WriteVTI

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Code¶

WriteVTI.cxx

#include <vtkSmartPointer.h>
#include <vtkProperty.h>
#include <vtkXMLImageDataWriter.h>
#include <vtkXMLImageDataReader.h>
#include <vtkImageData.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkImageDataGeometryFilter.h>
#include <vtkRenderWindow.h>
#include <vtkActor.h>
#include <vtkPolyDataMapper.h>

int main(int argc, char *argv[])
{
  // Parse command line arguments
  if(argc != 2)
  {
    std::cout << "Required arguments: filename.vti" << std::endl;
    return EXIT_FAILURE;
  }

  std::string filename = argv[1];

  vtkSmartPointer<vtkImageData> imageData =
    vtkSmartPointer<vtkImageData>::New();
  imageData->SetDimensions(3,4,5);
  imageData->AllocateScalars(VTK_DOUBLE, 1);

  int* dims = imageData->GetDimensions();

  // Fill every entry of the image data with "2.0"
  for (int z = 0; z < dims[2]; z++)
  {
    for (int y = 0; y < dims[1]; y++)
    {
      for (int x = 0; x < dims[0]; x++)
      {
        double* pixel = static_cast<double*>(imageData->GetScalarPointer(x,y,z));
        pixel[0] = 2.0;
      }
    }
  }

  vtkSmartPointer<vtkXMLImageDataWriter> writer =
    vtkSmartPointer<vtkXMLImageDataWriter>::New();
  writer->SetFileName(filename.c_str());
  writer->SetInputData(imageData);
  writer->Write();

  // Read the file (to test that it was written correctly)
  vtkSmartPointer<vtkXMLImageDataReader> reader =
    vtkSmartPointer<vtkXMLImageDataReader>::New();
  reader->SetFileName(filename.c_str());
  reader->Update();

  // Convert the image to a polydata
  vtkSmartPointer<vtkImageDataGeometryFilter> imageDataGeometryFilter =
    vtkSmartPointer<vtkImageDataGeometryFilter>::New();
  imageDataGeometryFilter->SetInputConnection(reader->GetOutputPort());
  imageDataGeometryFilter->Update();

  vtkSmartPointer<vtkPolyDataMapper> mapper =
    vtkSmartPointer<vtkPolyDataMapper>::New();
  mapper->SetInputConnection(imageDataGeometryFilter->GetOutputPort());

  vtkSmartPointer<vtkActor> actor =
    vtkSmartPointer<vtkActor>::New();
  actor->SetMapper(mapper);
  actor->GetProperty()->SetPointSize(3);

  // Setup rendering
  vtkSmartPointer<vtkRenderer> renderer =
    vtkSmartPointer<vtkRenderer>::New();
  renderer->AddActor(actor);
  renderer->SetBackground(1,1,1);
  renderer->ResetCamera();

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

  vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
    vtkSmartPointer<vtkRenderWindowInteractor>::New();

  renderWindowInteractor->SetRenderWindow(renderWindow);
  renderWindow->Render();
  renderWindowInteractor->Initialize();
  renderWindowInteractor->Start();

  return EXIT_SUCCESS;
}

CMakeLists.txt¶

cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

project(WriteVTI)

find_package(VTK COMPONENTS 
  vtkCommonCore
  vtkCommonDataModel
  vtkFiltersGeometry
  vtkIOXML
  vtkInteractionStyle
  vtkRenderingContextOpenGL2
  vtkRenderingCore
  vtkRenderingFreeType
  vtkRenderingGL2PSOpenGL2
  vtkRenderingOpenGL2 QUIET)
if (NOT VTK_FOUND)
  message("Skipping WriteVTI: ${VTK_NOT_FOUND_MESSAGE}")
  return ()
endif()
message (STATUS "VTK_VERSION: ${VTK_VERSION}")
if (VTK_VERSION VERSION_LESS "8.90.0")
  # old system
  include(${VTK_USE_FILE})
  add_executable(WriteVTI MACOSX_BUNDLE WriteVTI.cxx )
  target_link_libraries(WriteVTI PRIVATE ${VTK_LIBRARIES})
else ()
  # include all components
  add_executable(WriteVTI MACOSX_BUNDLE WriteVTI.cxx )
  target_link_libraries(WriteVTI PRIVATE ${VTK_LIBRARIES})
  # vtk_module_autoinit is needed
  vtk_module_autoinit(
    TARGETS WriteVTI
    MODULES ${VTK_LIBRARIES}
    )
endif ()

Download and Build WriteVTI¶

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

cd WriteVTI/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:

./WriteVTI

WINDOWS USERS

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