# ReadRectilinearGrid

VTKExamples/Cxx/IO/ReadRectilinearGrid

### Description

This example reads a rectilinear grid (.vtr) file. An example file can be found at VTKData/Data/cth.vtr

### Code

ReadRectilinearGrid.cxx

    #include <vtkSmartPointer.h>
    #include <vtkProperty.h>
    #include <vtkDataSetMapper.h>
    #include <vtkXMLRectilinearGridReader.h>
    #include <vtkRectilinearGridGeometryFilter.h>
    #include <vtkRenderWindow.h>
    #include <vtkRenderWindowInteractor.h>
    #include <vtkRenderer.h>

    int main(int argc, char* argv[])
    {
      // Verify input arguments
      if(argc < 2)
      {
        std::cout << "Usage: " << argv[0]
                  << " Filename.vtr" << std::endl;
        return EXIT_FAILURE;
      }

      // Parse arguments
      std::string inputFilename = argv[1];

      // Read the file
      vtkSmartPointer<vtkXMLRectilinearGridReader> reader =
        vtkSmartPointer<vtkXMLRectilinearGridReader>::New();
      reader->SetFileName(inputFilename.c_str());
      reader->Update();
    /*
      vtkSmartPointer<vtkRectilinearGridGeometryFilter> geometryFilter =
        vtkSmartPointer<vtkRectilinearGridGeometryFilter>::New();
      geometryFilter->SetInputConnection(reader->GetOutputPort());
      geometryFilter->Update();
    */
      // Visualize
      vtkSmartPointer<vtkDataSetMapper> mapper =
        vtkSmartPointer<vtkDataSetMapper>::New();
      //mapper->SetInputConnection(geometryFilter->GetOutputPort());
      mapper->SetInputConnection(reader->GetOutputPort());

      vtkSmartPointer<vtkActor> actor =
        vtkSmartPointer<vtkActor>::New();
      actor->SetMapper(mapper);
      actor->GetProperty()->SetRepresentationToWireframe();

      vtkSmartPointer<vtkRenderer> renderer =
        vtkSmartPointer<vtkRenderer>::New();
      vtkSmartPointer<vtkRenderWindow> renderWindow =
        vtkSmartPointer<vtkRenderWindow>::New();
      renderWindow->AddRenderer(renderer);
      vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
        vtkSmartPointer<vtkRenderWindowInteractor>::New();
      renderWindowInteractor->SetRenderWindow(renderWindow);

      renderer->AddActor(actor);
      renderer->SetBackground(.3, .6, .3); // Background color green

      renderWindow->Render();
      renderWindowInteractor->Start();

      return EXIT_SUCCESS;
    }

### CMakeLists.txt

    cmake_minimum_required(VERSION 2.8)

    PROJECT(ReadRectilinearGrid)

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

    add_executable(ReadRectilinearGrid MACOSX_BUNDLE ReadRectilinearGrid.cxx)

    target_link_libraries(ReadRectilinearGrid ${VTK_LIBRARIES})

### Download and Build ReadRectilinearGrid

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

    cd ReadRectilinearGrid/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:

    ./ReadRectilinearGrid

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.