# StyleSwitch

VTKExamples/Cxx/Interaction/StyleSwitch

### Description

The class vtkInteractorStyleSwitch allows handles interactively switching between four interactor styles -- joystick actor, joystick camera, trackball actor, and trackball camera. Type 'j' or 't' to select joystick or trackball, and type 'c' or 'a' to select camera or actor. The default interactor style is joystick camera.

### Code

StyleSwitch.cxx

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

    int main (int, char *[])
    {

      vtkSmartPointer<vtkSphereSource> sphereSource =
        vtkSmartPointer<vtkSphereSource>::New();

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

      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(1,1,1); // Background color white

      // Render
      renderWindow->Render();

      vtkSmartPointer<vtkInteractorStyleSwitch> style =
          vtkSmartPointer<vtkInteractorStyleSwitch>::New();

      renderWindowInteractor->SetInteractorStyle( style );

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

      return EXIT_SUCCESS;
    }

### CMakeLists.txt

    cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

    project(StyleSwitch)

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

### Download and Build StyleSwitch

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

    cd StyleSwitch/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:

    ./StyleSwitch

WINDOWS USERS

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