pointset_locator.h

// Description: Locator of a point-set
// DocumentationOf: pointset_concept.h

#ifndef PASTELSYS_POINTSET_LOCATOR_H
#define PASTELSYS_POINTSET_LOCATOR_H

#include "pastel/sys/pointset/pointset_concept.h"
#include "pastel/sys/point/point_concept.h"
#include "pastel/sys/locator/location_set.h"
#include "pastel/sys/range/range_concept.h"
#include "pastel/sys/locator/default_locator.h"

namespace Pastel
{

    template <typename T>
    concept HasMemberPointSetLocator__ = requires(T t) {
        {addConst(t).pointSetLocator()} -> Locator_Concept;    
    };

    template <typename T>
    concept HasMemberPointSetLocator_ = 
        HasMemberPointSetLocator__<RemoveCvRef<T>>;

    template <typename Type>
    using HasMemberPointSetLocator = 
        std::bool_constant<HasMemberPointSetLocator_<Type>>;

}

namespace Pastel
{

    //! Returns the member-locator of a point-set.
    template <HasMemberPointSetLocator_ Type>
    decltype(auto) pointSetLocator(Type&& that)
    {
        return std::forward<Type>(that).pointSetLocator();
    }

    //! Returns the default locator of point-set elements.
    template <Range_Concept Range>
    requires
        (Point_Concept<Range_Value<Range>> &&
        // Give priority to the member-locator.
        !HasMemberPointSetLocator<Range>::value)
    decltype(auto) pointSetLocator(const Range& set)
    {
        using Point = Range_Value<Range>;
        using Real = Point_Real<Point>;
        static constexpr int N = Point_N<Point>::value;

        return Default_Locator<Point, Real, N>(N);
    }

}

namespace Pastel
{

    template <typename PointSet>
    using PointSet_Locator =
        RemoveCvRef<decltype(pointSetLocator(std::declval<PointSet>()))>;

}

#endif