this;
}

// add header line
str = "<psd filename=\"" + docRef.name + "\" path=\"" + mySourceFilePath + "\" width=\"" + docWidth + "\" height=\"" + docHeight + "\">\n";

// now a function to collect the data
function exportBounds(doc, layer, i) {
    var isVisible = layer.visible;
    var layerData = cLayer(doc, layer);

  if(isVisible){
// Layer object main coordinates relative to its active pixels
    var str2 = "\t<layer name=\"" + layer.name 
    + "\" stack=\"" + (i - 1) // order in which layers are stacked, starting with zero for the bottom-most layer
    + "\" position=\"" + leftTop // this is the 
    + "\" layerwidth=\"" + layerData.layerWidth 
    + "\" layerheight=\"" + layerData.layerHeight 
    + "\" transformpoint=\"" + "center" + "\">" // hard-coding 'center' as the default transformation point
    + layer.name + ".png" + "</layer>\n" // I have to put some content here otherwise sometimes tags are ignored
str += str2.toString();
   };
};


// call X's function using the one above
traverseLayers(app.activeDocument, exportBounds, true);

// Use this to export XML file to same directory where PSD file is located
    var mySourceFilePath = activeDocument.fullName.path + "/";
// create a reference to a file for output
    var csvFile = new File(mySourceFilePath.toString().match(/([^\.]+)/)[1] + app.activeDocument.name.match(/([^\.]+)/)[1] + ".xml");
// open the file, write the data, then close the file
csvFile.open('w');
csvFile.writeln(str + "</psd>");
csvFile.close();
preferences.rulerUnits = originalRulerUnits;
// Confirm that operation has completed
alert("Operation Complete!" + "\n" + "Layer coordinates were successfully exported to:" + "\n" + "\n" + mySourceFilePath.toString().match(/([^\.]+)/)[1] + app.activeDocument.name.match(/([^\.]+)/)[1] + ".xml");