VTK/Examples/Cxx/Utilities/DetermineActorType

DetermineActorType.cxx

#include <vtkSmartPointer.h>

#include <vtkActor.h>
#include <vtkActorCollection.h>
#include <vtkCubeAxesActor.h>
#include <vtkPolyData.h>
#include <vtkPolyDataMapper.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkSphereSource.h>

int main(int, char *[])
{
  // Sphere
  vtkSmartPointer<vtkSphereSource> sphereSource = 
    vtkSmartPointer<vtkSphereSource>::New();
  sphereSource->Update();
  
  vtkSmartPointer<vtkPolyDataMapper> mapper = 
    vtkSmartPointer<vtkPolyDataMapper>::New();
  mapper->SetInputConnection(sphereSource->GetOutputPort());
  
  vtkSmartPointer<vtkActor> actor = 
    vtkSmartPointer<vtkActor>::New();
  actor->SetMapper(mapper);
  
  // Cube axes
  vtkSmartPointer<vtkCubeAxesActor> cubeAxesActor = 
    vtkSmartPointer<vtkCubeAxesActor>::New();
  
  // Create a renderer and render window
  vtkSmartPointer<vtkRenderer> renderer = 
    vtkSmartPointer<vtkRenderer>::New();
  cubeAxesActor->SetCamera(renderer->GetActiveCamera());
  
  renderer->AddActor(actor);
  renderer->AddActor(cubeAxesActor);
  
  // Determine the types of the actors - method 1
  {
  std::cout << "Method 1:" << std::endl;
  vtkActorCollection* actorCollection = renderer->GetActors();
  actorCollection->InitTraversal();

  for(vtkIdType i = 0; i < actorCollection->GetNumberOfItems(); i++)
    {
    vtkActor* nextActor = actorCollection->GetNextActor();
    std::cout << "nextActor " << i << " : " << nextActor->GetClassName() << std::endl;
    std::string className = nextActor->GetClassName();
    std::string wantedClass = "vtkCubeAxesActor";
    if(className == wantedClass)
      {
      std::cout << "nextActor " << i << " is a vtkCubeAxesActor!" << std::endl;
      }
    else
      {
      std::cout << "nextActor " << i << " is NOT a vtkCubeAxesActor!" << std::endl;
      }
    }
  }
  
  // Determine the types of the actors - method 2
  {
  std::cout << "Method 2:" << std::endl;
  vtkActorCollection* actorCollection = renderer->GetActors();
  actorCollection->InitTraversal();

  for(vtkIdType i = 0; i < actorCollection->GetNumberOfItems(); i++)
    {
    vtkActor* nextActor = actorCollection->GetNextActor();
    std::cout << "nextActor " << i << " : " << nextActor->GetClassName() << std::endl;
    if(nextActor->IsA("vtkCubeAxesActor"))
      {
      std::cout << "nextActor " << i << " is a vtkCubeAxesActor!" << std::endl;
      }
    else
      {
      std::cout << "nextActor " << i << " is NOT a vtkCubeAxesActor!" << std::endl;
      }
    }
  }
  
  // Determine the types of the actors - method 3
  {
  std::cout << "Method 3:" << std::endl;
  vtkActorCollection* actorCollection = renderer->GetActors();
  actorCollection->InitTraversal();

  for(vtkIdType i = 0; i < actorCollection->GetNumberOfItems(); i++)
    {
    vtkActor* nextActor = actorCollection->GetNextActor();
    std::cout << "nextActor " << i << " : " << nextActor->GetClassName() << std::endl;

    if(vtkCubeAxesActor::SafeDownCast(nextActor) != 0)
      {
      std::cout << "nextActor " << i << " is a vtkCubeAxesActor!" << std::endl;
      }
    else
      {
      std::cout << "nextActor " << i << " is NOT a vtkCubeAxesActor!" << std::endl;
      }
    }
  }
  
  // Determine the types of the actors - method 4
  {
  std::cout << "Method 4:" << std::endl;
  vtkActorCollection* actorCollection = renderer->GetActors();
  actorCollection->InitTraversal();

  for(vtkIdType i = 0; i < actorCollection->GetNumberOfItems(); i++)
    {
    vtkActor* nextActor = actorCollection->GetNextActor();
    std::cout << "nextActor " << i << " : " << nextActor->GetClassName() << std::endl;

    if(dynamic_cast<vtkCubeAxesActor*>(nextActor) != 0)
      {
      std::cout << "nextActor " << i << " is a vtkCubeAxesActor!" << std::endl;
      }
    else
      {
      std::cout << "nextActor " << i << " is NOT a vtkCubeAxesActor!" << std::endl;
      }
    }
  }
 
  // Render the scene
  vtkSmartPointer<vtkRenderWindow> renderWindow = 
    vtkSmartPointer<vtkRenderWindow>::New();
  renderWindow->AddRenderer(renderer);

  vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor = 
    vtkSmartPointer<vtkRenderWindowInteractor>::New();
  renderWindowInteractor->SetRenderWindow(renderWindow);

  renderer->ResetCamera();
  renderWindow->Render();
  renderWindowInteractor->Initialize();
  renderWindowInteractor->Start();
  
  return EXIT_SUCCESS;
}

Please try the new VTKExamples website.

CMakeLists.txt

cmake_minimum_required(VERSION 2.8)

PROJECT(DetermineActorType)

find_package(VTK REQUIRED)
include(${VTK_USE_FILE})

add_executable(DetermineActorType MACOSX_BUNDLE DetermineActorType.cxx)

if(VTK_LIBRARIES)
  target_link_libraries(DetermineActorType ${VTK_LIBRARIES})
else()
  target_link_libraries(DetermineActorType vtkHybrid vtkWidgets)
endif()

Download and Build DetermineActorType

Click here to download DetermineActorType. and its CMakeLists.txt file.

Once the tarball DetermineActorType.tar has been downloaded and extracted,

cd DetermineActorType/build 

• If VTK is installed:

cmake ..

• If VTK is not installed but compiled on your system, you will need to specify the path to your VTK build:

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

Build the project:

make

and run it:

./DetermineActorType

WINDOWS USERS PLEASE NOTE: Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.

It isn't clear what this example is demonstrating - the use of CubeAxesActor is confusing.