element.h

/*****************************************************************************
 * VCLib                                                                     *
 * Visual Computing Library                                                  *
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 * Copyright(C) 2021-2025                                                    *
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#ifndef VCL_VIEWS_MESH_ELEMENTS_ELEMENT_H
#define VCL_VIEWS_MESH_ELEMENTS_ELEMENT_H
 
#include <vclib/concepts/pointers.h>
#include <vclib/types.h>
 
#include <ranges>
 
namespace vcl::views {
 
namespace detail {
 
inline constexpr auto index = [](auto&& p) -> uint {
    if constexpr (IsPointer<decltype(p)>) {
        if (p == nullptr) [[unlikely]]
            return UINT_NULL;
        else
            return p->index();
    }
    else
        return p.index();
};
 
struct IndexView
{
    constexpr IndexView() = default;
 
    template<std::ranges::range R>
    friend constexpr auto operator|(R&& r, IndexView)
    {
        return std::forward<R>(r) | std::views::transform(index);
    }
};
 
} // namespace detail
 
inline constexpr detail::IndexView indices;
 
} // namespace vcl::views
 
#endif // VCL_VIEWS_MESH_ELEMENTS_ELEMENT_H