#pragma once #include namespace internal { // local: a sphere with center at (0, 0, 0) and radius 1 // u: planar angle from x-axis to z-axis // v: polar angle from xz-plane to y-axis struct sphere_face_t final : subface { }; } // namespace internal namespace detail { template <> struct hasher { size_t operator()(const internal::sphere_face_t &subface) const { return hash_funcs(subface.local_to_world); } }; } // namespace detail