VisualDebugging

#include <vtkSphereSource.h>
#include <vtkObjectFactory.h>
#include <vtkCommand.h>
#include <vtkPolyData.h>
#include <vtkSmartPointer.h>
#include <vtkPolyDataMapper.h>
#include <vtkActor.h>
#include <vtkRenderWindow.h>
#include <vtkRenderer.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkInteractorStyleTrackballCamera.h>

#include <vtkTestFilter.h>

class CustomStyle : public vtkInteractorStyleTrackballCamera
{
  public:
    static CustomStyle* New();
    vtkTypeMacro(CustomStyle, vtkInteractorStyleTrackballCamera);

    CustomStyle()
    {
      this->Actor = vtkSmartPointer<vtkActor>::New();
      this->Mapper = vtkSmartPointer<vtkPolyDataMapper>::New();
      this->Filter = vtkSmartPointer<vtkTestFilter>::New();
    }

    void CallbackFunction(vtkObject* caller,
                    long unsigned int eventId,
                    void* callData )
    {
      std::cout << "CustomStyle::CallbackFunction called." << std::endl;
      vtkPolyData* intermediate = this->Filter->GetIntermediateOutput();
      intermediate->Modified();
      this->Mapper->SetInput(intermediate);
      this->Renderer->ResetCamera();
      this->Renderer->Render();
      this->Interactor->GetRenderWindow()->Render();
    }

    void OnKeyPress()
    {
      // Get the keypress
      std::string key = this->Interactor->GetKeySym();

      if(key == "s") // 'S'tart
      {
        this->Renderer->AddActor(this->Actor);
        this->Filter->AddObserver(this->Filter->RefreshEvent, this, &CustomStyle::CallbackFunction);
        this->Filter->Update();

        this->Actor->SetMapper(this->Mapper);
      }

      // Forward events
      vtkInteractorStyleTrackballCamera::OnKeyPress();
    }

  vtkRenderer* Renderer;
  vtkSmartPointer<vtkActor> Actor;
  vtkSmartPointer<vtkPolyDataMapper> Mapper;
  vtkSmartPointer<vtkTestFilter> Filter;

};
vtkStandardNewMacro(CustomStyle);

int main(int argc, char *argv[])
{
  // Create a renderer, render window, and interactor
  vtkSmartPointer<vtkRenderer> renderer =
    vtkSmartPointer<vtkRenderer>::New();
  vtkSmartPointer<vtkRenderWindow> renderWindow =
    vtkSmartPointer<vtkRenderWindow>::New();
  renderWindow->AddRenderer(renderer);
  vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
    vtkSmartPointer<vtkRenderWindowInteractor>::New();
  renderWindowInteractor->SetRenderWindow(renderWindow);

  renderer->SetBackground(1,1,1); // White

  vtkSmartPointer<CustomStyle> style =
    vtkSmartPointer<CustomStyle>::New();
  style->Renderer = renderer;

  renderWindowInteractor->SetInteractorStyle(style);
  renderWindow->Render();
  renderWindowInteractor->Start();

  return EXIT_SUCCESS;
}

#include <vtkTestFilter.h>

#include <vtkObjectFactory.h>
#include <vtkCommand.h>
#include <vtkStreamingDemandDrivenPipeline.h>
#include <vtkInformationVector.h>
#include <vtkInformation.h>
#include <vtkDataObject.h>
#include <vtkSmartPointer.h>
#include <vtkAppendPolyData.h>
#include <vtkSphereSource.h>

vtkStandardNewMacro(vtkTestFilter);

vtkTestFilter::vtkTestFilter()
{
  this->SetNumberOfInputPorts(0);
  this->Output = vtkSmartPointer<vtkPolyData>::New();

  this->RefreshEvent = vtkCommand::UserEvent + 1;

}

int vtkTestFilter::RequestData(vtkInformation *vtkNotUsed(request),
                                             vtkInformationVector **inputVector,
                                             vtkInformationVector *outputVector)
{
  // Get the info object
  vtkInformation *outInfo = outputVector->GetInformationObject(0);

  vtkPolyData *output = vtkPolyData::SafeDownCast(
      outInfo->Get(vtkDataObject::DATA_OBJECT()));

  this->Output->DeepCopy(output);

  for(unsigned int i = 0; i < 10; i++)
  {
    Iterate(i);
    this->InvokeEvent(this->RefreshEvent, NULL);
  }

  output->ShallowCopy(this->Output);

  return 1;
}

void vtkTestFilter::Iterate(unsigned int iteration)
{
  vtkSmartPointer<vtkSphereSource> sphereSource =
    vtkSmartPointer<vtkSphereSource>::New();
  sphereSource->SetCenter(iteration, 0, 0);
  sphereSource->SetRadius(0.2);
  sphereSource->Update();

  vtkSmartPointer<vtkAppendPolyData> appendFilter =
    vtkSmartPointer<vtkAppendPolyData>::New();
  appendFilter->AddInputConnection(this->Output->GetProducerPort());
  appendFilter->AddInputConnection(sphereSource->GetOutputPort());
  appendFilter->Update();

  this->Output->DeepCopy(appendFilter->GetOutput());
}

#ifndef __vtkTestFilter_h
#define __vtkTestFilter_h

#include <vtkPolyDataAlgorithm.h>
#include <vtkSmartPointer.h>

class vtkTestFilter : public vtkPolyDataAlgorithm
{
public:
  vtkTypeMacro(vtkTestFilter,vtkPolyDataAlgorithm);
  static vtkTestFilter *New();

  vtkPolyData* GetIntermediateOutput() {return this->Output;}

  int RefreshEvent;

protected:
  vtkTestFilter();

  int RequestData(vtkInformation *, vtkInformationVector **, vtkInformationVector *);

  void Iterate(unsigned int iteration);

  vtkSmartPointer<vtkPolyData> Output;
private:
  vtkTestFilter(const vtkTestFilter&);  // Not implemented.
  void operator=(const vtkTestFilter&);  // Not implemented.

};

#endif

cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

project(VisualDebugging)

find_package(VTK COMPONENTS 
  vtkCommonCore
  vtkCommonDataModel
  vtkFiltersSources
  vtkInteractionStyle
  vtkRenderingCore
  vtkRenderingFreeType
  vtkRenderingOpenGL2 QUIET)
if (NOT VTK_FOUND)
  message("Skipping VisualDebugging: ${VTK_NOT_FOUND_MESSAGE}")
  return ()
endif()
message (STATUS "VTK_VERSION: ${VTK_VERSION}")
if (VTK_VERSION VERSION_LESS "8.90.0")
  # old system
  include(${VTK_USE_FILE})
  add_executable(VisualDebugging MACOSX_BUNDLE VisualDebugging.cxx )
  target_link_libraries(VisualDebugging PRIVATE ${VTK_LIBRARIES})
else ()
  # include all components
  add_executable(VisualDebugging MACOSX_BUNDLE VisualDebugging.cxx )
  target_link_libraries(VisualDebugging PRIVATE ${VTK_LIBRARIES})
  # vtk_module_autoinit is needed
  vtk_module_autoinit(
    TARGETS VisualDebugging
    MODULES ${VTK_LIBRARIES}
    )
endif () 

cd VisualDebugging/build 

cmake ..

cmake -DVTK_DIR:PATH=/home/me/vtk_build ..

make

./VisualDebugging