Navisworks COM API for Exporting geometry and calculating faces and vertices - autodesk

Question

I am trying to export the vertices, faces and colors of a selected object in the Navis. After a bit of research I found that we can do it using the COM API provided by the Navisworks. I used getprimitives to find the triangles. which looks is something as below.
'using Autodesk.Navisworks.Api;
using Autodesk.Navisworks.Api.Plugins;
using ComBridge = Autodesk.Navisworks.Api.ComApi.ComApiBridge;
using COMApi = Autodesk.Navisworks.Api.Interop.ComApi;
#region InwSimplePrimitivesCB Class
class CallbackGeomListener : COMApi.InwSimplePrimitivesCB
{
public void Line(COMApi.InwSimpleVertex v1,
COMApi.InwSimpleVertex v2)
{
// do your work
}
public void Point(COMApi.InwSimpleVertex v1)
{
// do your work
}
public void SnapPoint(COMApi.InwSimpleVertex v1)
{
// do your work
}
public void Triangle(COMApi.InwSimpleVertex v1,
COMApi.InwSimpleVertex v2,
COMApi.InwSimpleVertex v3)
{
// do your work
}
}
#endregion
#region NW Plugin
[PluginAttribute("Test","ADSK",DisplayName= "Test")]
[AddInPluginAttribute(AddInLocation.AddIn)]
public class Class1:AddInPlugin
{
public override int Execute(params string[] parameters)
{
// get the current selection
ModelItemCollection oModelColl =
Autodesk.Navisworks.Api.Application.
ActiveDocument.CurrentSelection.SelectedItems;
//convert to COM selection
COMApi.InwOpState oState = ComBridge.State;
COMApi.InwOpSelection oSel =
ComBridge.ToInwOpSelection(oModelColl);
// create the callback object
CallbackGeomListener callbkListener =
new CallbackGeomListener();
foreach (COMApi.InwOaPath3 path in oSel.Paths())
{
foreach (COMApi.InwOaFragment3 frag in path.Fragments())
{
// generate the primitives
frag.GenerateSimplePrimitives(
COMApi.nwEVertexProperty.eNORMAL,
callbkListener);
}
}
return 0;
}
}
#endregion
'
The problem here is I am not able to find faces, I do get vertices by using triangle method.
Please let me know if anyone knows how to find faces and color of the object.