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diff --git a/js/helper-classes/3D/element-planes.js b/js/helper-classes/3D/element-planes.js
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+++ b/js/helper-classes/3D/element-planes.js
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+/* <copyright>
+This file contains proprietary software owned by Motorola Mobility, Inc.<br/>
+No rights, expressed or implied, whatsoever to this software are provided by Motorola Mobility, Inc. hereunder.<br/>
+(c) Copyright 2011 Motorola Mobility, Inc.  All Rights Reserved.
+</copyright> */
+
+///////////////////////////////////////////////////////////////////////
+// Class ElementPlanes
+//      This class represents the 5 planes generated by an element
+//      in the world - the face itself, and one plane going back in Z
+//      for each side of the element.  Lines drawn will clip against
+//      those 5 planes.
+///////////////////////////////////////////////////////////////////////
+var viewUtils = require("js/helper-classes/3D/view-utils").ViewUtils,
+    vecUtils = require("js/helper-classes/3D/vec-utils").VecUtils,
+    Rectangle = require("js/helper-classes/3D/rectangle").Rectangle;
+
+var ElementPlanes = exports.ElementPlanes = Object.create(Object.prototype, {
+    ///////////////////////////////////////////////////////////////////////
+    // Instance variables
+    ///////////////////////////////////////////////////////////////////////
+
+    // maintain a back pointer to the original element
+    _elt: { value: null, writable: true },
+
+    // the 4 3D boundary points in world space
+    _boundaryPts: { value: null, writable: true },
+
+    // the 2D boundary rectangle.  Used for quick rejection tests.
+    _rect: { value: null, writable: true },
+    _zMin: { value: 0, writable: true },
+    _zMax: { value: 0, writable: true },
+
+    // keep a flag indicating that the element is back facing
+    _backFacing: { value: false, writable: true },
+
+    // cache the normal
+    _planeEq: { value: null, writable: true },
+
+    ///////////////////////////////////////////////////////////////////////
+    // Property accessors
+    ///////////////////////////////////////////////////////////////////////
+    setElement: { value: function( elt )       {  this._elt = elt;             } },
+    getElement: { value: function()            {  return this._elt;            } },
+
+    getPlaneEq: { value: function()            {  return this._planeEq.slice(0);  } },
+    setPlaneEq: { value: function(p)           {  this._planeEq = p;           } },
+
+    getRectangle: { value: function()            {  return this._rect;           } },
+    getBoundaryPoints: { value: function()            {  return this._boundaryPts;    } },
+    isBackFacing: { value: function()            {  return this._backFacing;     } },
+
+    getZMin: { value: function()            {  return this._zMin;           } },
+    getZMax: { value: function()            {  return this._zMax;           } },
+
+    ///////////////////////////////////////////////////////////////////////
+    // Methods
+    ///////////////////////////////////////////////////////////////////////
+    init: {
+        value: function()
+        {
+            if (this._elt)
+            {
+                // get the 3D boundary points
+                var elt = this._elt;
+                this._boundaryPts = viewUtils.getElementViewBounds3D( elt );
+                //var mat = viewUtils.getMatrixFromElement( elt );
+
+                var tmpMat = viewUtils.getLocalToGlobalMatrix( elt );
+                for (var i=0;  i<4;  i++)
+                {
+//                this._boundaryPts[i] = viewUtils.localToGlobal(this._boundaryPts[i], elt );
+                    this._boundaryPts[i] = viewUtils.localToGlobal2(this._boundaryPts[i], tmpMat);
+                }
+
+                // set the backfacing flag based on the direction of the normal
+                // for the purposes of stage drawing, we use a left-handed coordinate system
+                // (as opposed to the left-handed system used in the browser).  With that
+                // assumption, the points are specified counterclockwise on the stage, producing
+                // a negative Z for the normal, hence a positive Z implies back facing.
+                var nrm = this.computeNormal();
+                this._backFacing = false;
+                if (nrm[2] > 0)
+                    this._backFacing = true;
+                else
+                    MathUtils.negate( nrm );
+
+                // create the plane equation
+                //var d = -( nrm.dot( this._boundaryPts[0]) );
+                var d = -vecUtils.vecDot(3, nrm, this._boundaryPts[0]);
+                var planeEq = Vector.create( [nrm[0], nrm[1], nrm[2], d] );
+                this.setPlaneEq( planeEq );
+
+                // get the 2D rectangle
+                var rect = Object.create(Rectangle, {});
+                rect.setLeft( this._boundaryPts[0][0] );
+                rect.setTop( this._boundaryPts[0][1] );
+                rect.setRight( this._boundaryPts[0][0] );
+                rect.setBottom( this._boundaryPts[0][1] );
+                this._zMin = this._boundaryPts[0][2];
+                this._zMax = this._boundaryPts[0][2];
+                for (var i=1;  i<4;  i++)
+                {
+                    rect.unionPoint( this._boundaryPts[i] );
+                    var z = this._boundaryPts[i][2];
+                    if (z < this._zMin)  this._zMin = z;
+                    if (z > this._zMax)  this._zMax = z;
+                }
+                this._rect = rect;
+            }
+        }
+    },
+
+    computeNormal: {
+        value: function()
+        {
+            var xPts = new Array(),  yPts = new Array(),  zPts = new Array();
+            var n = this._boundaryPts.length;
+            for (var i=0;  i<n;  i++)
+            {
+                var pt = this._boundaryPts[i];
+                xPts.push( pt[0] );
+                yPts.push( pt[1] );
+                zPts.push( pt[2] );
+            }
+            var nrm = MathUtils.getPolygonNormal( n, xPts, yPts, zPts );
+
+            return nrm;
+        }
+    }
+
+});
+
+