# ComplexV

VTKExamples/Cxx/Visualization/ComplexV

### Description

ComplexV from the VTK Textbook. The original example was written in TCL.

The example shows 167,000 3D vectors (using oriented and scaled lines) in the region of the human carotid artery. The larger vectors lie inside the arteries, the smaller vectors lie outside the arteries and are randomly oriented (measurement error) but small in magnitude. Clearly the details of the vector field are not discernible from this image.

### Code

ComplexV.cxx

    #include <vtkSmartPointer.h>

    #include <vtkHedgeHog.h>
    #include <vtkOutlineFilter.h>

    #include <vtkLookupTable.h>
    #include <vtkRenderer.h>
    #include <vtkRenderWindow.h>
    #include <vtkRenderWindowInteractor.h>
    #include <vtkStructuredPointsReader.h>
    #include <vtkPolyDataMapper.h>
    #include <vtkActor.h>
    #include <vtkProperty.h>
    #include <vtkCamera.h>

    int main (int /* argc */, char *argv[])
    {
      vtkSmartPointer<vtkStructuredPointsReader> reader =
        vtkSmartPointer<vtkStructuredPointsReader>::New();
      reader->SetFileName(argv[1]);

      vtkSmartPointer<vtkHedgeHog> hhog =
        vtkSmartPointer<vtkHedgeHog>::New();
      hhog->SetInputConnection(reader->GetOutputPort());
      hhog->SetScaleFactor(0.3);

      vtkSmartPointer<vtkLookupTable> lut =
        vtkSmartPointer<vtkLookupTable>::New();
    //  lut->SetHueRange(.667, 0.0);
      lut->Build();

      vtkSmartPointer<vtkPolyDataMapper> hhogMapper =
        vtkSmartPointer<vtkPolyDataMapper>::New();
      hhogMapper->SetInputConnection(hhog->GetOutputPort());
      hhogMapper->SetScalarRange(50, 550);
      hhogMapper->SetLookupTable(lut);

      vtkSmartPointer<vtkActor> hhogActor =
        vtkSmartPointer<vtkActor>::New();
      hhogActor->SetMapper(hhogMapper);

      vtkSmartPointer<vtkOutlineFilter> outline =
        vtkSmartPointer<vtkOutlineFilter>::New();
      outline->SetInputConnection(reader->GetOutputPort());

      vtkSmartPointer<vtkPolyDataMapper> outlineMapper =
        vtkSmartPointer<vtkPolyDataMapper>::New();
      outlineMapper->SetInputConnection(outline->GetOutputPort());

      vtkSmartPointer<vtkActor> outlineActor =
        vtkSmartPointer<vtkActor>::New();
      outlineActor->SetMapper(outlineMapper);
      outlineActor->GetProperty()->SetColor(0, 0, 0);

      vtkSmartPointer<vtkRenderer> aRenderer =
        vtkSmartPointer<vtkRenderer>::New();
      vtkSmartPointer<vtkRenderWindow> aRenderWindow =
        vtkSmartPointer<vtkRenderWindow>::New();
      aRenderWindow->AddRenderer(aRenderer);
      vtkSmartPointer<vtkRenderWindowInteractor> anInteractor =
        vtkSmartPointer<vtkRenderWindowInteractor>::New();
      anInteractor->SetRenderWindow(aRenderWindow);
      aRenderWindow->SetSize(640, 480);

      aRenderer->AddActor(outlineActor);
      aRenderer->AddActor(hhogActor);

      aRenderer->SetBackground(.5, .5, .5);

      // Generate an interesting view

      aRenderer->GetActiveCamera()->SetFocalPoint(0,0,0);
      aRenderer->GetActiveCamera()->SetPosition(1,0,0);
      aRenderer->GetActiveCamera()->SetViewUp(0,0,1);
      aRenderer->ResetCamera();

      aRenderer->GetActiveCamera()->Azimuth(60);
      aRenderer->GetActiveCamera()->Elevation(30);
      aRenderer->GetActiveCamera()->Dolly(1.1);
      aRenderer->ResetCameraClippingRange();

      aRenderWindow->Render();

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

      return EXIT_SUCCESS;
    }

### CMakeLists.txt

    cmake_minimum_required(VERSION 2.8)

    PROJECT(ComplexV)

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

    add_executable(ComplexV MACOSX_BUNDLE ComplexV.cxx )

    target_link_libraries(ComplexV ${VTK_LIBRARIES})

### Download and Build ComplexV

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

    cd ComplexV/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:

    ./ComplexV

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.