# How to render a GLTF model correctly

**URL:** https://discourse.vtk.org/t/how-to-render-a-gltf-model-correctly/3938
**Category:** Support
**Created:** [August 9, 2020, 4:57am UTC](https://discourse.vtk.org/t/how-to-render-a-gltf-model-correctly/3938 "2020-08-09T04:57:57Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![yuhuimoon](https://discourse.vtk.org/letter_avatar_proxy/v4/letter/y/c6cbf5/32.png) [@yuhuimoon](https://discourse.vtk.org/u/yuhuimoon)
#### Post date: [August 9, 2020, 4:57am UTC](https://discourse.vtk.org/t/how-to-render-a-gltf-model-correctly/3938/1 "2020-08-09T04:57:58Z")

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Hi everyone,  
I have compiled and built VTK 9.0.1 successfully. I want to load a gltf model. It’s a cube exported from blender2.8 and it can be render in other gltf viewer. I use **vtkGLTFReader**. I can get **nbScenes** and **nbAnimations** correctly, but there’s nothing in the scene. Here’s part of my code:

```
vtkSmartPointer<vtkGLTFReader> gltfReader = vtkSmartPointer<vtkGLTFReader>::New();
gltfReader->SetFileName("E:/CodeProjects/GLTF/models/cube01.gltf");
gltfReader->Update();

vtkIdType nbScenes = gltfReader->GetNumberOfScenes();
vtkIdType nbAnimations = gltfReader->GetNumberOfAnimations();

vtkSmartPointer<vtkPolyDataMapper> polyDataMapper = vtkSmartPointer<vtkPolyDataMapper>::New();
polyDataMapper->SetInputConnection(gltfReader->GetOutputPort());

vtkSmartPointer<vtkActor> actor = vtkSmartPointer<vtkActor>::New();
actor->SetMapper(polyDataMapper);

vtkSmartPointer<vtkRenderWindow> rw = vtkSmartPointer<vtkRenderWindow>::New();
rw->SetSize(800, 600);
rw->SetWindowName("GlTF Demo");

vtkSmartPointer<vtkRenderer> render = vtkSmartPointer<vtkRenderer>::New();
render->AddActor(actor);
rw->AddRenderer(render);

vtkSmartPointer<vtkRenderWindowInteractor> rwi = vtkSmartPointer<vtkRenderWindowInteractor>::New();
rwi->SetRenderWindow(rw);

vtkSmartPointer<vtkInteractorStyleTrackballCamera> style = vtkSmartPointer<vtkInteractorStyleTrackballCamera>::New();
rwi->SetInteractorStyle(style);

rw->Render();
rwi->Start();

```

Can anyone give me some tips? Thanks in advance.

---

<div class="post-metadata">

### Author: ![yuhuimoon](https://discourse.vtk.org/letter_avatar_proxy/v4/letter/y/c6cbf5/32.png) [@yuhuimoon](https://discourse.vtk.org/u/yuhuimoon)
#### Post date: [August 9, 2020, 8:40am UTC](https://discourse.vtk.org/t/how-to-render-a-gltf-model-correctly/3938/2 "2020-08-09T08:40:44Z")

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I use the following code and the model is loaded successfully.

```
vtkSmartPointer<vtkCompositePolyDataMapper2> polyDataMapper = vtkSmartPointer<vtkCompositePolyDataMapper2>::New();
polyDataMapper->SetInputConnection(gltfReader->GetOutputPort());

```

instead of:

```
vtkSmartPointer<vtkPolyDataMapper> polyDataMapper = vtkSmartPointer<vtkPolyDataMapper>::New();
polyDataMapper->SetInputConnection(gltfReader->GetOutputPort());
```