# FrameRate

VTKExamples/Cxx/Utilities/FrameRate

### Code

FrameRate.cxx

    #include <vtkSmartPointer.h>
    #include <vtkCallbackCommand.h>
    #include <vtkRenderer.h>
    #include <vtkRenderWindowInteractor.h>
    #include <vtkMath.h>
    #include <vtkRenderWindow.h>
    #include <vtkTimerLog.h>
    #include <vtkSphereSource.h>
    #include <vtkPolyDataMapper.h>
    #include <vtkActor.h>

    static void CallbackFunction ( vtkObject* caller, long unsigned int eventId,
              void* clientData, void* callData );

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

      for(unsigned int i = 0; i < 10; i++)
      {
        // Create a sphere
        vtkSmartPointer<vtkSphereSource> sphereSource =
          vtkSmartPointer<vtkSphereSource>::New();
        sphereSource->SetCenter(i, 0, 0);

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

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

        renderer->AddActor(actor);
      }

      vtkSmartPointer<vtkRenderWindow> renderWindow =
        vtkSmartPointer<vtkRenderWindow>::New();
      renderWindow->AddRenderer(renderer);

      vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
        vtkSmartPointer<vtkRenderWindowInteractor>::New();
      renderWindowInteractor->SetRenderWindow(renderWindow);

      vtkSmartPointer<vtkCallbackCommand> callback =
        vtkSmartPointer<vtkCallbackCommand>::New();

      callback->SetCallback(CallbackFunction);
      renderer->AddObserver(vtkCommand::EndEvent, callback);

      renderer->SetBackground(.3, .6, .3); // Background color green

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

    void CallbackFunction(vtkObject* caller, long unsigned int vtkNotUsed(eventId), void* vtkNotUsed(clientData), void* vtkNotUsed(callData) )
    {
      vtkRenderer* renderer = static_cast<vtkRenderer*>(caller);

      double timeInSeconds = renderer->GetLastRenderTimeInSeconds();
      double fps = 1.0/timeInSeconds;
      std::cout << "FPS: " << fps << std::endl;

      std::cout << "Callback" << std::endl;
    }

### CMakeLists.txt

    cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

    project(FrameRate)

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

### Download and Build FrameRate

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

    cd FrameRate/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:

    ./FrameRate

WINDOWS USERS

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