knnGraphKNearestIterator.h

/*
 This Source Code Form is subject to the terms of the Mozilla Public
 License, v. 2.0. If a copy of the MPL was not distributed with this
 file, You can obtain one at http://mozilla.org/MPL/2.0/.
*/
 
#pragma once
 
#include "../../indexSquaredDistance.h"
#include <cstddef>
 
namespace Ponca
{
 
    template <typename ContainerPtr, typename Index>
    class KnnGraphKNearestIterator
    {
    public:
        using iterator_category = std::input_iterator_tag;
        using difference_type   = std::ptrdiff_t;
        using value_type        = Index;
        using pointer           = ContainerPtr;
        using reference         = const Index&;
        using Self              = KnnGraphKNearestIterator<ContainerPtr, Index>;
 
        PONCA_MULTIARCH KnnGraphKNearestIterator(ContainerPtr data) : m_data(data) {}
 
        PONCA_MULTIARCH KnnGraphKNearestIterator(ContainerPtr data, Index i) : m_data(data), m_i(i) {}
 
        PONCA_MULTIARCH bool operator!=(const KnnGraphKNearestIterator& other) const { return m_i != other.m_i; }
 
        PONCA_MULTIARCH bool operator==(const KnnGraphKNearestIterator& other) const { return m_i == other.m_i; }
 
        PONCA_MULTIARCH KnnGraphKNearestIterator& operator++()
        {
            ++m_i;
            return *this;
        }
 
        PONCA_MULTIARCH reference operator*() const { return m_data[m_i]; }
 
        PONCA_MULTIARCH inline Self operator++(Index)
        {
            Self tmp = *this;
            ++m_i;
            return tmp;
        }
 
        PONCA_MULTIARCH inline void operator+=(const Index i) { m_i += i; }
 
        PONCA_MULTIARCH inline Self operator+(const Index i) { return Self(m_data, m_i + i); }
 
    protected:
        ContainerPtr m_data;
        Index m_i{0};
    };
} // namespace Ponca