Function parsePtsCoordinate

source/MRMesh/MRIOParsing.cpp:220–275

template <typename T>
Expected<void> parsePtsCoordinate( const std::string_view& str, Vector3<T>& v, Color* c, Vector3<T>* n )
{
    using namespace boost::spirit::x3;

    int vi = 0, ci = 0, ni = 0;
    auto coord = [&] ( auto& ctx ) { v[vi++] = _attr( ctx ); };
    auto intensity = [&] ( auto& ctx ) { (void)ctx; }; // value not used
    auto color = [&] ( auto& ctx ) { ((uint8_t*)c)[ci++] = _attr( ctx ); };
    auto normal = [&] ( auto& ctx ) { (*n)[ni++] = _attr( ctx ); };

    using uint8_type = uint_parser<uint8_t>;
    constexpr uint8_type uint8_ = {};
    bool r;
    if ( n != nullptr )
    {
        r = phrase_parse(
            str.begin(),
            str.end(),
            (
                floatT[coord] >> floatT[coord] >> floatT[coord] >>
                -( floatT[intensity] >>
                -( uint8_[color] >> uint8_[color] >> uint8_[color] >>
                -( floatT[normal] >> floatT[normal] >> floatT[normal] ) ) )
            ),
            ascii::space
        );
    }
    else if ( c != nullptr )
    {
        r = phrase_parse(
            str.begin(),
            str.end(),
            (
                floatT[coord] >> floatT[coord] >> floatT[coord] >>
                -( floatT[intensity] >>
                -( uint8_[color] >> uint8_[color] >> uint8_[color] ) )
            ),
            ascii::space
        );
    }
    else
    {
        r = phrase_parse(
            str.begin(),
            str.end(),
            (
                floatT[coord] >> floatT[coord] >> floatT[coord]
            ),
            ascii::space
        );
    }
    if ( !r )
        return unexpected( "Failed to parse vertex: " + std::string( trimRight( str.substr( 0, MaxErrorStringLen ) ) ) );

    return {};
}

template<typename T>