# TextureMapQuad

VTKExamples/Cxx/Visualization/TextureMapQuad

### Description

This example defines 4 points (coplanar) and textures them using the input image.

### Code

TextureMapQuad.cxx

    #include <vtkVersion.h>
    #include <vtkImageData.h>
    #include <vtkPointData.h>
    #include <vtkCellArray.h>
    #include <vtkJPEGReader.h>
    #include <vtkPolyDataMapper.h>
    #include <vtkPolyData.h>
    #include <vtkSmartPointer.h>
    #include <vtkTexture.h>
    #include <vtkRenderer.h>
    #include <vtkRenderWindow.h>
    #include <vtkRenderWindowInteractor.h>
    #include <vtkFloatArray.h>
    #include <vtkPolygon.h>
    #include <string>

    int main ( int argc, char *argv[] )
    {
      // Parse command line arguments
      if ( argc != 2 )
      {
        std::cerr << "Usage:" << argv[0] << " Filename" << std::endl;
        return EXIT_FAILURE;
      }

      std::string inputFilename = argv[1];

      // Read the image which will be the texture
      vtkSmartPointer<vtkJPEGReader> jPEGReader =
        vtkSmartPointer<vtkJPEGReader>::New();
      jPEGReader->SetFileName ( inputFilename.c_str() );

      // Create a plane
      vtkSmartPointer<vtkPoints> points =
        vtkSmartPointer<vtkPoints>::New();
      points->InsertNextPoint(0.0, 0.0, 0.0);
      points->InsertNextPoint(1.0, 0.0, 0.0);
      points->InsertNextPoint(1.0, 1.0, 0.0);
      points->InsertNextPoint(0.0, 2.0, 0.0);

      vtkSmartPointer<vtkCellArray> polygons =
        vtkSmartPointer<vtkCellArray>::New();
      vtkSmartPointer<vtkPolygon> polygon =
        vtkSmartPointer<vtkPolygon>::New();
      polygon->GetPointIds()->SetNumberOfIds(4); //make a quad
      polygon->GetPointIds()->SetId(0, 0);
      polygon->GetPointIds()->SetId(1, 1);
      polygon->GetPointIds()->SetId(2, 2);
      polygon->GetPointIds()->SetId(3, 3);

      polygons->InsertNextCell(polygon);

      vtkSmartPointer<vtkPolyData> quad =
        vtkSmartPointer<vtkPolyData>::New();
      quad->SetPoints(points);
      quad->SetPolys(polygons);

      vtkSmartPointer<vtkFloatArray> textureCoordinates =
        vtkSmartPointer<vtkFloatArray>::New();
      textureCoordinates->SetNumberOfComponents(3);
      textureCoordinates->SetName("TextureCoordinates");

      float tuple[3] = {0.0, 0.0, 0.0};
      textureCoordinates->InsertNextTuple(tuple);
      tuple[0] = 1.0; tuple[1] = 0.0; tuple[2] = 0.0;
      textureCoordinates->InsertNextTuple(tuple);
      tuple[0] = 1.0; tuple[1] = 1.0; tuple[2] = 0.0;
      textureCoordinates->InsertNextTuple(tuple);
      tuple[0] = 0.0; tuple[1] = 2.0; tuple[2] = 0.0;
      textureCoordinates->InsertNextTuple(tuple);

      quad->GetPointData()->SetTCoords(textureCoordinates);

      // Apply the texture
      vtkSmartPointer<vtkTexture> texture =
        vtkSmartPointer<vtkTexture>::New();
      texture->SetInputConnection(jPEGReader->GetOutputPort());

      vtkSmartPointer<vtkPolyDataMapper> mapper =
        vtkSmartPointer<vtkPolyDataMapper>::New();
    #if VTK_MAJOR_VERSION <= 5
      mapper->SetInput(quad);
    #else
      mapper->SetInputData(quad);
    #endif

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

      // Visualize the textured plane
      vtkSmartPointer<vtkRenderer> renderer =
        vtkSmartPointer<vtkRenderer>::New();
      renderer->AddActor(texturedQuad);
      renderer->SetBackground(1,1,1); // Background color white
      renderer->ResetCamera();

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

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

      renderWindow->Render();

      renderWindowInteractor->Start();

      return EXIT_SUCCESS;
    }

### CMakeLists.txt

    cmake_minimum_required(VERSION 2.8)

    PROJECT(TextureMapQuad)

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

    add_executable(TextureMapQuad MACOSX_BUNDLE TextureMapQuad.cxx)

    target_link_libraries(TextureMapQuad ${VTK_LIBRARIES})

### Download and Build TextureMapQuad

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

    cd TextureMapQuad/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:

    ./TextureMapQuad

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.