normals.h

/*****************************************************************************
 * VCLib                                                                     *
 * Visual Computing Library                                                  *
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 * Copyright(C) 2021-2025                                                    *
 * Visual Computing Lab                                                      *
 * ISTI - Italian National Research Council                                  *
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#ifndef VCL_VIEWS_MESH_COMPONENTS_NORMALS_H
#define VCL_VIEWS_MESH_COMPONENTS_NORMALS_H
 
#include <vclib/concepts/pointers.h>
#include <vclib/types.h>
 
#include <ranges>
 
namespace vcl::views {
 
namespace detail {
 
inline constexpr auto normal = [](auto&& p) -> decltype(auto) {
    if constexpr (IsPointer<decltype(p)>)
        return p->normal();
    else
        return p.normal();
};
 
struct NormalsView
{
    constexpr NormalsView() = default;
 
    template<std::ranges::range R>
    friend constexpr auto operator|(R&& r, NormalsView)
    {
        return std::forward<R>(r) | std::views::transform(normal);
    }
};
 
} // namespace detail
 
inline constexpr detail::NormalsView normals;
 
} // namespace vcl::views
 
#endif // VCL_VIEWS_MESH_COMPONENTS_NORMALS_H