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Unreal Engine
Let's talk about Unreal Engine. After all, this is a book about how to develop game AI within this wonderful game engine.
Unreal Engine is a game engine that was developed by Epic Games. It was first released in 1998, and nowadays it is one of the most used (open) game engines (alongside Unity) due to its powerful features. The following screenshot shows the main interface of Unreal Engine:
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We need to have the latest version of Unreal Engine installed. You can find it by visiting https://www.unrealengine.com/en-US/what-is-unreal-engine-4 . Unless you took Unreal Engine from the source code (https://docs.unrealengine.com/en-us/Programming/Development/BuildingUnrealEngine), you will have the Epic Launcher installed. If you are a Blueprint user, and do not intend to use C++, then this is enough for you. If, on the other hand, you will be using C++, you will need to perform a couple of extra steps.
When installing the Engine, you will need to check some options (if you are using C++). In particular, we need to check that we have both "Engine Source" and "Editor symbols for debugging", as shown in the following screenshot:
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By doing so, we will be able to navigate through the C++ Engine Source and also have a full stack of calls in the case of a crash (so you will know what went wrong).