# TexturedButtonWidget

VTKExamples/Cxx/Widgets/TexturedButtonWidget

### Description

This example creates a textured 2D button. The button is placed in the upper right of the display.

### Code

TexturedButtonWidget.cxx

    #include <vtkSmartPointer.h>

    #include <vtkPolyDataMapper.h>
    #include <vtkActor.h>
    #include <vtkRenderWindow.h>
    #include <vtkRenderer.h>
    #include <vtkRenderWindowInteractor.h>
    #include <vtkPolyData.h>
    #include <vtkImageData.h>

    #include <vtkCoordinate.h>
    #include <vtkSphereSource.h>
    #include <vtkButtonWidget.h>
    #include <vtkTexturedButtonRepresentation2D.h>

    static void CreateImage(vtkSmartPointer<vtkImageData> image,
                            unsigned char *color1,
                            unsigned char *color2);

    int main(int, char *[])
    {
      // Create two images for texture
      vtkSmartPointer<vtkImageData> image1 =
        vtkSmartPointer<vtkImageData>::New();
      vtkSmartPointer<vtkImageData> image2 =
        vtkSmartPointer<vtkImageData>::New();
      unsigned char banana[3] = { 227, 207, 87 };
      unsigned char tomato[3] = { 255, 99, 71 };
      CreateImage(image1, banana, tomato);
      CreateImage(image2, tomato, banana);

      // Create some geometry
      vtkSmartPointer<vtkSphereSource> sphereSource =
        vtkSmartPointer<vtkSphereSource>::New();
      sphereSource->Update();

      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);

      // Create the widget and its representation
      vtkSmartPointer<vtkTexturedButtonRepresentation2D> buttonRepresentation =
        vtkSmartPointer<vtkTexturedButtonRepresentation2D>::New();
      buttonRepresentation->SetNumberOfStates(2);
      buttonRepresentation->SetButtonTexture(0, image1);
      buttonRepresentation->SetButtonTexture(1, image2);

      vtkSmartPointer<vtkButtonWidget> buttonWidget =
        vtkSmartPointer<vtkButtonWidget>::New();
      buttonWidget->SetInteractor(renderWindowInteractor);
      buttonWidget->SetRepresentation(buttonRepresentation);

      // Add the actors to the scene
      renderer->AddActor(actor);
      renderer->SetBackground(.1, .2, .5);

      renderWindow->SetSize(640, 480);
      renderWindow->Render();

      // Place the widget. Must be done after a render so that the
      // viewport is defined.
      // Here the widget placement is in normalized display coordinates
      vtkSmartPointer<vtkCoordinate> upperRight =
        vtkSmartPointer<vtkCoordinate>::New();
      upperRight->SetCoordinateSystemToNormalizedDisplay();
      upperRight->SetValue(1.0, 1.0);

      double bds[6];
      double sz = 50.0;
      bds[0] = upperRight->GetComputedDisplayValue(renderer)[0] - sz;
      bds[1] = bds[0] + sz;
      bds[2] = upperRight->GetComputedDisplayValue(renderer)[1] - sz;
      bds[3] = bds[2] + sz;
      bds[4] = bds[5] = 0.0;

      // Scale to 1, default is .5
      buttonRepresentation->SetPlaceFactor(1);
      buttonRepresentation->PlaceWidget(bds);

      buttonWidget->On();

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

      return EXIT_SUCCESS;
    }

    void CreateImage(vtkSmartPointer<vtkImageData> image,
                     unsigned char* color1,
                     unsigned char* color2)
    {
      // Specify the size of the image data
      image->SetDimensions(10, 10, 1);
      image->AllocateScalars(VTK_UNSIGNED_CHAR, 3);

      int* dims = image->GetDimensions();

      // Fill the image with
      for (int y = 0; y < dims[1]; y++)
      {
        for (int x = 0; x < dims[0]; x++)
        {
          unsigned char* pixel =
            static_cast<unsigned char*>(image->GetScalarPointer(x, y, 0));
          if (x < 5)
          {
            pixel[0] = color1[0];
            pixel[1] = color1[1];
            pixel[2] = color1[2];
          }
          else
          {
            pixel[0] = color2[0];
            pixel[1] = color2[1];
            pixel[2] = color2[2];
          }
        }
      }
    }

### CMakeLists.txt

    cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

    project(TexturedButtonWidget)

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

### Download and Build TexturedButtonWidget

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

    cd TexturedButtonWidget/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:

    ./TexturedButtonWidget

WINDOWS USERS

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