Function parseObjCoordinate

source/MRMesh/MRIOParsing.cpp:185–217

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

    int i = 0;
    auto coord = [&] ( auto& ctx ) { v[i++] = _attr( ctx ); };
    int j = 0;
    auto color = [&] ( auto& ctx ) { if ( c ) ( *c )[j++] = _attr( ctx ); };

    bool r;
    if ( c != nullptr )
    {
        r = phrase_parse(
            str.begin(),
            str.end(),
            ( 'v' >> floatT[coord] >> floatT[coord] >> floatT[coord] >> -( floatT[color] >> floatT[color] >> floatT[color] ) ),
            ascii::space
        );
    }
    else
    {
        r = phrase_parse(
            str.begin(),
            str.end(),
            ( 'v' >> 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>
Expected<void> parsePtsCoordinate( const std::string_view& str, Vector3<T>& v, Color* c, Vector3<T>* n )