In VtkGLTF_importer I am getting the hierarchy. However while exporting glb file using gltf_exporter it getting lost. Please help me in this.

Support
1

In glb file multiple texture and hierarchy is not coming.

2

please share some code and data

3 
import vtk

INPUT_FILE = "input_glb.glb"
OUTPUT_FILE = "output_glb.glb"

renderer = vtk.vtkRenderer()
renderWindow = vtk.vtkRenderWindow()
renderWindow.AddRenderer(renderer)

importer = vtk.vtkGLTFImporter()
importer.SetFileName(INPUT_FILE) 
importer.SetRenderWindow(renderWindow)
importer.Update()

def flip_yaxis_texture_coords(polydata):
    tcoords = polydata.GetPointData().GetTCoords()
    flippedTcoords = vtk.vtkFloatArray()
    flippedTcoords.SetNumberOfComponents(2)
    flippedTcoords.SetName("TextureCoordinates")
    for i in range(tcoords.GetNumberOfTuples()):
        tc = tcoords.GetTuple2(i)
        flipped_tc = [tc[0], 1.0 - tc[1]]
        flippedTcoords.InsertNextTuple(flipped_tc)
    polydata.GetPointData().SetTCoords(flippedTcoords)

def applyTextures(actors):
    actors.InitTraversal()
    actor = actors.GetNextActor()
    while actor is not None:
        mapper = actor.GetMapper()
        if mapper:
            polydata = mapper.GetInputAsDataSet()
            if isinstance(polydata, vtk.vtkPolyData):
                property = actor.GetProperty()
                texture = property.GetTexture("albedoTex")
                if texture and polydata.GetPointData().GetTCoords() is not None:
                    flip_yaxis_texture_coords(polydata)
                    mapper.SetInputData(polydata)
                    actor.SetTexture(texture)
                    actor.SetMapper(mapper)
                actor = actors.GetNextActor()

actors = renderer.GetActors()
applyTextures(actors)

exporter = vtk.vtkGLTFExporter()
exporter.InlineDataOn()
exporter.SetFileName(OUTPUT_FILE)
exporter.SetRenderWindow(renderWindow)

exporter.Write()