# ImageStack

VTKExamples/Cxx/Images/ImageStack

### Code

ImageStack.cxx

    #include <vtkVersion.h>
    #include <vtkImageData.h>
    #include <vtkImageMapper.h>
    #include <vtkImageProperty.h>
    #include <vtkImageSliceMapper.h>
    #include <vtkImageSlice.h>
    #include <vtkImageStack.h>
    #include <vtkInteractorStyleImage.h>
    #include <vtkRenderer.h>
    #include <vtkRenderWindow.h>
    #include <vtkRenderWindowInteractor.h>
    #include <vtkSmartPointer.h>

    static void CreateColorImage(vtkImageData*, const int corner, const unsigned int channel);

    int main(int, char *[])
    {
      // Image 1
      vtkSmartPointer<vtkImageData> image1 = vtkSmartPointer<vtkImageData>::New();
      CreateColorImage(image1, 1, 0);

      vtkSmartPointer<vtkImageSliceMapper> imageSliceMapper1 = vtkSmartPointer<vtkImageSliceMapper>::New();
    #if VTK_MAJOR_VERSION <= 5
      imageSliceMapper1->SetInputConnection(image1->GetProducerPort());
    #else
      imageSliceMapper1->SetInputData(image1);
    #endif

      vtkSmartPointer<vtkImageSlice> imageSlice1 = vtkSmartPointer<vtkImageSlice>::New();
      imageSlice1->SetMapper(imageSliceMapper1);
      imageSlice1->GetProperty()->SetOpacity(.5);

      // Image 2
      vtkSmartPointer<vtkImageData> image2 = vtkSmartPointer<vtkImageData>::New();
      CreateColorImage(image2, 4, 1);

      vtkSmartPointer<vtkImageSliceMapper> imageSliceMapper2 = vtkSmartPointer<vtkImageSliceMapper>::New();
    #if VTK_MAJOR_VERSION <= 5
      imageSliceMapper2->SetInputConnection(image2->GetProducerPort());
    #else
      imageSliceMapper2->SetInputData(image2);
    #endif

      vtkSmartPointer<vtkImageSlice> imageSlice2 = vtkSmartPointer<vtkImageSlice>::New();
      imageSlice2->SetMapper(imageSliceMapper2);
      imageSlice2->GetProperty()->SetOpacity(.5);

      // Stack
      vtkSmartPointer<vtkImageStack> imageStack = vtkSmartPointer<vtkImageStack>::New();
      imageStack->AddImage(imageSlice1);
      imageStack->AddImage(imageSlice2);
      //imageStack->SetActiveLayer(1);

      // Setup renderers
      vtkSmartPointer<vtkRenderer> renderer = vtkSmartPointer<vtkRenderer>::New();
      renderer->AddViewProp(imageStack);
      renderer->ResetCamera();

      // Setup render window
      vtkSmartPointer<vtkRenderWindow> renderWindow = vtkSmartPointer<vtkRenderWindow>::New();
      renderWindow->AddRenderer(renderer);

      // Setup render window interactor
      vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
        vtkSmartPointer<vtkRenderWindowInteractor>::New();

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

      renderWindowInteractor->SetInteractorStyle(style);

      // Render and start interaction
      renderWindowInteractor->SetRenderWindow(renderWindow);
      renderWindowInteractor->Initialize();

      renderWindowInteractor->Start();

      return EXIT_SUCCESS;
    }

    void CreateColorImage(vtkImageData* image, const int corner, const unsigned int channel)
    {
      image->SetDimensions(10, 10, 1);

    #if VTK_MAJOR_VERSION <= 5
      image->SetNumberOfScalarComponents(3);
      image->SetScalarTypeToUnsignedChar();
      image->AllocateScalars();
    #else
      image->AllocateScalars(VTK_UNSIGNED_CHAR,3);
    #endif
      for(unsigned int x = 0; x < 10; x++)
      {
        for(unsigned int y = 0; y < 10; y++)
        {
          unsigned char* pixel = static_cast<unsigned char*>(image->GetScalarPointer(x,y,0));
          pixel[0] = 0;
          pixel[1] = 0;
          pixel[2] = 0;
        }
      }

      for(int x = corner; x < corner+3; x++)
      {
        for(int y = corner; y < corner+3; y++)
        {
          unsigned char* pixel = static_cast<unsigned char*>(image->GetScalarPointer(x,y,0));
          pixel[channel] = 255;
        }
      }
    }

### CMakeLists.txt

    cmake_minimum_required(VERSION 2.8)

    PROJECT(ImageStack)

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

    add_executable(ImageStack MACOSX_BUNDLE ImageStack.cxx )

    target_link_libraries(ImageStack ${VTK_LIBRARIES})

### Download and Build ImageStack

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

    cd ImageStack/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:

    ./ImageStack

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.