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I recently put together a demo project that shows how to create fully interactive AI NPCs in Unreal Engine using speech recognition, AI chatbots, text-to-speech, and realistic lip synchronization. The entire system is built with Blueprints and works across Windows, Linux, Mac, iOS, and Android. If you’ve been exploring AI NPC solutions like ConvAI or Charisma.ai, you’ve probably noticed the tradeoffs: metered API costs that scale with your player count, latency from network roundtrips, and dependency on cloud infrastructure. This modular approach gives you more control, run components locally or pick your own cloud providers, avoid per-conversation billing, and keep your players interactions private if needed. You own the pipeline, so you can optimize for what actually matters to your game. Plus, with local inference and direct audio-based lip sync, you can achieve lower latency and more realistic facial animation, check the demo video below to see the difference yourself. ...

Introduction Still, as of UE 5.5, multi-line editable text boxes lack proper keyboard and gamepad navigation support. Let’s fix this without modifying the engine’s source code. I’ll experiment with a simple 2x2 grid of text boxes to demonstrate how we can implement smooth, unified navigation across both keyboard and gamepad input devices, which you can also recreate for testing purposes. Current Limitations Keyboard Arrow keys only allow navigation within the content of a single text box, and there’s no way to navigate between text boxes themselves. ...

Chunk downloading is a technique used to retrieve large binary data from the server in separate parts, ensuring reliability and compatibility across different platforms. Unreal Engine’s HTTP module has a limitation of 2GB for binary HTTP response content due to internal restrictions (specifically, TArray<uint8> uses the int32 size type, which has a maximum value of 2,147,483,647, approximately 2 GB in our case). To overcome this limitation, we can use the Range HTTP header supported by most servers, without requiring any file preparation or segmentation. ...

Unreal Engine has an alternative implementation of std::mutex called FCriticalSection which makes it possible for your data to be safely accessed from different threads, preventing race conditions. This takes the same approach, handling it with one thread locking until the other thread completes the necessary operations. There are two ways to handle lock/unlock logic. The first is low-level, which is used to directly lock and unlock threads. Use with caution due to possible deadlocks . Just use FCriticalSection::Lock and FCriticalSection::Unlock functions where needed to follow this way. ...

This article addresses the question of how to work with UObjects in a thread-safe way when dealing with workers, async tasks, thread pools, or whatever else using a non-game thread. One critical issue to address is the handling of garbage collection. When passing an UObject, which is not set to root, directly to a background thread, there’s a risk that the garbage collector may silently delete the passed UObject. Even frequent validity checks of the UObject (e.g. IsValidLowLevel()) on a background thread cannot guarantee the object’s survival even moments after the check. ...