# LoopShrink

VTKExamples/Cxx/Visualization/LoopShrink

### Code

LoopShrink.cxx

    #include <vtkRenderer.h>
    #include <vtkRenderWindow.h>
    #include <vtkRenderWindowInteractor.h>
    #include <vtkSphereSource.h>
    #include <vtkShrinkFilter.h>
    #include <vtkElevationFilter.h>
    #include <vtkDataSetMapper.h>
    #include <vtkActor.h>
    #include <vtkCullerCollection.h>
    int main( int argc, char *argv[] )
    {
      vtkSmartPointer<vtkRenderer> renderer =
        vtkSmartPointer<vtkRenderer>::New();
      renderer->GetCullers()->RemoveAllItems();

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

      vtkSmartPointer<vtkSphereSource> sphere =
        vtkSmartPointer<vtkSphereSource>::New();
      sphere->SetThetaResolution(12); sphere->SetPhiResolution(12);

      vtkSmartPointer<vtkShrinkFilter> shrink =
        vtkSmartPointer<vtkShrinkFilter>::New();
      shrink->SetInputConnection(sphere->GetOutputPort());
      shrink->SetShrinkFactor(0.9);

      vtkSmartPointer<vtkElevationFilter> colorIt =
        vtkSmartPointer<vtkElevationFilter>::New();
      colorIt->SetInputConnection(shrink->GetOutputPort());
      colorIt->SetLowPoint(0,0,-.5);
      colorIt->SetHighPoint(0,0,.5);

      vtkSmartPointer<vtkDataSetMapper> mapper =
        vtkSmartPointer<vtkDataSetMapper>::New();
      mapper->SetInputConnection(colorIt->GetOutputPort());

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

      renderer->AddActor(actor);
      renderer->SetBackground(1,1,1);
      renWin->SetSize(640, 480);

      renWin->Render();

      // interact with data
      iren->Start();

      return EXIT_SUCCESS;
    }

### CMakeLists.txt

    cmake_minimum_required(VERSION 2.8)

    PROJECT(LoopShrink)

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

    add_executable(LoopShrink MACOSX_BUNDLE LoopShrink.cxx )

    target_link_libraries(LoopShrink ${VTK_LIBRARIES})

### Download and Build LoopShrink

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

    cd LoopShrink/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:

    ./LoopShrink

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.