# CustomDenseArray

VTKExamples/Cxx/Utilities/CustomDenseArray

### Description

The only thing you have to do to enable your class to work with vtkDenseArray is add a single line:

operator vtkVariant() const { return vtkVariant(); }

### Code

CustomDenseArray.cxx

    #include <vtkSmartPointer.h>
    #include <vtkDenseArray.h>

    struct Point
    {
      double x,y;

      operator vtkVariant() const { return vtkVariant(); }
    };

    int main(int, char *[])
    {
      Point point;
      point.x = 1.0;
      point.y = 2.0;

      std::cout << point.x << " " << point.y << std::endl;

      vtkSmartPointer<vtkDenseArray<Point> > array =
        vtkSmartPointer<vtkDenseArray<Point> >::New();
      array->Resize(5,5);

      array->SetValue(4,4, point);

      Point retrievedPoint = array->GetValue(4,4);
      std::cout << retrievedPoint.x << " " << retrievedPoint.y << std::endl;

      return EXIT_SUCCESS;
    }

### CMakeLists.txt

    cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

    project(CustomDenseArray)

    find_package(VTK COMPONENTS
      vtkCommonCore QUIET)
    if (NOT VTK_FOUND)
      message("Skipping CustomDenseArray: ${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(CustomDenseArray MACOSX_BUNDLE CustomDenseArray.cxx )
      target_link_libraries(CustomDenseArray PRIVATE ${VTK_LIBRARIES})
    else ()
      # include all components
      add_executable(CustomDenseArray MACOSX_BUNDLE CustomDenseArray.cxx )
      target_link_libraries(CustomDenseArray PRIVATE ${VTK_LIBRARIES})
      # vtk_module_autoinit is needed
      vtk_module_autoinit(
        TARGETS CustomDenseArray
        MODULES ${VTK_LIBRARIES}
        )
    endif ()

### Download and Build CustomDenseArray

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

    cd CustomDenseArray/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:

    ./CustomDenseArray

WINDOWS USERS

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