PolygonalSurfacePointPlacer

#include <vtkSmartPointer.h>
#include <vtkCommand.h>
#include <vtkProperty.h>
#include <vtkContourWidget.h>
#include <vtkSphereSource.h>
#include <vtkPolyDataMapper.h>
#include <vtkActor.h>
#include <vtkRenderer.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkPolyDataCollection.h>
#include <vtkPolygonalSurfacePointPlacer.h>
#include <vtkOrientedGlyphContourRepresentation.h>

class MyCallback : public vtkCommand
{
  public:
    static MyCallback *New()
    {
      return new MyCallback;
    }
    MyCallback(){}

    virtual void Execute(vtkObject *caller, unsigned long, void*)
    {
      vtkContourWidget *contourWidget = reinterpret_cast<vtkContourWidget*>(caller);
      vtkContourRepresentation* rep = static_cast<vtkContourRepresentation *>(contourWidget->GetRepresentation());
      std::cout << "There are " << rep->GetNumberOfNodes() << " nodes." << std::endl;
    }

  void SetSphereSource(vtkSmartPointer<vtkSphereSource> sphere) {this->SphereSource = sphere;}

  private:
    vtkSmartPointer<vtkSphereSource> SphereSource;
};

int main(int, char *[])
{
  vtkSmartPointer<vtkSphereSource> sphereSource = 
    vtkSmartPointer<vtkSphereSource>::New();
  sphereSource->SetRadius(5);
  sphereSource->Update();

  vtkSmartPointer<vtkPolyDataMapper> mapper = 
    vtkSmartPointer<vtkPolyDataMapper>::New();
  mapper->SetInputConnection(sphereSource->GetOutputPort());

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

  // Create the RenderWindow, Renderer
  vtkSmartPointer<vtkRenderer> renderer = 
    vtkSmartPointer<vtkRenderer>::New();
  vtkSmartPointer<vtkRenderWindow> renderWindow = 
    vtkSmartPointer<vtkRenderWindow>::New();
  renderWindow->AddRenderer(renderer);
  vtkSmartPointer<vtkRenderWindowInteractor> interactor = 
    vtkSmartPointer<vtkRenderWindowInteractor>::New();
  interactor->SetRenderWindow(renderWindow);

  renderer->AddActor(actor);

  vtkSmartPointer<vtkContourWidget> contourWidget = 
    vtkSmartPointer<vtkContourWidget>::New();
  contourWidget->SetInteractor(interactor);


  vtkSmartPointer<MyCallback> callback = 
    vtkSmartPointer<MyCallback>::New();
  callback->SetSphereSource(sphereSource);
  contourWidget->AddObserver(vtkCommand::InteractionEvent,callback);

  vtkOrientedGlyphContourRepresentation* rep = 
    vtkOrientedGlyphContourRepresentation::SafeDownCast(
    contourWidget->GetRepresentation());

  vtkSmartPointer<vtkPolygonalSurfacePointPlacer> pointPlacer =
    vtkSmartPointer<vtkPolygonalSurfacePointPlacer>::New();
  pointPlacer->AddProp(actor);
  pointPlacer->GetPolys()->AddItem(sphereSource->GetOutput());

  rep->GetLinesProperty()->SetColor(1, 0, 0);
  rep->GetLinesProperty()->SetLineWidth(3.0);
  rep->SetPointPlacer(pointPlacer);

  contourWidget->EnabledOn();
  renderer->ResetCamera();
  renderWindow->Render();
  interactor->Initialize();

  interactor->Start();

  return EXIT_SUCCESS;
}

cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

project(PolygonalSurfacePointPlacer)

find_package(VTK COMPONENTS 
  vtkCommonCore
  vtkCommonDataModel
  vtkFiltersSources
  vtkInteractionStyle
  vtkInteractionWidgets
  vtkRenderingCore
  vtkRenderingFreeType
  vtkRenderingOpenGL2 QUIET)
if (NOT VTK_FOUND)
  message("Skipping PolygonalSurfacePointPlacer: ${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(PolygonalSurfacePointPlacer MACOSX_BUNDLE PolygonalSurfacePointPlacer.cxx )
  target_link_libraries(PolygonalSurfacePointPlacer PRIVATE ${VTK_LIBRARIES})
else ()
  # include all components
  add_executable(PolygonalSurfacePointPlacer MACOSX_BUNDLE PolygonalSurfacePointPlacer.cxx )
  target_link_libraries(PolygonalSurfacePointPlacer PRIVATE ${VTK_LIBRARIES})
  # vtk_module_autoinit is needed
  vtk_module_autoinit(
    TARGETS PolygonalSurfacePointPlacer
    MODULES ${VTK_LIBRARIES}
    )
endif () 

cd PolygonalSurfacePointPlacer/build 

cmake ..

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

make

./PolygonalSurfacePointPlacer