Хеш таблица, групировка значений

size_t CalcHash(const Material& material)
{
    size_t hash = 0;
    if (!material.m_AmbientMapName.empty())
        hash += 1;
    if (!material.m_DiffuseMapName.empty())
        hash += 2;
    if (!material.m_NormalMapName.empty())
        hash += 3;
    if (!material.m_ShininessMapName.empty())
        hash += 4;
    if (!material.m_SpecularMapName.empty())
        hash += 5;
 
        return hash;
}

std::vector GroupMaterial(std::vector objects)
{
    std::vector g_O_material;
    ..............
 
    return g_O_material;
}

std::vector<std::vector<std::shared_ptr<GameObject>>> GroupGameObjectsByMaterial(std::shared_ptr<std::vector<std::shared_ptr<GameObject>>> gameObjects)
{
    for (std::shared_ptr<GameObject> gameObject : *gameObjects)
    {
        std::sort(*gameObjects->begin(), *gameObjects->end(), Comp);
    }
    std::vector<std::vector<std::shared_ptr<GameObject>>> gameObjectsByMaterial;
    gameObjectsByMaterial.reserve(gameObjects->size);
 
    for (auto it = gameObjects->begin(); it != gameObjects->end(); ++it)
    {
        if (it != gameObjectsByMaterial[gameObjectsByMaterial.size - 1])
        {
            gameObjectsByMaterial.push_back(it);
        }
    }
    return gameObjectsByMaterial;
}