Method sah

tutorials/bvh_builder/bvh_builder_device.cpp:79–81

      : id(id), bounds(bounds) {}

    float sah() {
      return 1.0f;
    }

    static void* create (RTCThreadLocalAllocator alloc, const RTCBuildPrimitive* prims, size_t numPrims, void* userPtr)
    {