DataStructureComparison

#include <vtkActor.h>
#include <vtkCamera.h>
#include <vtkInteractorStyleTrackballCamera.h>
#include <vtkNew.h>
#include <vtkPointSource.h>
#include <vtkPolyData.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkSmartPointer.h>
#include <vtkXMLPolyDataReader.h>

#include <vtkKdTreePointLocator.h>
#include <vtkModifiedBSPTree.h>
#include <vtkOBBTree.h>
#include <vtkOctreePointLocator.h>

#include <vector>

namespace {
class KeyPressInteractorStyle : public vtkInteractorStyleTrackballCamera
{
public:
  static KeyPressInteractorStyle* New();
  vtkSmartPointer<vtkPolyData> data;
  std::vector<vtkRenderer*> renderers;
  std::vector<vtkSmartPointer<vtkLocator>> trees;
  std::vector<vtkSmartPointer<vtkPolyDataMapper>> mappers;
  std::vector<vtkSmartPointer<vtkActor>> actors;

  vtkSmartPointer<vtkPolyDataMapper> meshMapper;
  vtkSmartPointer<vtkActor> meshActor;

  void Initialize()
  {
    this->meshMapper->SetInputData(this->data);
    for (unsigned int i = 0; i < 4; i++)
    {
      vtkSmartPointer<vtkPolyDataMapper> mapper =
          vtkSmartPointer<vtkPolyDataMapper>::New();
      this->mappers.push_back(mapper);
      vtkSmartPointer<vtkActor> actor = vtkSmartPointer<vtkActor>::New();
      actor->SetMapper(mapper);
      actor->GetProperty()->SetRepresentationToWireframe();
      this->actors.push_back(actor);
      this->renderers[i]->AddActor(actor);

      this->renderers[i]->AddActor(meshActor);
    }
    this->Level = 1;
    std::cout << "Level = " << this->Level << std::endl;
    this->ReDraw();
  }

  KeyPressInteractorStyle()
  {
    this->Level = 1;

    vtkSmartPointer<vtkLocator> tree0 =
        vtkSmartPointer<vtkKdTreePointLocator>::New();
    this->trees.push_back(tree0);
    vtkSmartPointer<vtkLocator> tree1 = vtkSmartPointer<vtkOBBTree>::New();
    this->trees.push_back(tree1);
    vtkSmartPointer<vtkLocator> tree2 =
        vtkSmartPointer<vtkOctreePointLocator>::New();
    this->trees.push_back(tree2);
    vtkSmartPointer<vtkLocator> tree3 =
        vtkSmartPointer<vtkModifiedBSPTree>::New();
    this->trees.push_back(tree3);

    this->meshMapper = vtkSmartPointer<vtkPolyDataMapper>::New();
    this->meshActor = vtkSmartPointer<vtkActor>::New();
    this->meshActor->SetMapper(this->meshMapper);
  }

  virtual void OnChar()
  {
    char ch = this->Interactor->GetKeyCode();

    switch (ch)
    {
    case 'n':
      this->Level++;
      break;
    case 'p':
      if (this->Level > 1)
      {
        this->Level--;
      }
      break;
    default:
      std::cout << "An unhandled key was pressed." << std::endl;
      break;
    }

    this->ReDraw();

    // Forward events.
    if (ch != 'p') // Don't forward the "pick" command.
    {
      vtkInteractorStyleTrackballCamera::OnChar();
    }
  }

  void ReDraw()
  {

    std::cout << "Level " << this->Level << std::endl;
    for (unsigned i = 0; i < 4; i++)
    {

      vtkSmartPointer<vtkLocator> tree = this->trees[i];
      // vtkRenderer* renderer = this->renderers[i];

      tree->SetDataSet(data);
      tree->BuildLocator();

      vtkSmartPointer<vtkPolyData> polydata =
          vtkSmartPointer<vtkPolyData>::New();
      std::cout << "Tree " << i << " has " << tree->GetLevel() << " levels."
                << std::endl;

      if (this->Level > tree->GetLevel())
      {
        tree->GenerateRepresentation(tree->GetLevel(), polydata);
      }
      else
      {
        tree->GenerateRepresentation(this->Level, polydata);
      }

      this->mappers[i]->SetInputData(polydata);
    }

    this->Interactor->GetRenderWindow()->Render();
  }

private:
  int Level;
};

vtkStandardNewMacro(KeyPressInteractorStyle);

} // namespace

int main(int argc, char* argv[])
{
  vtkNew<vtkPolyData> originalMesh;

  if (argc > 1) // If a file name is specified, open and use the file.
  {
    vtkNew<vtkXMLPolyDataReader> reader;
    reader->SetFileName(argv[1]);
    reader->Update();
    originalMesh->ShallowCopy(reader->GetOutput());
  }
  else // If a file name is not specified, create a random cloud of points.
  {
    vtkNew<vtkPointSource> sphereSource;
    sphereSource->SetNumberOfPoints(1000);

    sphereSource->Update();
    originalMesh->ShallowCopy(sphereSource->GetOutput());
  }

  double numberOfViewports = 4.;

  vtkNew<vtkRenderWindow> renderWindow;
  renderWindow->SetSize(200 * numberOfViewports, 200); //(width, height)
  renderWindow->SetWindowName("DataStructureComparison");

  vtkNew<KeyPressInteractorStyle> style;
  style->data = originalMesh;

  vtkNew<vtkCamera> camera;

  for (unsigned int i = 0; i < 4; i++)
  {
    vtkNew<vtkRenderer> renderer;
    renderWindow->AddRenderer(renderer);
    style->renderers.push_back(renderer);
    renderer->SetViewport(static_cast<double>(i) / numberOfViewports, 0,
                          static_cast<double>(i + 1) / numberOfViewports, 1);
    renderer->SetBackground(0.2, 0.3, 0.4);
    renderer->SetActiveCamera(camera);
  }

  vtkNew<vtkRenderWindowInteractor> renderWindowInteractor;
  renderWindowInteractor->SetRenderWindow(renderWindow);
  renderWindowInteractor->SetInteractorStyle(style);
  style->Initialize();
  style->renderers[0]->ResetCamera();

  renderWindowInteractor->Start();

  return EXIT_SUCCESS;
}

cmake_minimum_required(VERSION 3.12 FATAL_ERROR)

project(DataStructureComparison)

find_package(VTK COMPONENTS 
  CommonCore
  CommonDataModel
  FiltersFlowPaths
  FiltersGeneral
  FiltersSources
  IOXML
  InteractionStyle
  RenderingContextOpenGL2
  RenderingCore
  RenderingFreeType
  RenderingGL2PSOpenGL2
  RenderingOpenGL2
)

if (NOT VTK_FOUND)
  message(FATAL_ERROR "DataStructureComparison: 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(DataStructureComparison MACOSX_BUNDLE DataStructureComparison.cxx )
  target_link_libraries(DataStructureComparison PRIVATE ${VTK_LIBRARIES}
)
# vtk_module_autoinit is needed
vtk_module_autoinit(
  TARGETS DataStructureComparison
  MODULES ${VTK_LIBRARIES}
)

cd DataStructureComparison/build

cmake ..

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

make

./DataStructureComparison