[Solved] VTK 6.1 and Qt 5.3: 3D Objects in QVTKWidget with bad transparencies

Bullub

Base: Debian 7.5 Wheezy 64 bits - Qt 5.3 installed from Online Installer; VTK 6.1 successfully compiled and installed manually with Qt support.

Result: A 3D sphere is displayed in a 3D QVTK window. At first glance, It looks OK, but when sphere is rotated, several panels and parts of the sphere become transparent.

Description:

Tried the basic official example of VTK for Qt:

In main.cpp:

@#include <QApplication>

#include <vtkAutoInit.h>
VTK_MODULE_INIT(vtkRenderingOpenGL);
VTK_MODULE_INIT(vtkInteractionStyle);

#include <vtkSmartPointer.h>
#include <vtkSphereSource.h>
#include <vtkPolyDataMapper.h>
#include <vtkActor.h>
#include <vtkImageViewer.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkInteractorStyleImage.h>
#include <vtkRenderer.h>
#include <vtkJPEGReader.h>
#include <QVTKWidget.h>

int main(int argc, char *argv[])
{
QApplication a(argc, argv);

QVTKWidget widget;
  widget.resize(256,256);

  // Setup sphere
  vtkSmartPointer<vtkSphereSource> sphereSource =
      vtkSmartPointer<vtkSphereSource>::New();
  sphereSource->Update();
  vtkSmartPointer<vtkPolyDataMapper> sphereMapper =
      vtkSmartPointer<vtkPolyDataMapper>::New();
  sphereMapper->SetInputConnection(sphereSource->GetOutputPort());
  vtkSmartPointer<vtkActor> sphereActor =
      vtkSmartPointer<vtkActor>::New();
  sphereActor->SetMapper(sphereMapper);

  // Setup window
  vtkSmartPointer<vtkRenderWindow> renderWindow =
      vtkSmartPointer<vtkRenderWindow>::New();

  // Setup renderer
  vtkSmartPointer<vtkRenderer> renderer =
      vtkSmartPointer<vtkRenderer>::New();
  renderWindow->AddRenderer(renderer);

  renderer->AddActor(sphereActor);
  renderer->ResetCamera();

  widget.SetRenderWindow(renderWindow);
  widget.show();

return a.exec(&#41;;

}@

And significantly, RenderWindowUISingleInheritance gives same result.

Bullub

Thanks to StackOverflow, I got this question answered:

http://stackoverflow.com/questions/24131430/vtk-6-1-and-qt-5-3-3d-objects-in-qvtkwidget-with-bad-transparencies/24148669#24148669

The final code stands as follows:

@#include <vtkAutoInit.h>
VTK_MODULE_INIT(vtkRenderingOpenGL);
VTK_MODULE_INIT(vtkInteractionStyle);

#include <vtkSmartPointer.h>
#include <vtkSphereSource.h>
#include <vtkPolyDataMapper.h>
#include <vtkActor.h>
#include <vtkImageViewer.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkInteractorStyleImage.h>
#include <vtkRenderer.h>
#include <vtkJPEGReader.h>
#include <QVTKWidget.h>
#include <vtkProperty.h>

int main(int argc, char *argv[])
{
QApplication a(argc, argv);

QVTKWidget widget;
  widget.resize(256,256);

  // Setup sphere
  vtkSmartPointer<vtkSphereSource> sphereSource =
      vtkSmartPointer<vtkSphereSource>::New();
  sphereSource->Update();
  vtkSmartPointer<vtkPolyDataMapper> sphereMapper =
      vtkSmartPointer<vtkPolyDataMapper>::New();
  sphereMapper->SetInputConnection(sphereSource->GetOutputPort());
  vtkSmartPointer<vtkActor> sphereActor =
      vtkSmartPointer<vtkActor>::New();
  sphereActor->GetProperty()->SetFrontfaceCulling(true);
  sphereActor->SetMapper(sphereMapper);

  // Setup window
  vtkSmartPointer<vtkRenderWindow> renderWindow =
      vtkSmartPointer<vtkRenderWindow>::New();

  // Setup renderer
  vtkSmartPointer<vtkRenderer> renderer =
      vtkSmartPointer<vtkRenderer>::New();
  renderWindow->AddRenderer(renderer);

  renderer->AddActor(sphereActor);
  renderer->ResetCamera();

  widget.SetRenderWindow(renderWindow);
  widget.show();

return a.exec&#40;&#41;;

}@

Note the additions of:
@
#include <vtkProperty.h>@

and
@
sphereActor->GetProperty()->SetFrontfaceCulling(true);@