# GenericDataObjectReader

VTKExamples/Cxx/IO/GenericDataObjectReader

### Code

GenericDataObjectReader.cxx

    #include <vtkGenericDataObjectReader.h>
    #include <vtkStructuredGrid.h>
    #include <vtkSmartPointer.h>
    #include <vtkPolyData.h>
    #include <string>

    int main ( int argc, char *argv[] )
    {
      // Ensure a filename was specified
      if(argc != 2)
      {
        std::cerr << "Usage: " << argv[0] << " InputFilename" << endl;
        return EXIT_FAILURE;
      }

      // Get the filename from the command line
      std::string inputFilename = argv[1];

      // Get all data from the file
      vtkSmartPointer<vtkGenericDataObjectReader> reader =
          vtkSmartPointer<vtkGenericDataObjectReader>::New();
      reader->SetFileName(inputFilename.c_str());
      reader->Update();

      // All of the standard data types can be checked and obtained like this:
      if(reader->IsFilePolyData())
      {
        std::cout << "output is a polydata" << std::endl;
        vtkPolyData* output = reader->GetPolyDataOutput();
        std::cout << "output has " << output->GetNumberOfPoints() << " points." << std::endl;
      }

      return EXIT_SUCCESS;
    }

### CMakeLists.txt

    cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

    project(GenericDataObjectReader)

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

### Download and Build GenericDataObjectReader

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

    cd GenericDataObjectReader/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:

    ./GenericDataObjectReader

WINDOWS USERS

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