What is this principle？

[LiXiaoRan]

What is this principle？ How does JS execute unreal logic？C++ is base？

[getnamo]

Uses Unreal reflection system to expose nearly whole C++/blueprint API to Javascript. The Javascript is running on an embedded V8 instance (C++ lib). V8 is incredibly fast, around 100x faster than blueprint in tight loops (unless nativized).