[MOAB-dev] ray_intersect_sets function

[hongjun at mcs.anl.gov]

Hi! All

I have a question about ray tracing function,

MBOrientedBoxTreeTool::ray_intersect_sets( 
                                    std::vector<double>& distances_out,
                                    std::vector<MBEntityHandle>& sets_out,
                                    std::vector<MBEntityHandle>& facets_out,
                                    MBEntityHandle root_set,
                                    double tolerance,
                                    unsigned min_tolerace_intersections,
                                    const double ray_point[3],
                                    const double unit_ray_dir[3],
                                    const double* ray_length, 
                                    TrvStats* accum );

When I use this function, it just returns one intersection distance/set/facet for sphere or curved surfaces.
Is it a bug or is it intended?
Otherwise, am I using incorrectly?

Could any body give me some advices for me?
Thanks.

Hong-Jun