# PointCellIds

VTKExamples/Cxx/PolyData/PointCellIds

### Code

PointCellIds.cxx

    #include <vtkSmartPointer.h>
    #include <vtkSphereSource.h>
    #include <vtkIdFilter.h>
    #include <vtkIdTypeArray.h>
    #include <vtkPointData.h>
    #include <vtkCellData.h>

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

      std::cout << "There are " << sphereSource->GetOutput()->GetNumberOfPoints() << " points." << std::endl;
      std::cout << "There are " << sphereSource->GetOutput()->GetNumberOfCells() << " cells." << std::endl;

      vtkSmartPointer<vtkIdFilter> idFilter =
        vtkSmartPointer<vtkIdFilter>::New();
      idFilter->SetInputConnection(sphereSource->GetOutputPort());
      idFilter->SetIdsArrayName("ids");
      idFilter->Update();

      std::cout << "point arrays: " << std::endl;
      for(vtkIdType i = 0; i < idFilter->GetOutput()->GetPointData()->GetNumberOfArrays(); i++)
      {
        std::cout << idFilter->GetOutput()->GetPointData()->GetArrayName(i) << std::endl;
      }

      std::cout << "cell arrays: " << std::endl;
      for(vtkIdType i = 0; i < idFilter->GetOutput()->GetCellData()->GetNumberOfArrays(); i++)
      {
        std::cout << idFilter->GetOutput()->GetCellData()->GetArrayName(i) << std::endl;
      }

      vtkIdTypeArray* pointIds = vtkIdTypeArray::SafeDownCast(idFilter->GetOutput()->GetPointData()->GetArray("ids"));
      std::cout << "There are " << pointIds->GetNumberOfTuples() << " point ids" << std::endl;

      vtkIdTypeArray* cellIds = vtkIdTypeArray::SafeDownCast(idFilter->GetOutput()->GetCellData()->GetArray("ids"));
      std::cout << "There are " << cellIds->GetNumberOfTuples() << " point ids" << std::endl;

      return EXIT_SUCCESS;

    }

### CMakeLists.txt

    cmake_minimum_required(VERSION 2.8)

    PROJECT(PointCellIds)

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

    add_executable(PointCellIds MACOSX_BUNDLE PointCellIds.cxx )

    target_link_libraries(PointCellIds ${VTK_LIBRARIES})

### Download and Build PointCellIds

Click here to download PointCellIds and its CMakeLists.txt file. Once the tarball PointCellIds.tar has been downloaded and extracted,

    cd PointCellIds/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:

    ./PointCellIds

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.