public static extern SU_RESULT SUPolyline3dCreate(ref SUPolyline3dRef polyline);
public static extern SU_RESULT SUPolyline3dRelease(ref SUPolyline3dRef polyline);
public static extern SUDrawingElementRef SUPolyline3dToDrawingElement(SUPolyline3dRef line);
public static extern SUEntityRef SUPolyline3dToEntity(SUPolyline3dRef line);
public static extern SU_RESULT SUPolyline3dGetPoints(SUPolyline3dRef line, size_t len, SUPoint3D[] points, ref size_t count);
public static extern SU_RESULT SUPolyline3dGetNumPoints(SUPolyline3dRef line, ref size_t count);
public static extern SU_RESULT SUPolyline3dAddPoints(SUPolyline3dRef polyline, size_t num_points, ref SUPoint3D[] points);