# PlateVibration

VTKExamples/Cxx/VisualizationAlgorithms/PlateVibration

### Description

The motion of a vibrating beam is shown. The original undeformed outline is shown as a wireframe.

### Code

PlateVibration.cxx

    // Translated from vib.tcl

    #include <vtkActor.h>
    #include <vtkCallbackCommand.h>
    #include <vtkCamera.h>
    #include <vtkDataSetMapper.h>
    #include <vtkLookupTable.h>
    #include <vtkNamedColors.h>
    #include <vtkOutlineFilter.h>
    #include <vtkPolyData.h>
    #include <vtkPolyDataMapper.h>
    #include <vtkPolyDataNormals.h>
    #include <vtkPolyDataReader.h>
    #include <vtkProp3D.h>
    #include <vtkProperty.h>
    #include <vtkRenderWindow.h>
    #include <vtkRenderWindowInteractor.h>
    #include <vtkRenderer.h>
    #include <vtkSmartPointer.h>
    #include <vtkVectorDot.h>
    #include <vtkWarpVector.h>

    #include <algorithm>
    #include <string>
    #include <vector>

    int main(int argc, char* argv[])
    {
      auto Scale = [](std::vector<double>& v, double scale) {
        std::transform(std::begin(v), std::end(v), std::begin(v),
                       [=](double const& n) { return n / scale; });
        return;
      };

      if (argc < 2)
      {
        std::cout << "Usage: " << argv[0] << " filename" << std::endl;
        std::cout << "where: filename is the file plate.vtk." << std::endl;
        std::cout
          << "Produces figure 6-14(a) Beam displacement from the VTK Textbook."
          << std::endl;
        return EXIT_FAILURE;
      }

      std::string fileName = argv[1];

      vtkSmartPointer<vtkNamedColors> colors =
        vtkSmartPointer<vtkNamedColors>::New();
      // Set the background color and plate color. Match those in VTKTextbook.pdf.
      auto scale = 256.0;
      std::vector<double> bkg = {65, 99, 149};
      Scale(bkg, scale);
      std::vector<double> bar = {255, 160, 140};
      Scale(bar, scale);
      colors->SetColor("BkgColor", bkg[0], bkg[1], bkg[2]);
      colors->SetColor("PlateColor", bar[0], bar[1], bar[2]);

      // Read a vtk file
      //
      vtkSmartPointer<vtkPolyDataReader> plate =
        vtkSmartPointer<vtkPolyDataReader>::New();
      plate->SetFileName(fileName.c_str());
      plate->Update();
      double bounds[6];
      plate->GetOutput()->GetBounds(bounds);
      plate->SetVectorsName("mode2");

      vtkSmartPointer<vtkPolyDataNormals> normals =
        vtkSmartPointer<vtkPolyDataNormals>::New();
      normals->SetInputConnection(plate->GetOutputPort());
      vtkSmartPointer<vtkWarpVector> warp = vtkSmartPointer<vtkWarpVector>::New();
      warp->SetInputConnection(normals->GetOutputPort());
      warp->SetScaleFactor(0.5);
      vtkSmartPointer<vtkVectorDot> color = vtkSmartPointer<vtkVectorDot>::New();
      color->SetInputConnection(warp->GetOutputPort());
      vtkSmartPointer<vtkDataSetMapper> plateMapper =
        vtkSmartPointer<vtkDataSetMapper>::New();
      plateMapper->SetInputConnection(warp->GetOutputPort());
      vtkSmartPointer<vtkActor> plateActor = vtkSmartPointer<vtkActor>::New();
      plateActor->SetMapper(plateMapper);
      plateActor->GetProperty()->SetColor(
        colors->GetColor3d("PlateColor").GetData());
      plateActor->RotateX(-90);

      // Create the outline.
      //
      vtkSmartPointer<vtkOutlineFilter> outline =
        vtkSmartPointer<vtkOutlineFilter>::New();
      outline->SetInputConnection(plate->GetOutputPort());
      vtkSmartPointer<vtkPolyDataMapper> spikeMapper =
        vtkSmartPointer<vtkPolyDataMapper>::New();
      spikeMapper->SetInputConnection(outline->GetOutputPort());
      vtkSmartPointer<vtkActor> outlineActor = vtkSmartPointer<vtkActor>::New();
      outlineActor->SetMapper(spikeMapper);
      outlineActor->RotateX(-90);
      outlineActor->GetProperty()->SetColor(colors->GetColor3d("White").GetData());

      // Create the RenderWindow, Renderer and both Actors
      //
      vtkSmartPointer<vtkRenderer> ren = vtkSmartPointer<vtkRenderer>::New();
      vtkSmartPointer<vtkRenderWindow> renWin =
        vtkSmartPointer<vtkRenderWindow>::New();
      renWin->AddRenderer(ren);

      vtkSmartPointer<vtkRenderWindowInteractor> iren =
        vtkSmartPointer<vtkRenderWindowInteractor>::New();
      iren->SetRenderWindow(renWin);

      // Add the actors to the renderer, set the background and size
      //
      ren->AddActor(plateActor);
      ren->AddActor(outlineActor);
      renWin->SetSize(500, 500);

      // Render the image.
      renWin->Render();
      ren->SetBackground(colors->GetColor3d("BkgColor").GetData());
      // This closely matches the original illustration.
      ren->GetActiveCamera()->SetPosition(-3.7, 13, 15.5);
      ren->ResetCameraClippingRange();

      iren->Start();

      return EXIT_SUCCESS;
    }

### CMakeLists.txt

    cmake_minimum_required(VERSION 2.8)

    PROJECT(PlateVibration)

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

    add_executable(PlateVibration MACOSX_BUNDLE PlateVibration.cxx )

    target_link_libraries(PlateVibration ${VTK_LIBRARIES})

### Download and Build PlateVibration

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

    cd PlateVibration/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:

    ./PlateVibration

WINDOWS USERS

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