# MutableGraphHelper

VTKExamples/Cxx/InfoVis/MutableGraphHelper

### Code

MutableGraphHelper.cxx

    #include <vtkSmartPointer.h>
    #include <vtkMutableDirectedGraph.h>
    #include <vtkMutableUndirectedGraph.h>
    #include <vtkMutableGraphHelper.h>
    #include <vtkGraphLayoutView.h>
    #include <vtkRenderWindowInteractor.h>

    int main(int, char*[])
    {
      vtkSmartPointer<vtkMutableUndirectedGraph> g =
        vtkSmartPointer<vtkMutableUndirectedGraph>::New();

      vtkSmartPointer<vtkMutableGraphHelper> graphHelper =
        vtkSmartPointer<vtkMutableGraphHelper>::New();
      graphHelper->SetGraph(g);
      vtkIdType v0 = graphHelper->AddVertex();
      vtkIdType v1 = graphHelper->AddVertex();

      graphHelper->AddEdge(v0, v1);

      // Can also do this:
      graphHelper->RemoveEdge(0);

      vtkSmartPointer<vtkGraphLayoutView> treeLayoutView =
        vtkSmartPointer<vtkGraphLayoutView>::New();
      treeLayoutView->AddRepresentationFromInput(graphHelper->GetGraph());
      treeLayoutView->SetLayoutStrategyToTree();
      treeLayoutView->ResetCamera();
      treeLayoutView->Render();
      treeLayoutView->GetInteractor()->Start();

      return EXIT_SUCCESS;
    }

### CMakeLists.txt

    cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

    project(MutableGraphHelper)

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

### Download and Build MutableGraphHelper

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

    cd MutableGraphHelper/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:

    ./MutableGraphHelper

WINDOWS USERS

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