mesh_elements.h

/*****************************************************************************
 * VCLib                                                                     *
 * Visual Computing Library                                                  *
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 * Copyright(C) 2021-2025                                                    *
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 * ISTI - Italian National Research Council                                  *
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the              *
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 ****************************************************************************/
 
#ifndef VCL_TYPES_MESH_ELEMENTS_H
#define VCL_TYPES_MESH_ELEMENTS_H
 
#include "base.h"
 
#include <string>
 
namespace vcl {
 
struct ElemId
{
    enum Enum : uint {
        VERTEX = 0,
        FACE,
        EDGE,
        ELEMENTS_NUMBER,
    };
};
 
constexpr const char* ELEMENT_ENUM_STRINGS[ElemId::ELEMENTS_NUMBER] = {
    "Vertex",
    "Face",
    "Edge",
};
 
template<uint ELEM_ID>
struct ElementString
{
    const char* str = ELEM_ID < ElemId::ELEMENTS_NUMBER ?
                          ELEMENT_ENUM_STRINGS[ELEM_ID] :
                          nullptr;
};
 
template<uint ELEM_ID>
constexpr const char* elementEnumCString()
{
    static_assert(
        ElementString<ELEM_ID>().str != nullptr,
        "Invalid ElementIDEnum. You should specialize 'the ElementString' "
        "struct with your ELEM_ID value.");
 
    return ElementString<ELEM_ID>().str;
}
 
// Todo: make this function constexpr when upgrading to C++23.
template<uint ELEM_ID>
const std::string& elementEnumString()
{
    static const std::string str = elementEnumCString<ELEM_ID>();
 
    return str;
}
 
} // namespace vcl
 
#endif // VCL_TYPES_MESH_ELEMENTS_H