AttachAttributes

// vtk includes
#include <vtkDoubleArray.h>
#include <vtkInformation.h>
#include <vtkInformationDoubleVectorKey.h>
#include <vtkNew.h>

// std includes
#include <iostream>

int main(int, char*[])
{

  // create a 2-element array
  vtkNew<vtkDoubleArray> array;
  array->SetName("array");
  array->SetNumberOfComponents(1);
  array->SetNumberOfTuples(2);
  array->SetValue(0, 1.);
  array->SetValue(1, 2.);

  // access the info (presently none stored)
  vtkInformation* info = array->GetInformation();

  // add one attribute, a double vector
  const char* name = "myKey";
  const char* location = "MyClass"; //
  const int length = 3;
  vtkInformationDoubleVectorKey* key =
      new vtkInformationDoubleVectorKey(name, location, length);
  double values[] = {0.1, 0.2, 0.3};
  info->Set(key, values[0], values[1], values[2]);

  // extract the key
  double* vals = info->Get(key);
  std::cout << "extracted values are: " << vals[0] << ", " << vals[1] << ", "
            << vals[2] << '\n';

  return EXIT_SUCCESS;
}

cmake_minimum_required(VERSION 3.12 FATAL_ERROR)

project(AttachAttributes)

find_package(VTK COMPONENTS 
  vtkCommonCore
  QUIET
)

if (NOT VTK_FOUND)
  message("Skipping AttachAttributes: ${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(AttachAttributes MACOSX_BUNDLE AttachAttributes.cxx )
  target_link_libraries(AttachAttributes PRIVATE ${VTK_LIBRARIES})
else()
  # Prevent a "command line is too long" failure in Windows.
  set(CMAKE_NINJA_FORCE_RESPONSE_FILE "ON" CACHE BOOL "Force Ninja to use response files.")
  add_executable(AttachAttributes MACOSX_BUNDLE AttachAttributes.cxx )
  target_link_libraries(AttachAttributes PRIVATE ${VTK_LIBRARIES})
  # vtk_module_autoinit is needed
  vtk_module_autoinit(
    TARGETS AttachAttributes
    MODULES ${VTK_LIBRARIES}
    )
endif()

cd AttachAttributes/build

cmake ..

cmake -DVTK_DIR:PATH=/home/me/vtk_build ..

make

./AttachAttributes