Function GetSubRange

Common/Core/vtkDataArrayValueRange_Generic.h:856–913

// ValueRange
template <typename ArrayTypeT, ComponentIdType TupleSize, typename ForceValueTypeForVtkDataArray>
struct ValueRange
{
private:
  static_assert(IsValidTupleSize<TupleSize>::value, "Invalid tuple size.");
  static_assert(IsVtkDataArray<ArrayTypeT>::value, "Invalid array type.");

  using IdStorageType = IdStorage<TupleSize>;
  using NumCompsType = GenericTupleSize<TupleSize>;

public:
  using ArrayType = ArrayTypeT;
  using ValueType = GetAPIType<ArrayType, ForceValueTypeForVtkDataArray>;

  using IteratorType = ValueIterator<ArrayType, TupleSize, ForceValueTypeForVtkDataArray>;
  using ConstIteratorType = ConstValueIterator<ArrayType, TupleSize, ForceValueTypeForVtkDataArray>;
  using ReferenceType = ValueReference<ArrayType, TupleSize, ForceValueTypeForVtkDataArray>;
  using ConstReferenceType =
    ConstValueReference<ArrayType, TupleSize, ForceValueTypeForVtkDataArray>;

  // May be DynamicTupleSize, or the actual tuple size.
  constexpr static ComponentIdType TupleSizeTag = TupleSize;

  // STL-compat
  using value_type = ValueType;
  using size_type = ValueIdType;
  using iterator = IteratorType;
  using const_iterator = ConstIteratorType;
  using reference = ReferenceType;
  using const_reference = ConstReferenceType;

  VTK_ITER_INLINE
  ValueRange() noexcept = default;

  VTK_ITER_INLINE
  ValueRange(ArrayType* arr, ValueIdType beginValue, ValueIdType endValue) noexcept
    : Array(arr)
    , NumComps(arr)
    , BeginValue(beginValue, this->NumComps)
    , EndValue(endValue, this->NumComps)
  {
    assert(this->Array);
    assert(beginValue >= 0 && beginValue <= endValue);
    assert(endValue >= 0 && endValue <= this->Array->GetNumberOfValues());
    if constexpr (IsStaticTupleSize<TupleSize>::value)
    {
      assert(arr->GetNumberOfComponents() == TupleSize);
    }
  }

  VTK_ITER_INLINE
  ValueRange GetSubRange(ValueIdType beginValue = 0, ValueIdType endValue = -1) const noexcept
  {
    const ValueIdType realBegin = this->BeginValue.GetValueId() + beginValue;
    const ValueIdType realEnd =
      endValue >= 0 ? this->BeginValue.GetValueId() + endValue : this->EndValue.GetValueId();

    return ValueRange{ this->Array, realBegin, realEnd };
  }