# ProjectedTexture

VTKExamples/Cxx/Texture/ProjectedTexture

### Description vtkProjectedTexture is tricky to set up. Picking the right parameters will take some iterations. The example uses vtkFrustumSource to help understand the parameters.

Cite

This example was inspired by Thomas Kilgus, German Cancer Research Center (DKFZ), Div. Medical and Biological Informatics, Junior group: Computer-assisted Interventions (E131), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany

### Code

ProjectedTexture.cxx

    #include <vtkSmartPointer.h>

    #include <vtkProjectedTexture.h>
    #include <vtkCamera.h>
    #include <vtkFrustumSource.h>
    #include <vtkPlanes.h>
    #include <vtkMath.h>

    #include <vtkImageReader2Factory.h>
    #include <vtkImageReader2.h>
    #include <vtkTexture.h>
    #include <vtkPointData.h>
    #include <vtkImageData.h>

    #include <vtkBYUReader.h>
    #include <vtkOBJReader.h>
    #include <vtkPLYReader.h>
    #include <vtkPolyDataReader.h>
    #include <vtkSTLReader.h>
    #include <vtkXMLPolyDataReader.h>
    #include <vtkSphereSource.h>

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

    #include <vtkNamedColors.h>

    #include <vtksys/SystemTools.hxx>

    namespace
    {
    vtkSmartPointer<vtkPolyData> ReadPolyData(const char *fileName);
    }

    int main (int argc, char *argv[])
    {
      if (argc < 3)
      {
        std::cout << "Usage: " << argv[0] << " polydata texture" << std::endl;
        return EXIT_FAILURE;
      }
      vtkSmartPointer<vtkPolyData> polyData = ReadPolyData(argc > 1 ? argv[1] : "");;

      vtkSmartPointer<vtkImageReader2Factory> readerFactory =
        vtkSmartPointer<vtkImageReader2Factory>::New();
      vtkSmartPointer<vtkImageReader2> textureFile =
        readerFactory->CreateImageReader2(argv[2]);
      textureFile->SetFileName(argv[2]);
      textureFile->Update();

      vtkSmartPointer<vtkNamedColors> colors =
        vtkSmartPointer<vtkNamedColors>::New();

      double center[3];
      polyData->GetCenter(center);
      std::cout << "Center: "
                << center[0] << ", "
                << center[1] << ", "
                << center[2] << std::endl;
      vtkSmartPointer<vtkCamera> camera =
        vtkSmartPointer<vtkCamera>::New();
      camera->SetPosition(center[0], center[1] + .0375, center[2] +.5);
      camera->SetFocalPoint(center[0], center[1] + .0375, center[2]);
      camera->Azimuth(-45);
      camera->Roll(-90);
      camera->SetClippingRange(.5, .6);
      double planesArray[24];

      camera->GetFrustumPlanes(1.0, planesArray);

      //Settings for vtkProjectedTexture

      double aspect[3];
      aspect[1] = 1.0;
      aspect[2] = 1.0;
      aspect[0] = 1.0;
    //(1.0/ (vtkMath::RadiansFromDegrees(std::tan(camera->GetViewAngle())))) / 2.0;
      std::cout << "Aspect: "
                << aspect[0] << ", "
                << aspect[1] << ", "
                << aspect[2] << std::endl;

      vtkSmartPointer<vtkProjectedTexture>  projectedTexture =
        vtkSmartPointer<vtkProjectedTexture>::New();

      projectedTexture->SetAspectRatio(aspect);
      projectedTexture->SetPosition(camera->GetPosition());
      projectedTexture->SetFocalPoint(camera->GetFocalPoint());
      projectedTexture->SetUp(
        camera->GetViewUp()[0],
        camera->GetViewUp()[1],
        camera->GetViewUp()[2]);

      projectedTexture->SetInputData( polyData); //this can be the same as the one to project on
      projectedTexture->Update();

      //Map Texture on Surface
      polyData->GetPointData()->SetTCoords(
        projectedTexture->GetOutput()->GetPointData()->GetTCoords());

      vtkSmartPointer<vtkTexture> texture =
        vtkSmartPointer<vtkTexture>::New();
      texture->SetInputData(textureFile->GetOutput());

      vtkSmartPointer<vtkPolyDataMapper> mapper =
        vtkSmartPointer<vtkPolyDataMapper>::New();
      mapper->SetInputData(polyData);

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

      vtkSmartPointer<vtkPlanes> planes =
        vtkSmartPointer<vtkPlanes>::New();
      planes->SetFrustumPlanes(planesArray);

      vtkSmartPointer<vtkFrustumSource> frustumSource =
        vtkSmartPointer<vtkFrustumSource>::New();
      frustumSource->ShowLinesOff();
      frustumSource->SetPlanes(planes);
      frustumSource->Update();

      vtkSmartPointer<vtkPolyDataMapper> frustumMapper =
        vtkSmartPointer<vtkPolyDataMapper>::New();
      frustumMapper->SetInputConnection(frustumSource->GetOutputPort());

      vtkSmartPointer<vtkActor> frustumActor =
        vtkSmartPointer<vtkActor>::New();
      frustumActor->SetMapper(frustumMapper);
      frustumActor->GetProperty()->EdgeVisibilityOn();
      frustumActor->GetProperty()->SetColor(colors->GetColor3d("Banana").GetData());
      frustumActor->GetProperty()->SetOpacity(.5);
      frustumActor->GetProperty()->SetRepresentationToWireframe();

      vtkSmartPointer<vtkRenderer> renderer =
        vtkSmartPointer<vtkRenderer>::New();
      renderer->AddActor(actor);
      renderer->AddActor(frustumActor);
      renderer->SetBackground(colors->GetColor3d("SlateGray").GetData());
      renderer->SetActiveCamera(camera);
      camera->Azimuth(180);
      camera->Roll(-90);
      renderer->ResetCameraClippingRange();

      vtkSmartPointer<vtkRenderWindow> renderWindow =
        vtkSmartPointer<vtkRenderWindow>::New();
      renderWindow->AddRenderer( renderer );

      vtkSmartPointer<vtkRenderWindowInteractor> renWinInteractor =
        vtkSmartPointer<vtkRenderWindowInteractor>::New();
      renWinInteractor->SetRenderWindow( renderWindow );

      renderWindow->Render();
      renWinInteractor->Start();

      return EXIT_SUCCESS;
    }

    namespace
    {
    vtkSmartPointer<vtkPolyData> ReadPolyData(const char *fileName)
    {
      vtkSmartPointer<vtkPolyData> polyData;
      std::string extension = vtksys::SystemTools::GetFilenameExtension(std::string(fileName));
      if (extension == ".ply")
      {
        vtkSmartPointer<vtkPLYReader> reader =
          vtkSmartPointer<vtkPLYReader>::New();
        reader->SetFileName (fileName);
        reader->Update();
        polyData = reader->GetOutput();
      }
      else if (extension == ".vtp")
      {
        vtkSmartPointer<vtkXMLPolyDataReader> reader =
          vtkSmartPointer<vtkXMLPolyDataReader>::New();
        reader->SetFileName (fileName);
        reader->Update();
        polyData = reader->GetOutput();
      }
      else if (extension == ".obj")
      {
        vtkSmartPointer<vtkOBJReader> reader =
          vtkSmartPointer<vtkOBJReader>::New();
        reader->SetFileName (fileName);
        reader->Update();
        polyData = reader->GetOutput();
      }
      else if (extension == ".stl")
      {
        vtkSmartPointer<vtkSTLReader> reader =
          vtkSmartPointer<vtkSTLReader>::New();
        reader->SetFileName (fileName);
        reader->Update();
        polyData = reader->GetOutput();
      }
      else if (extension == ".vtk")
      {
        vtkSmartPointer<vtkPolyDataReader> reader =
          vtkSmartPointer<vtkPolyDataReader>::New();
        reader->SetFileName (fileName);
        reader->Update();
        polyData = reader->GetOutput();
      }
      else if (extension == ".g")
      {
        vtkSmartPointer<vtkBYUReader> reader =
          vtkSmartPointer<vtkBYUReader>::New();
        reader->SetGeometryFileName (fileName);
        reader->Update();
        polyData = reader->GetOutput();
      }
      else
      {
        vtkSmartPointer<vtkSphereSource> source =
          vtkSmartPointer<vtkSphereSource>::New();
        source->Update();
        polyData = source->GetOutput();
      }
      return polyData;
    }
    }

### CMakeLists.txt

    cmake_minimum_required(VERSION 2.8)

    PROJECT(ProjectedTexture)

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

    add_executable(ProjectedTexture MACOSX_BUNDLE ProjectedTexture.cxx )

    target_link_libraries(ProjectedTexture ${VTK_LIBRARIES})

### Download and Build ProjectedTexture

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

    cd ProjectedTexture/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:

    ./ProjectedTexture

WINDOWS USERS

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