message: fix crash when some materials don't compute the bsdf frame
diff: @@ -40,8 +40,8 @@ inline void updateAuxilliaryData(
  sample.normal = make_vec3f(0.f);
  } else if (pathVertex.type == SURFACE) {
  vec3f Ns = pathVertex.dg.Ns;
  - foreach_unique (f in pathVertex.bsdf)
  - if (f != NULL) {
  + foreach_unique (f in pathVertex.bsdf) {
  + if (f != NULL && f->frame != NULL)
  Ns = getN(f);
  }
  sample.normal = Ns;
  