ImplicitAnnulusWidget

#include <vtkActor.h>
#include <vtkAnnulus.h>
#include <vtkAppendPolyData.h>
#include <vtkCamera.h>
#include <vtkCameraOrientationWidget.h>
#include <vtkClipPolyData.h>
#include <vtkCommand.h>
#include <vtkConeSource.h>
#include <vtkGlyph3D.h>
#include <vtkImplicitAnnulusRepresentation.h>
#include <vtkImplicitAnnulusWidget.h>
#include <vtkInteractorStyleSwitch.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkSmartPointer.h>
#include <vtkSphereSource.h>
#include <vtkXMLPolyDataReader.h>

#include <algorithm>
#include <vector>

namespace {
// This does the actual work: updates the vtkAnnulus implicit function.
// This in turn causes the pipeline to update and clip the object.
// Callback for the interaction
class vtkTICWCallback : public vtkCommand
{
public:
  static vtkTICWCallback* New()
  {
    return new vtkTICWCallback;
  }

  void Execute(vtkObject* caller, unsigned long, void*) override
  {
    vtkImplicitAnnulusWidget* annulusWidget =
        reinterpret_cast<vtkImplicitAnnulusWidget*>(caller);
    vtkImplicitAnnulusRepresentation* rep =
        reinterpret_cast<vtkImplicitAnnulusRepresentation*>(
            annulusWidget->GetRepresentation());
    rep->GetAnnulus(this->Annulus);
    this->Actor->VisibilityOn();
  }

  vtkAnnulus* Annulus{nullptr};
  vtkActor* Actor{nullptr};
};

vtkNew<vtkAppendPolyData> CreateMace();

} // namespace

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

  vtkNew<vtkNamedColors> colors;

  vtkNew<vtkXMLPolyDataReader> reader;

  // This portion of the code clips the mace or the input from the reader with
  //  the vtkAnnulus implicit function. The clipped region is colored green.
  vtkNew<vtkAnnulus> annulus;
  vtkNew<vtkClipPolyData> clipper;
  clipper->SetClipFunction(annulus);
  clipper->InsideOutOn();

  vtkSmartPointer<vtkPolyData> source;
  if (argc < 2)
  {
    auto mace = CreateMace();
    source = mace->GetOutput();
  }
  else
  {
    // For example: cow.vtp
    reader->SetFileName(argv[1]);
    reader->Update();
    source = reader->GetOutput();
  }
  clipper->SetInputData(source);
  auto bounds = source->GetBounds();

  std::cout << "bounds: (";
  for (auto i = 0; i < 6; ++i)
  {
    if (i == 0)
    {
      std::cout << bounds[i];
    }
    else
    {
      std::cout << " " << bounds[i];
    }
  }
  std::cout << ")" << std::endl;

  vtkNew<vtkPolyDataMapper> mapper;
  mapper->SetInputData(source);

  vtkNew<vtkProperty> backFaces;
  backFaces->SetDiffuseColor(colors->GetColor3d("Gold").GetData());

  vtkNew<vtkActor> actor;
  actor->SetBackfaceProperty(backFaces);
  actor->SetMapper(mapper);
  actor->VisibilityOn();

  vtkNew<vtkPolyDataMapper> selectMapper;
  selectMapper->SetInputConnection(clipper->GetOutputPort());

  vtkNew<vtkActor> selectActor;
  selectActor->SetMapper(selectMapper);
  selectActor->GetProperty()->SetColor(colors->GetColor3d("Lime").GetData());
  selectActor->VisibilityOff();
  selectActor->SetScale(1.01, 1.01, 1.01);

  // Create the RenderWindow, Renderer and both Actors
  vtkNew<vtkRenderer> renderer;
  renderer->AddActor(actor);
  renderer->AddActor(selectActor);
  renderer->SetBackground(colors->GetColor3d("MidnightBlue").GetData());

  vtkNew<vtkRenderWindow> renWin;
  renWin->SetMultiSamples(0);
  renWin->SetSize(600, 600);
  renWin->SetWindowName("ImplicitAnnulusWidget");
  renWin->AddRenderer(renderer);

  vtkNew<vtkRenderWindowInteractor> iren;
  renWin->SetInteractor(iren);
  auto is = vtkInteractorStyleSwitch::SafeDownCast(iren->GetInteractorStyle());
  if (is)
  {
    is->SetCurrentStyleToTrackballCamera();
  }

  // The SetInteractor method is how 3D widgets are associated with the render
  // window interactor. Internally, SetInteractor sets up a bunch of callbacks
  // using the Command/Observer mechanism (AddObserver()).
  vtkNew<vtkTICWCallback> myCallback;
  myCallback->Annulus = annulus;
  myCallback->Actor = selectActor;

  std::vector<double> radii;
  for (auto i = 1; i < 6; i += 2)
  {
    radii.push_back((bounds[i] - bounds[i - 1]) / 2.0);
  }
  auto radius = *std::min_element(radii.cbegin(), radii.cend());

  vtkNew<vtkImplicitAnnulusRepresentation> rep;
  rep->SetPlaceFactor(1.25);
  rep->ScaleEnabledOff();
  rep->PlaceWidget(bounds);
  rep->SetInnerRadius(radius * 0.5);
  rep->SetOuterRadius(radius);
  std::cout << "Inner radius: " << rep->GetInnerRadius() << std::endl;
  std::cout << "Outer radius: " << rep->GetOuterRadius() << std::endl;

  vtkNew<vtkImplicitAnnulusWidget> annulusWidget;
  annulusWidget->SetInteractor(iren);
  annulusWidget->SetRepresentation(rep);
  annulusWidget->AddObserver(vtkCommand::InteractionEvent, myCallback);
  annulusWidget->EnabledOn();

  renderer->GetActiveCamera()->Azimuth(60);
  renderer->GetActiveCamera()->Elevation(30);
  renderer->ResetCamera();
  renderer->GetActiveCamera()->Zoom(1.0);

  vtkNew<vtkCameraOrientationWidget> cow;
  cow->SetParentRenderer(renderer);
  // Enable the widget.
  cow->On();

  // Render and interact.
  iren->Initialize();
  renWin->Render();
  annulusWidget->On();

  // Begin mouse interaction.
  iren->Start();

  return EXIT_SUCCESS;
}

namespace {
vtkNew<vtkAppendPolyData> CreateMace()
{
  // Create a mace out of filters.
  vtkNew<vtkSphereSource> sphere;
  vtkNew<vtkConeSource> coneSource;
  vtkNew<vtkGlyph3D> glyph;
  glyph->SetInputConnection(sphere->GetOutputPort());
  glyph->SetSourceConnection(coneSource->GetOutputPort());
  glyph->SetVectorModeToUseNormal();
  glyph->SetScaleModeToScaleByVector();
  glyph->SetScaleFactor(0.25);

  // The sphere and spikes are appended into a single polydata.
  // This just makes things simpler to manage.
  vtkNew<vtkAppendPolyData> apd;
  apd->AddInputConnection(glyph->GetOutputPort());
  apd->AddInputConnection(sphere->GetOutputPort());
  apd->Update();

  return apd;
}
} // namespace

cmake_minimum_required(VERSION 3.12 FATAL_ERROR)

project(ImplicitAnnulusWidget)

find_package(VTK COMPONENTS 
  CommonColor
  CommonCore
  CommonDataModel
  FiltersCore
  FiltersSources
  IOXML
  InteractionStyle
  InteractionWidgets
  RenderingContextOpenGL2
  RenderingCore
  RenderingFreeType
  RenderingGL2PSOpenGL2
  RenderingOpenGL2
)

if (NOT VTK_FOUND)
  message(FATAL_ERROR "ImplicitAnnulusWidget: Unable to find the VTK build folder.")
endif()

# Prevent a "command line is too long" failure in Windows.
set(CMAKE_NINJA_FORCE_RESPONSE_FILE "ON" CACHE BOOL "Force Ninja to use response files.")
add_executable(ImplicitAnnulusWidget MACOSX_BUNDLE ImplicitAnnulusWidget.cxx )
  target_link_libraries(ImplicitAnnulusWidget PRIVATE ${VTK_LIBRARIES}
)
# vtk_module_autoinit is needed
vtk_module_autoinit(
  TARGETS ImplicitAnnulusWidget
  MODULES ${VTK_LIBRARIES}
)

cd ImplicitAnnulusWidget/build

cmake ..

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

make

./ImplicitAnnulusWidget