Method BuildSelectionCache

Rendering/OpenGL2/vtkOpenGLPolyDataMapper.cxx:4419–4461

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//------------------------------------------------------------------------------
void vtkOpenGLPolyDataMapper::BuildSelectionCache(
  const char* arrayName, bool selectingPoints, vtkPolyData* poly)
{
  if (arrayName &&
    (this->SelectionCacheForPoints != selectingPoints || this->SelectionCacheName != arrayName ||
      this->SelectionCacheTime < poly->GetMTime() || poly != this->SelectionPolyData))
  {
    // the cache needs a rebuild
    this->SelectionCache.clear();

    vtkDataSetAttributes* attr = selectingPoints
      ? static_cast<vtkDataSetAttributes*>(poly->GetPointData())
      : static_cast<vtkDataSetAttributes*>(poly->GetCellData());

    auto idArray = vtkIdTypeArray::SafeDownCast(attr->GetArray(arrayName));
    vtkDataArray* compositeArray = attr->GetArray(this->CompositeIdArrayName);
    vtkDataArray* processArray = attr->GetArray(this->ProcessIdArrayName);

    // a selection cache is built here to map a tuple (process id, composite id, value id) to the
    // the selected id. This will speed up look-ups at runtime.
    if (idArray && idArray->GetNumberOfComponents() == 1)
    {
      using UIntArrays =
        vtkTypeList::Create<vtkAOSDataArrayTemplate<unsigned int>, vtkConstantArray<unsigned int>>;
      using Dispatcher = vtkArrayDispatch::Dispatch2ByArray<UIntArrays, UIntArrays>;
      CompositeProcessFunctor functor;
      if (!Dispatcher::Execute(
            compositeArray, processArray, functor, idArray, this->SelectionCache))
      {
        if ((!compositeArray || compositeArray->GetDataType() == VTK_UNSIGNED_INT) &&
          (!processArray || processArray->GetDataType() == VTK_UNSIGNED_INT))
        {
          functor(compositeArray, processArray, idArray, this->SelectionCache);
        }
      }
    }

    this->SelectionCacheForPoints = selectingPoints;
    this->SelectionCacheName = arrayName;
    this->SelectionCacheTime = poly->GetMTime();
    this->SelectionPolyData = poly;
  }
}

//------------------------------------------------------------------------------
void vtkOpenGLPolyDataMapper::ShallowCopy(vtkAbstractMapper* mapper)