/// <summary>
        /// This version uses the new Geometry representation
        /// </summary>
        /// <param name="model"></param>
        /// <param name="context"></param>
        /// <param name="exclude">List of type to exclude, by default excplict openings and spaces are excluded if exclude = null</param>
        /// <returns></returns>
        private void BuildScene(Xbim3DModelContext context)
        {
           
            //get a list of all the unique styles
            Dictionary<int, WpfMaterial> styles = new Dictionary<int, WpfMaterial>();
            Dictionary<int, MeshGeometry3D> shapeGeometries = new Dictionary<int, MeshGeometry3D>();
            Dictionary<int, WpfMeshGeometry3D> meshSets = new Dictionary<int, WpfMeshGeometry3D>();
            Model3DGroup opaques = new Model3DGroup();
            Model3DGroup transparents = new Model3DGroup();

            foreach (var shapeGeom in context.ShapeGeometries())
            {
                MeshGeometry3D wpfMesh = new MeshGeometry3D();
                wpfMesh.SetValue(TagProperty, shapeGeom); //don't read the geometry into the mesh yet as we do not know where the instance is located
                shapeGeometries.Add(shapeGeom.ShapeLabel, wpfMesh);
            }


            foreach (var style in context.SurfaceStyles())
            {
                WpfMaterial wpfMaterial = new WpfMaterial();
                wpfMaterial.CreateMaterial(style);
                styles.Add(style.DefinedObjectId, wpfMaterial);
                WpfMeshGeometry3D mg = new WpfMeshGeometry3D(wpfMaterial, wpfMaterial);
                meshSets.Add(style.DefinedObjectId, mg);
                if (style.IsTransparent)
                    transparents.Children.Add(mg);
                else
                    opaques.Children.Add(mg);

            }

            ////if (!styles.Any()) return ; //this should always have something unless the model is empty
            ////double metre = model.ModelFactors.OneMetre;
            ////XbimMatrix3D wcsTransform = XbimMatrix3D.CreateTranslation(_modelTranslation) * XbimMatrix3D.CreateScale((float)(1 / metre));

            ////foreach (var shapeInstance in context.ShapeInstances()
            ////        .Where(s => s.RepresentationType == XbimGeometryRepresentationType.OpeningsAndAdditionsIncluded &&
            ////            !typeof(IfcFeatureElement).IsAssignableFrom(IfcMetaData.GetType(s.IfcTypeId)) &&
            ////            !typeof(IfcSpace).IsAssignableFrom(IfcMetaData.GetType(s.IfcTypeId))))
            ////{
            ////    int styleId = shapeInstance.StyleLabel > 0 ? shapeInstance.StyleLabel : shapeInstance.IfcTypeId * -1;

            ////    //GET THE ACTUAL GEOMETRY 
            ////    MeshGeometry3D wpfMesh;
            ////    //see if we have already read it
            ////    if (shapeGeometries.TryGetValue(shapeInstance.ShapeGeometryLabel, out wpfMesh))
            ////    {
            ////        GeometryModel3D mg = new GeometryModel3D(wpfMesh, styles[styleId]);
            ////        mg.SetValue(TagProperty, new XbimInstanceHandle(model, shapeInstance.IfcProductLabel, shapeInstance.IfcTypeId));
            ////        mg.BackMaterial = mg.Material;
            ////        mg.Transform = XbimMatrix3D.Multiply(shapeInstance.Transformation, wcsTransform).ToMatrixTransform3D();
            ////        if (styles[styleId].IsTransparent)
            ////            transparents.Children.Add(mg);
            ////        else
            ////            opaques.Children.Add(mg);
            ////    }
            ////    else //we need to get the shape geometry
            ////    {
            ////        XbimShapeGeometry shapeGeom = context.ShapeGeometry(shapeInstance.ShapeGeometryLabel);
            ////        if (shapeGeom.ReferenceCount > 1) //only store if we are going to use again
            ////        {
            ////            wpfMesh = new MeshGeometry3D();
            ////            wpfMesh.Read(shapeGeom.ShapeData);
            ////            shapeGeometries.Add(shapeInstance.ShapeGeometryLabel, wpfMesh);
            ////            GeometryModel3D mg = new GeometryModel3D(wpfMesh, styles[styleId]);
            ////            mg.SetValue(TagProperty, new XbimInstanceHandle(model, shapeInstance.IfcProductLabel, shapeInstance.IfcTypeId));
            ////            mg.BackMaterial = mg.Material;
            ////            mg.Transform = XbimMatrix3D.Multiply(shapeInstance.Transformation, wcsTransform).ToMatrixTransform3D();
            ////            if (styles[styleId].IsTransparent)
            ////                transparents.Children.Add(mg);
            ////            else
            ////                opaques.Children.Add(mg);
            ////        }
            ////        else //it is a one off, merge it with shapes of a similar material
            ////        {
            ////            WpfMeshGeometry3D mg = meshSets[styleId];
            ////            mg.Add(shapeGeom.ShapeData,
            ////                shapeInstance.IfcTypeId,
            ////                shapeInstance.IfcProductLabel,
            ////                shapeInstance.InstanceLabel,
            ////                XbimMatrix3D.Multiply(shapeInstance.Transformation, wcsTransform), 0);
            ////        }
            ////    }

            ////}

            if (opaques.Children.Any())
            {
                ModelVisual3D mv = new ModelVisual3D();
                mv.Content = opaques;
                Opaques.Children.Add(mv);
                if (_modelBounds.IsEmpty) _modelBounds = mv.Content.Bounds.ToXbimRect3D();
                else _modelBounds.Union(mv.Content.Bounds.ToXbimRect3D());
            }
            if (transparents.Children.Any())
            {
                ModelVisual3D mv = new ModelVisual3D();
                mv.Content = transparents;
                Transparents.Children.Add(mv);
                if (_modelBounds.IsEmpty) _modelBounds = mv.Content.Bounds.ToXbimRect3D();
                else _modelBounds.Union(mv.Content.Bounds.ToXbimRect3D());
            }

        }