# DistanceWidget

VTKExamples/Cxx/Widgets/DistanceWidget

### Description

- Contributed by Arnaud Gelas

Click two points to see the distance between them.

### Code

DistanceWidget.cxx

    #include <vtkRenderWindow.h>
    #include <vtkRenderer.h>
    #include <vtkRenderWindowInteractor.h>
    #include <vtkSmartPointer.h>
    #include <vtkDistanceWidget.h>
    #include <vtkDistanceRepresentation.h>

    int main(int, char *[])
    {
      // 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);

      vtkSmartPointer<vtkDistanceWidget> distanceWidget =
        vtkSmartPointer<vtkDistanceWidget>::New();
      distanceWidget->SetInteractor(renderWindowInteractor);
      distanceWidget->CreateDefaultRepresentation();
      static_cast<vtkDistanceRepresentation *>(distanceWidget->GetRepresentation())
        ->SetLabelFormat("%-#6.3g mm");

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

      renderWindowInteractor->Initialize();
      renderWindow->Render();
      distanceWidget->On();

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

      return EXIT_SUCCESS;
    }

### CMakeLists.txt

    cmake_minimum_required(VERSION 2.8)

    PROJECT(DistanceWidget)

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

    add_executable(DistanceWidget MACOSX_BUNDLE DistanceWidget.cxx)

    target_link_libraries(DistanceWidget ${VTK_LIBRARIES})

### Download and Build DistanceWidget

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

    cd DistanceWidget/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:

    ./DistanceWidget

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.