knnGraphKNearestQuery.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 "../../query.h"
#include "../Iterator/knnGraphRangeIterator.h"
#include <vector>
 
namespace Ponca
{
 
    template <typename Traits>
    class KnnGraphBase; // Need forward declaration to avoid mutual inclusion
 
#ifndef PARSED_WITH_DOXYGEN
    struct KnnGraphQueryOutputType : public QueryOutputBase
    {
        using OutputParameter = typename QueryOutputBase::DummyOutputParameter;
    };
#endif
 
    template <typename Traits>
    class KnnGraphKNearestQuery
#ifdef PARSED_WITH_DOXYGEN
        : public KNearestIndexQuery<typename Traits::IndexType, typename Traits::DataPoint::Scalar>
#else
        // we skip output because we don't need it: k is static, and already stored in the index array
        : public Query<QueryInputIsIndex<typename Traits::IndexType>, KnnGraphQueryOutputType>
#endif
    {
    public:
        using Iterator = typename Traits::IndexContainer::const_iterator;
#ifdef PARSED_WITH_DOXYGEN
        using QueryType = KNearestIndexQuery<typename Traits::IndexType, typename Traits::DataPoint::Scalar>;
#else
        using QueryType = Query<QueryInputIsIndex<typename Traits::IndexType>, KnnGraphQueryOutputType>;
#endif
        using Self = KnnGraphKNearestQuery<Traits>;
 
    public:
        inline KnnGraphKNearestQuery(const KnnGraphBase<Traits>* graph, int index) : QueryType(index), m_graph(graph) {}
 
        inline Self& operator()(int index) { return QueryType::template operator()<Self>(index); }
 
        inline Iterator begin() const { return m_graph->index_data().begin() + QueryType::input() * m_graph->k(); }
 
        inline Iterator end() const { return m_graph->index_data().begin() + (QueryType::input() + 1) * m_graph->k(); }
 
    protected:
        const KnnGraphBase<Traits>* m_graph{nullptr};
    };
 
} // namespace Ponca