vtkDataArrayRange.h

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// SPDX-FileCopyrightText: Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
// SPDX-License-Identifier: BSD-3-Clause

#ifndef vtkDataArrayRange_h
#define vtkDataArrayRange_h

#include "vtkAOSDataArrayTemplate.h"
#include "vtkDataArray.h"
#include "vtkDataArrayMeta.h"
#include "vtkDataArrayTupleRange_AOS.h"
#include "vtkDataArrayTupleRange_Generic.h"
#include "vtkDataArrayValueRange_AOS.h"
#include "vtkDataArrayValueRange_Generic.h"
#include "vtkMeta.h"
#include "vtkSmartPointer.h"

#include <cassert>
#include <iterator>
#include <type_traits>

VTK_ITER_OPTIMIZE_START

namespace vtk
{
namespace detail
{
VTK_ABI_NAMESPACE_BEGIN

// Internal detail: This utility is not directly needed by users of
// DataArrayRange.
//
// These classes are used to detect when specializations exist for a given
// array type. They are necessary because given:
//
// template <typename ArrayType> class SomeTemplateClass;
// template <typename T> class SomeTemplateClass<vtkAOSDataArrayTemplate<T>>;
//
// SomeTemplateClass<vtkFloatArray> will pick the generic version, as ArrayType
// is a better match than vtkAOSDataArrayTemplate<T>. This class works around
// that by using Declare[Tuple|Value]RangeSpecialization functions that map an
// input ArrayTypePtr and tuple size to a specific version of the appropriate
// Range.
template <typename ArrayTypePtr, ComponentIdType TupleSize>
struct SelectTupleRange
{
private:
  // Allow this to work with vtkNew, vtkSmartPointer, etc.
  using ArrayType = typename detail::StripPointers<ArrayTypePtr>::type;

  static_assert(detail::IsValidTupleSize<TupleSize>::value, "Invalid tuple size.");
  static_assert(detail::IsVtkArray<ArrayType>::value, "Invalid array type.");

public:
  using type =
    std::decay_t<decltype(vtk::detail::DeclareTupleRangeSpecialization<ArrayType, TupleSize>(
      std::declval<ArrayType*>()))>;
};

template <typename ArrayTypePtr, ComponentIdType TupleSize,
  typename ForceValueTypeForVtkDataArray = double>
struct SelectValueRange
{
private:
  // Allow this to work with vtkNew, vtkSmartPointer, etc.
  using ArrayType = typename detail::StripPointers<ArrayTypePtr>::type;

  static_assert(detail::IsValidTupleSize<TupleSize>::value, "Invalid tuple size.");
  static_assert(detail::IsVtkArray<ArrayType>::value, "Invalid array type.");

public:
  using type =
    std::remove_reference_t<decltype(vtk::detail::DeclareValueRangeSpecialization<ArrayType,
      TupleSize, ForceValueTypeForVtkDataArray>(std::declval<ArrayType*>()))>;
};

VTK_ABI_NAMESPACE_END
} // end namespace detail

VTK_ABI_NAMESPACE_BEGIN
template <ComponentIdType TupleSize = detail::DynamicTupleSize,
  typename ArrayTypePtr = vtkDataArray*>
VTK_ITER_INLINE auto DataArrayTupleRange(const ArrayTypePtr& array, TupleIdType start = -1,
  TupleIdType end = -1) -> typename detail::SelectTupleRange<ArrayTypePtr, TupleSize>::type
{
  // Lookup specializations:
  using RangeType = typename detail::SelectTupleRange<ArrayTypePtr, TupleSize>::type;

  assert(array);

  return RangeType(array, start < 0 ? 0 : start, end < 0 ? array->GetNumberOfTuples() : end);
}

template <ComponentIdType TupleSize = detail::DynamicTupleSize,
  typename ForceValueTypeForVtkDataArray = double, typename ArrayTypePtr = vtkDataArray*>
VTK_ITER_INLINE auto DataArrayValueRange(
  const ArrayTypePtr& array, ValueIdType start = -1, ValueIdType end = -1) ->
  typename detail::SelectValueRange<ArrayTypePtr, TupleSize, ForceValueTypeForVtkDataArray>::type
{
  using RangeType =
    typename detail::SelectValueRange<ArrayTypePtr, TupleSize, ForceValueTypeForVtkDataArray>::type;

  assert(array);

  return RangeType(array, start < 0 ? 0 : start, end < 0 ? array->GetNumberOfValues() : end);
}

VTK_ABI_NAMESPACE_END
} // end namespace vtk

VTK_ITER_OPTIMIZE_END

#endif // vtkDataArrayRange_h

// VTK-HeaderTest-Exclude: vtkDataArrayRange.h