The
Application Programming Interface (API) is the way in which you, as the programmer, instruct the engine, and so the PC, what to do. All of UE4's functionality is encapsulated into modules, including very basic and core functionality. Each module has an API for it. To use an API, there is a very important linkage step, where you must list all APIs that you will be using in your build in a ProjectName.Build.cs
file, which is located in your Solution Explorer window.
There are a variety of APIs inside the UE4 engine that expose functionality to various essential parts of it. Some of the interesting APIs that we'll explore in this chapter are as follows:
Core/Logging API – Defining a custom log category
Core/Logging API –
FMessageLog
to write messages to the Message LogCore/Math API – Rotation using
FRotator
Core/Math API – Rotation using
FQuat
Core/Math API – Rotation...