std::ostringstream oss;
oss << "phm2if: nx=" << opt_nx << ", ny=" << opt_ny << ", viewRatio=" << optViewRatio << ", nsample=" << opt_nsample << ", ";
std::ostringstream oss;
oss << "phm2if: nx=" << opt_nx << ", ny=" << opt_ny << ", viewRatio=" << optViewRatio << ", nsample=" << opt_nsample << ", ";