message: use something other than garbage values for ray.Ng in implicit isosurfaces
diff: @@ -93,8 +93,12 @@ void Isosurfaces_intersect_kernel(const RTCIntersectFunctionNArguments *uniform
  ray->geomID = self->super.geomID;
  ray->primID = tmpRay.primID;
  ray->t = tmpRay.t;
  - ray->Ng = tmpRay.Ng;
  ray->u = tmpRay.u; // transport epsilon to postIntersect
  +
  + // NOTE(jda) - Initialize ray.Ng with something, even if it's wrong
  + // (better than garbage). Real normals are computed if DG_NS
  + // flag is specified to postIntersect()
  + ray->Ng = negate(ray->dir);
  }
  }
  }
  