# DijkstraGraphGeodesicPath

VTKExamples/Cxx/PolyData/DijkstraGraphGeodesicPath

Other Languages

See (CSharp)

### Code

DijkstraGraphGeodesicPath.cxx

    #include <vtkSphereSource.h>
    #include <vtkProperty.h>
    #include <vtkPolyData.h>
    #include <vtkSmartPointer.h>
    #include <vtkPolyDataMapper.h>
    #include <vtkActor.h>
    #include <vtkRenderWindow.h>
    #include <vtkRenderer.h>
    #include <vtkRenderWindowInteractor.h>
    #include <vtkDijkstraGraphGeodesicPath.h>

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

      vtkSmartPointer<vtkDijkstraGraphGeodesicPath> dijkstra =
        vtkSmartPointer<vtkDijkstraGraphGeodesicPath>::New();
      dijkstra->SetInputConnection(sphereSource->GetOutputPort());
      dijkstra->SetStartVertex(0);
      dijkstra->SetEndVertex(10);
      dijkstra->Update();

      // Create a mapper and actor
      vtkSmartPointer<vtkPolyDataMapper> pathMapper =
        vtkSmartPointer<vtkPolyDataMapper>::New();
      pathMapper->SetInputConnection(dijkstra->GetOutputPort());

      vtkSmartPointer<vtkActor> pathActor =
        vtkSmartPointer<vtkActor>::New();
      pathActor->SetMapper(pathMapper);
      pathActor->GetProperty()->SetColor(1,0,0); // Red
      pathActor->GetProperty()->SetLineWidth(4);

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

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

      //Create a renderer, render window, and interactor
      vtkSmartPointer<vtkRenderer> renderer =
        vtkSmartPointer<vtkRenderer>::New();
      vtkSmartPointer<vtkRenderWindow> renderWindow =
        vtkSmartPointer<vtkRenderWindow>::New();
      renderWindow->AddRenderer(renderer);
      vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
        vtkSmartPointer<vtkRenderWindowInteractor>::New();
      renderWindowInteractor->SetRenderWindow(renderWindow);

      //Add the actor to the scene
      renderer->AddActor(actor);
      renderer->AddActor(pathActor);
      renderer->SetBackground(.3, .6, .3); // Background color green

      //Render and interact
      renderWindow->Render();
      renderWindowInteractor->Start();

      return EXIT_SUCCESS;
    }

### CMakeLists.txt

    cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

    project(DijkstraGraphGeodesicPath)

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

### Download and Build DijkstraGraphGeodesicPath

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

    cd DijkstraGraphGeodesicPath/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:

    ./DijkstraGraphGeodesicPath

WINDOWS USERS

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