Function loadModelsFromObj

source/MRMesh/MRMeshLoadObj.cpp:967–1262

}

Expected<std::vector<MeshLoad::NamedMesh>> loadModelsFromObj(
    const std::filesystem::path& dir,
    bool mergeAllObjects,
    const char* data,
    const std::vector<size_t>& newlines,
    const std::vector<ElementGroup<ObjElement>>& groups,
    const MeshLoad::ObjLoadSettings& settings )
{
    MR_TIMER;
    Vector<Vector3d,VertId> points; // flat list of all points in this object scope
    std::vector<Color> colors; // flat list of all colors in this object scope
    std::vector<UVCoord> uvCoords; // flat list of all uv coords in this object scope

    size_t numPoints = 0;
    size_t numUVs = 0;
    size_t numFaces = 0;
    bool colorChecked = false;
    bool hasColors = false;

    Expected<MtlLibrary> mtl = unexpected( "absent" ); // all materials

    std::string parseError;

    Timer timer( "prepare groups" ); // calculate sizes and read material

    auto sb = subprogress( settings.callback, 0.0f, 0.2f );
    int groupId = 0;
    for ( const auto& g : groups )
    {
        switch ( g.element )
        {
        case ObjElement::Vertex:
            numPoints += ( g.end - g.begin );
            if ( !colorChecked )
            {
                colorChecked = true;
                constexpr Vector3d cInvalidColor = { -1., -1., -1. };
                Vector3d v;
                Vector3d c{ cInvalidColor };
                std::string_view line( data + newlines[g.begin], newlines[g.begin + 1] - newlines[g.begin] );
                auto res = parseObjCoordinate( line, v, &c );
                if ( !res.has_value() )
                    return unexpected( res.error() );
                hasColors = c != cInvalidColor;
            }
            break;
        case ObjElement::TextureVertex:
            numUVs += ( g.end - g.begin );
            break;
        case ObjElement::Face:
            numFaces += ( g.end - g.begin );
            break;
        case ObjElement::MaterialLibrary:
        {
            std::string_view line( data + newlines[g.begin], newlines[g.end] - newlines[g.begin] );
            // TODO: support multiple files
            std::string filename( line.substr( strlen( "mtllib" ), std::string_view::npos ) );
            boost::trim( filename );