# VisualizeVTP

VTKExamples/Cxx/Visualization/VisualizeVTP

### Description

This example shows how to load a vtp file and render it in an interactive window. The example accepts a .vtp file on the command line.

### Code

VisualizeVTP.cxx

    #include <vtkSmartPointer.h>

    #include <vtkActor.h>
    #include <vtkPolyDataMapper.h>
    #include <vtkRenderWindow.h>
    #include <vtkRenderWindowInteractor.h>
    #include <vtkRenderer.h>
    #include <vtkXMLPolyDataReader.h>

    int main (int argc, char *argv[])
    {
      if (argc < 2)
      {
        std::cerr << "Usage: " << argv[0]
                  << " Filename(.vtp)"
                  << std::endl;
        return (EXIT_FAILURE);
      }

      vtkSmartPointer<vtkXMLPolyDataReader> reader =
        vtkSmartPointer<vtkXMLPolyDataReader>::New();
      reader->SetFileName(argv[1]);

      // Create a mapper
      vtkSmartPointer<vtkPolyDataMapper> mapper =
        vtkSmartPointer<vtkPolyDataMapper>::New();
      mapper->SetInputConnection(reader->GetOutputPort());

      // Create an actor
      vtkSmartPointer<vtkActor> actor =
        vtkSmartPointer<vtkActor>::New();
      actor->SetMapper(mapper);

      // A renderer and render window
      vtkSmartPointer<vtkRenderer> renderer =
        vtkSmartPointer<vtkRenderer>::New();
      vtkSmartPointer<vtkRenderWindow> renderWindow =
        vtkSmartPointer<vtkRenderWindow>::New();
      renderWindow->AddRenderer(renderer);

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

      // Add the actors to the scene
      renderer->AddActor(actor);
      renderer->SetBackground(.3, .4, .5);

      // Render an image (lights and cameras are created automatically)
      renderWindow->Render();

      // Begin mouse interaction
      renderWindowInteractor->Start();

      return EXIT_SUCCESS;
    }

### CMakeLists.txt

    cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

    project(VisualizeVTP)

    find_package(VTK COMPONENTS
      vtkCommonCore
      vtkIOXML
      vtkInteractionStyle
      vtkRenderingCore
      vtkRenderingFreeType
      vtkRenderingOpenGL2 QUIET)
    if (NOT VTK_FOUND)
      message("Skipping VisualizeVTP: ${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(VisualizeVTP MACOSX_BUNDLE VisualizeVTP.cxx )
      target_link_libraries(VisualizeVTP PRIVATE ${VTK_LIBRARIES})
    else ()
      # include all components
      add_executable(VisualizeVTP MACOSX_BUNDLE VisualizeVTP.cxx )
      target_link_libraries(VisualizeVTP PRIVATE ${VTK_LIBRARIES})
      # vtk_module_autoinit is needed
      vtk_module_autoinit(
        TARGETS VisualizeVTP
        MODULES ${VTK_LIBRARIES}
        )
    endif ()

### Download and Build VisualizeVTP

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

    cd VisualizeVTP/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:

    ./VisualizeVTP

WINDOWS USERS

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