# An error about openxr demo?

**URL:** https://discourse.vtk.org/t/an-error-about-openxr-demo/10065
**Category:** VR/AR
**Created:** [December 5, 2022, 8:47am UTC](https://discourse.vtk.org/t/an-error-about-openxr-demo/10065 "2022-12-05T08:47:08Z")
**Posts on this page:** 4
**Page:** 1

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### Author: ![Rain-BBking](https://discourse.vtk.org/user_avatar/discourse.vtk.org/rain-bbking/32/6170_2.png) [@Rain-BBking](https://discourse.vtk.org/u/Rain-BBking)
#### Post date: [December 5, 2022, 8:47am UTC](https://discourse.vtk.org/t/an-error-about-openxr-demo/10065/1 "2022-12-05T08:47:08Z")

</div>

I’m writing a project recently that needs to achieve VR effect. I’m going to use vtkOpenXRRenderWindow to implement it, but I had a problem when I used the official demo( [Rendering/OpenXR/Testing/Cxx/TestOpenXRInitialization.cxx · v9.2.0 · VTK / VTK · GitLab (kitware.com)](https://gitlab.kitware.com/vtk/vtk/-/blob/v9.2.0/Rendering/OpenXR/Testing/Cxx/TestOpenXRInitialization.cxx)) for testing:

Connect oculus headset and run demo. I can only see the set background color in the headset, without any objects. Warning：No rendered is displayed in the prompt window.

 ![image](https://discourse.vtk.org/uploads/default/original/2X/9/9c91ab41d7004d49d10116592afca86e8ee2f6d2.png)

I don’t know what caused it. Does anyone know the reason?

Details are as follows:

```auto
#include "vtkCullerCollection.h"
#include "vtkLight.h"
#include "vtkNew.h"
#include "vtkOpenGLPolyDataMapper.h"
#include "vtkOpenGLVertexBufferObject.h"
#include "vtkOpenXRCamera.h"
#include "vtkOpenXRRenderWindow.h"
#include "vtkOpenXRRenderWindowInteractor.h"
#include "vtkOpenXRRenderer.h"
#include "vtkPLYReader.h"
#include "vtkProperty.h"
#include "vtkRegressionTestImage.h"
#include "vtkRenderWindowInteractor.h"
#include "vtkRenderer.h"
#include "vtkTestUtilities.h"
#include "vtkTransform.h"
#include "vtkTransformPolyDataFilter.h"

#include <memory>

int main()
{
	vtkNew<vtkOpenXRRenderer> renderer;
	renderer->SetShowFloor(true);

	vtkNew<vtkOpenXRRenderWindow> renderWindow;
	vtkNew<vtkOpenXRRenderWindowInteractor> iren;
	vtkNew<vtkOpenXRCamera> cam;

	renderer->SetBackground(0.2, 0.3, 0.4);
	renderWindow->AddRenderer(renderer);
	vtkNew<vtkActor> actor;
	renderer->AddActor(actor);
	iren->SetRenderWindow(renderWindow);
	renderer->SetActiveCamera(cam);

	renderer->RemoveCuller(renderer->GetCullers()->GetLastItem());

	vtkNew<vtkLight> light;
	light->SetLightTypeToSceneLight();
	light->SetPosition(1.0, 1.0, 1.0);
	renderer->AddLight(light);

	std::string filename = "D:/file/bunny/reconstruction/bun_zipper_res4.ply";   
	vtkSmartPointer<vtkPLYReader> reader = vtkSmartPointer<vtkPLYReader>::New();
	reader->SetFileName(filename.c_str());

	vtkNew<vtkTransform> trans;
	trans->Translate(20.0, 0.0, 0.0);
	trans->Scale(0.001, 0.001, 0.001);
	vtkNew<vtkTransformPolyDataFilter> tf;
	tf->SetOutputPointsPrecision(vtkAlgorithm::DOUBLE_PRECISION);
	tf->SetTransform(trans);
	tf->SetInputConnection(reader->GetOutputPort());

	vtkNew<vtkOpenGLPolyDataMapper> mapper;
	mapper->SetInputConnection(tf->GetOutputPort());
	mapper->SetVBOShiftScaleMethod(vtkOpenGLVertexBufferObject::AUTO_SHIFT_SCALE);
	actor->SetMapper(mapper);
	actor->GetProperty()->SetAmbientColor(0.2, 0.2, 1.0);
	actor->GetProperty()->SetDiffuseColor(1.0, 0.65, 0.7);
	actor->GetProperty()->SetSpecularColor(1.0, 1.0, 1.0);
	actor->GetProperty()->SetSpecular(0.5);
	actor->GetProperty()->SetDiffuse(0.7);
	actor->GetProperty()->SetAmbient(0.5);
	actor->GetProperty()->SetSpecularPower(20.0);
	actor->GetProperty()->SetOpacity(1.0);

	renderer->ResetCamera();

	iren->Start();

	return 0;
}
```

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<div class="post-metadata">

### Author: ![mwestphal](https://discourse.vtk.org/user_avatar/discourse.vtk.org/mwestphal/32/19_2.png) [@mwestphal](https://discourse.vtk.org/u/mwestphal)
#### Post date: [December 5, 2022, 8:48am UTC](https://discourse.vtk.org/t/an-error-about-openxr-demo/10065/2 "2022-12-05T08:48:04Z")

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@scottwittenburg @cory.quammen @Tiffany_Chhim @Thomas_Galland

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<div class="post-metadata">

### Author: ![scottwittenburg](https://discourse.vtk.org/user_avatar/discourse.vtk.org/scottwittenburg/32/5654_2.png) [@scottwittenburg](https://discourse.vtk.org/u/scottwittenburg)
#### Post date: [December 5, 2022, 5:35pm UTC](https://discourse.vtk.org/t/an-error-about-openxr-demo/10065/3 "2022-12-05T17:35:06Z")

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Hard to say without more information. Is SteamVR updated to the latest version and running? I don’t have an oculus headset, but as far as I’m aware, that should work fine.

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<div class="post-metadata">

### Author: ![Rain-BBking](https://discourse.vtk.org/user_avatar/discourse.vtk.org/rain-bbking/32/6170_2.png) [@Rain-BBking](https://discourse.vtk.org/u/Rain-BBking)
#### Post date: [December 6, 2022, 6:25am UTC](https://discourse.vtk.org/t/an-error-about-openxr-demo/10065/4 "2022-12-06T06:25:16Z")

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Thank you for your reply.

I tried to install steamVR, but the problem was not solved. I downloaded the official example of openxr for testing, and it was successfully displayed in the helmet. It should be explained that there should be no problem in hardware.