# BalloonWidget

VTKExamples/Cxx/Widgets/BalloonWidget

### Description

This example creates a sphere and a regular polygon. The balloon text describes each object when you hover over it.

Note

This original source code for this example is here.

### Code

BalloonWidget.cxx

    #include <vtkActor.h>
    #include <vtkBalloonRepresentation.h>
    #include <vtkBalloonWidget.h>
    #include <vtkCommand.h>
    #include <vtkInteractorStyleTrackball.h>
    #include <vtkInteractorStyleTrackballCamera.h>
    #include <vtkPolyData.h>
    #include <vtkPolyDataMapper.h>
    #include <vtkRenderWindow.h>
    #include <vtkRenderWindowInteractor.h>
    #include <vtkRenderer.h>
    #include <vtkSmartPointer.h>
    #include <vtkSphereSource.h>
    #include <vtkRegularPolygonSource.h>

    int main (int, char *[])
    {
      // Sphere
      vtkSmartPointer<vtkSphereSource> sphereSource =
        vtkSmartPointer<vtkSphereSource>::New();
      sphereSource->SetCenter(-4.0, 0.0, 0.0);
      sphereSource->SetRadius(4.0);
      sphereSource->Update();

      vtkSmartPointer<vtkPolyDataMapper> sphereMapper =
        vtkSmartPointer<vtkPolyDataMapper>::New();
      sphereMapper->SetInputConnection(sphereSource->GetOutputPort());

      vtkSmartPointer<vtkActor> sphereActor =
        vtkSmartPointer<vtkActor>::New();
      sphereActor->SetMapper(sphereMapper);

      // Regular Polygon
      vtkSmartPointer<vtkRegularPolygonSource> regularPolygonSource =
        vtkSmartPointer<vtkRegularPolygonSource>::New();
      regularPolygonSource->SetCenter(4.0, 0.0, 0.0);
      regularPolygonSource->SetRadius(4.0);
      regularPolygonSource->Update();

      vtkSmartPointer<vtkPolyDataMapper> regularPolygonMapper =
        vtkSmartPointer<vtkPolyDataMapper>::New();
      regularPolygonMapper->SetInputConnection(regularPolygonSource->GetOutputPort());

      vtkSmartPointer<vtkActor> regularPolygonActor =
        vtkSmartPointer<vtkActor>::New();
      regularPolygonActor->SetMapper(regularPolygonMapper);

      // 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);

      // Create the widget
      vtkSmartPointer<vtkBalloonRepresentation> balloonRep =
        vtkSmartPointer<vtkBalloonRepresentation>::New();
      balloonRep->SetBalloonLayoutToImageRight();

      vtkSmartPointer<vtkBalloonWidget> balloonWidget =
        vtkSmartPointer<vtkBalloonWidget>::New();
      balloonWidget->SetInteractor(renderWindowInteractor);
      balloonWidget->SetRepresentation(balloonRep);
      balloonWidget->AddBalloon(sphereActor,
                                "This is a sphere",NULL);
      balloonWidget->AddBalloon(regularPolygonActor,
                                "This is a regular polygon",NULL);

      // Add the actors to the scene
      renderer->AddActor(sphereActor);
      renderer->AddActor(regularPolygonActor);

      // Render
      renderWindow->Render();
      balloonWidget->EnabledOn();

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

      return EXIT_SUCCESS;
    }

### CMakeLists.txt

    cmake_minimum_required(VERSION 2.8)

    PROJECT(BalloonWidget)

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

    add_executable(BalloonWidget MACOSX_BUNDLE BalloonWidget.cxx )

    target_link_libraries(BalloonWidget ${VTK_LIBRARIES})

### Download and Build BalloonWidget

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

    cd BalloonWidget/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:

    ./BalloonWidget

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.