# I am getting segmentation fault with EGL offscreen rendering window

**URL:** <https://discourse.vtk.org/t/i-am-getting-segmentation-fault-with-egl-offscreen-rendering-window/12970>\
**Category:** Development\
**Created:** [December 26, 2023, 10:53pm UTC](https://discourse.vtk.org/t/i-am-getting-segmentation-fault-with-egl-offscreen-rendering-window/12970 "2023-12-26T22:53:45Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![Rafael\_Scatena](https://discourse.vtk.org/user_avatar/discourse.vtk.org/rafael_scatena/32/7820_2.png) [@Rafael\_Scatena](https://discourse.vtk.org/u/Rafael_Scatena)\
**Post date:** [December 26, 2023, 10:53pm UTC](https://discourse.vtk.org/t/i-am-getting-segmentation-fault-with-egl-offscreen-rendering-window/12970/1 "2023-12-26T22:53:45Z")

</div>

Here is my code and the error message.

Thank you for the assistance.

Rafael S.

```
   std::cerr << "Colours" << std::endl;	              
   vtkNew<vtkNamedColors> colors;
    

   // Create a sphere
   vtkNew<vtkSphereSource> sphereSource;
    sphereSource->SetThetaResolution(75);
    sphereSource->SetPhiResolution(75);

  
  std::cerr << "Sphere Created Ok" << std::endl;	  
  // Create a mapper and actor
  vtkNew<vtkPolyDataMapper> mapper;
  mapper->SetInputConnection(sphereSource->GetOutputPort());

  // Apply the texture
  vtkNew<vtkTexture> texture;
  texture->SetInputConnection(sphereSource->GetOutputPort());

  vtkNew<vtkActor> actor;
  actor->SetMapper(mapper);
  actor->GetProperty()->SetColor(colors->GetColor3d("White").GetData());
  actor->SetTexture(texture);

  // A renderer and render window
  vtkNew<vtkRenderer> renderer;
  renderer->AddActor(actor);
  renderer->SetBackground(colors->GetColor3d("SlateGray").GetData());
  
  vtkNew<vtkEGLRenderWindow> renderWindow;
  std::cerr << "Number of Devices: "<< renderWindow->GetNumberOfDevices() << std::endl;	  
  renderWindow->MakeCurrent();
  renderWindow->OffScreenRenderingOn();
  renderWindow->SetShowWindow(false);
  renderWindow->WindowInitialize();
  renderWindow->AddRenderer(renderer);

  std::cerr << "Render Created Ok" << std::endl;

  
  // Add the actors to the scene
  
  // Perform offscreen rendering

  std::cerr << "Actor Added Ok" << std::endl;

  std::cerr << "Render Ok" << std::endl;

  vtkNew<vtkWindowToImageFilter> windowToImageFilter;
  windowToImageFilter->SetInput(renderWindow);
  windowToImageFilter->Update();
  
  std::cerr << "Render-Window to image Ok" << std::endl;
  

  vtkNew<vtkPNGWriter> writer;
  writer->SetFileName("/home/3484681/Área de Trabalho/PRISMAMESH/createmesh/screenshot.png");
  writer->SetInputConnection(windowToImageFilter->GetOutputPort());
  writer->Write();
  
  std::cerr << "Write Ok" << std::endl;
  
Sphere Created Ok
Number of Devices: 3
2023-12-26 19:48:40.841 ( 0.586s) [7FBCADE4D5C0] vtkEGLRenderWindow.cxx:340 WARN| vtkEGLRenderWindow (0x56173903cd40): EGL device index: 3 could not be initialized. Trying other devices...
Render Created Ok
Actor Added Ok
Render Ok
Falha de segmentação

```

---

<div class="post-metadata">

**Author:** ![ben.boeckel](https://discourse.vtk.org/letter_avatar_proxy/v4/letter/b/ea5d25/32.png) [@ben.boeckel](https://discourse.vtk.org/u/ben.boeckel)\
**Post date:** [December 26, 2023, 11:25pm UTC](https://discourse.vtk.org/t/i-am-getting-segmentation-fault-with-egl-offscreen-rendering-window/12970/2 "2023-12-26T23:25:37Z")

</div>

Please do not repost questions; it is the holidays and not everyone is around to answer questions. Reposts just create even more load for those to go through when they get back.

Repost of: [Atempt to render offscreen using vtkEGLRenderWindow](https://discourse.vtk.org/t/atempt-to-render-offscreen-using-vtkeglrenderwindow/12956)