RWGltf_CafWriter does not export TDataStd_NamedData attributes to GLB

[sankalp0412]

Description
I attached TDataStd_NamedData attributes to shapes in an OCAF document, then exported the document to GLB using RWGltf_CafWriter. The attributes (e.g., "some_id") are present in the OCAF document but do not appear in the exported GLB.

I am new to OCCT, Is this behaviour expected?

Minimal Code:

      // 1. Create document
      Handle(TDocStd_Document) doc = new TDocStd_Document("OCCT-doc");

    // 2. Get shape tool
    Handle(XCAFDoc_ShapeTool) shape_tool = XCAFDoc_DocumentTool::ShapeTool(doc->Main());

    // 3. Create a sphere
    TopoDS_Shape shp = BRepPrimAPI_MakeSphere(40).Shape();

    // 4. Clean & mesh the shape
    BRepTools::Clean(shp);
    BRepMesh_IncrementalMesh mesh_algo(shp, true);
    mesh_algo.Perform();

    // 5. Add shape to document
    TDF_Label shape_label = shape_tool->AddShape(shp);

    // 6. Set a name
    TDataStd_Name::Set(shape_label, "sphere_0");

    // 7. Add NamedData
    Handle(TDataStd_NamedData) user_data = TDataStd_NamedData::Set(shape_label);
    user_data->SetString("some_id", "123");

    // 8. Prepare GLB writer
    RWGltf_WriterTrsfFormat format = RWGltf_WriterTrsfFormat_Compact;
    bool force_uv_export = true;
    bool binary = true;

    RWGltf_CafWriter writer("sphere.glb", binary);
    writer.SetTransformationFormat(format);
    writer.SetForcedUVExport(force_uv_export);

    TColStd_IndexedDataMapOfStringString file_info;
    file_info.Add(TCollection_AsciiString("Author"), TCollection_AsciiString("OCCT-Test"));

    Message_ProgressRange pr;

    // 9. Perform export
    writer.Perform(doc, file_info, pr);

[gkv311]

The metadata export in RWGltf_CafWriter requires OCCT 7.9.0 or newer - see news entry for glTF. I have tried your code snippet without modifications on OCCT 7.9.2 and it indeed produced "glb" file with extras section for a shape with { "some_id": "123" } data block.

[sankalp0412]

Thank you for the confirmation ! I think i was using an older version.
Regards,
Sankalp