vtk-m/vtkm/cont/ArrayPortalToIterators.h
2019-04-17 10:57:13 -06:00

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3.0 KiB
C++

//============================================================================
// Copyright (c) Kitware, Inc.
// All rights reserved.
// See LICENSE.txt for details.
//
// This software is distributed WITHOUT ANY WARRANTY; without even
// the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
// PURPOSE. See the above copyright notice for more information.
//============================================================================
#ifndef vtk_m_cont_ArrayPortalToIterators_h
#define vtk_m_cont_ArrayPortalToIterators_h
#include <vtkm/cont/ArrayPortal.h>
#include <vtkm/cont/internal/IteratorFromArrayPortal.h>
namespace vtkm
{
namespace cont
{
/// \brief Convert an \c ArrayPortal to STL iterators.
///
/// \c ArrayPortalToIterators is a class that holds an \c ArrayPortal and
/// builds iterators that access the data in the \c ArrayPortal. The point of
/// this class is to use an \c ArrayPortal with generic functions that expect
/// STL iterators such as STL algorithms or Thrust operations.
///
/// The default template implementation constructs iterators that provide
/// values through the \c ArrayPortal itself. This class can be specialized to
/// provide iterators that more directly access the data. For example, \c
/// ArrayPortalFromIterator has a specialization to return the original
/// iterators.
///
template <typename PortalType>
class ArrayPortalToIterators
{
public:
/// \c ArrayPortaltoIterators should be constructed with an instance of
/// the array portal.
///
VTKM_SUPPRESS_EXEC_WARNINGS
VTKM_EXEC_CONT
ArrayPortalToIterators(const PortalType& portal)
: Portal(portal)
{
}
/// The type of the iterator.
///
using IteratorType = vtkm::cont::internal::IteratorFromArrayPortal<PortalType>;
/// Returns an iterator pointing to the beginning of the ArrayPortal.
///
VTKM_SUPPRESS_EXEC_WARNINGS
VTKM_EXEC_CONT
IteratorType GetBegin() const { return vtkm::cont::internal::make_IteratorBegin(this->Portal); }
/// Returns an iterator pointing to one past the end of the ArrayPortal.
///
VTKM_SUPPRESS_EXEC_WARNINGS
VTKM_EXEC_CONT
IteratorType GetEnd() const { return vtkm::cont::internal::make_IteratorEnd(this->Portal); }
private:
PortalType Portal;
};
/// Convenience function for converting an ArrayPortal to a begin iterator.
///
VTKM_SUPPRESS_EXEC_WARNINGS
template <typename PortalType>
VTKM_EXEC_CONT typename vtkm::cont::ArrayPortalToIterators<PortalType>::IteratorType
ArrayPortalToIteratorBegin(const PortalType& portal)
{
vtkm::cont::ArrayPortalToIterators<PortalType> iterators(portal);
return iterators.GetBegin();
}
/// Convenience function for converting an ArrayPortal to an end iterator.
///
VTKM_SUPPRESS_EXEC_WARNINGS
template <typename PortalType>
VTKM_EXEC_CONT typename vtkm::cont::ArrayPortalToIterators<PortalType>::IteratorType
ArrayPortalToIteratorEnd(const PortalType& portal)
{
vtkm::cont::ArrayPortalToIterators<PortalType> iterators(portal);
return iterators.GetEnd();
}
}
} // namespace vtkm::cont
#endif //vtk_m_cont_ArrayPortalToIterators_h