functions.h

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 * VCLib                                                                     *
 * Visual Computing Library                                                  *
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 * Copyright(C) 2021-2025                                                    *
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#ifndef VCL_ALGORITHMS_CORE_DISTANCE_FUNCTIONS_H
#define VCL_ALGORITHMS_CORE_DISTANCE_FUNCTIONS_H
 
#include "distance.h"
 
namespace vcl {
 
namespace detail {
 
template<typename Obj1, typename Obj2, typename ST>
concept BoundedDistFunctionExists =
    requires (Obj1 o1, Obj2 o2, ST v) { boundedDistance(o1, o2, v); };
 
} // namespace detail
 
template<typename Obj1, typename Obj2>
auto distFunction()
{
    auto f = [](const Obj1& o1, const Obj2& o2) {
        return distance(o1, o2);
    };
 
    return f;
}
 
template<typename Obj1, typename Obj2, typename ScalarType = double>
auto boundedDistFunction()
{
    if constexpr (detail::BoundedDistFunctionExists<Obj1, Obj2, ScalarType>) {
        auto f = [](const Obj1& o1, const Obj2& o2, ScalarType s) {
            return boundedDistance(o1, o2, s);
        };
 
        return f;
    }
    else {
        auto f = [](const Obj1& o1, const Obj2& o2, ScalarType) {
            return distance(o1, o2);
        };
 
        return f;
    }
}
 
} // namespace vcl
 
#endif // VCL_ALGORITHMS_CORE_DISTANCE_FUNCTIONS_H