Why Interfaces in Unreal C++ are so important

hello there are you interested in utilizing interfaces in your unreal game but feel uncertain about how and when to apply them let's explore this topic in this video interfaces essentially are a collection of functions that classes must Implement if they choose to adopt the interface think of an interface as a contract it specifies functions and any class that wishes to implement the interface must fulfill this contract by incorporating these functions this is particularly handy when you aim to offer functionality to classes that may be developed in the future consider your inventory system for example it could employ interfaces to hold pointers to items such an interface might be termed I item this approach allows the use of any class or even multiple classes for your items as long as the item adheres to your interface if you plan to use your inventory system in a future game you can easily do so since it isn't hardcoded to a specific item class now let's delve into C++ example in C++ there is no explicit keyword for an interface instead we use multiple inheritance so we actually create a class with purely virtual functions to Define an interface suppose our character can take damage we could create an interface named I damageable with functions like get current health and apply damage these functions are purely virtual this means it isn't implemented on the interface site but instead on the C++ class set inherit the interface however to use your interface with unre engine blueprints you must declare also an additional class that signals to Unreal that an interface exists the U interface specifier serves precisely this purpose unfortunately blueprints can't Implement purely virtual functions directly to integrate interfaces in blueprints you must use blueprint implementable event or blueprint native event functions you can check out my previous videos to see how to implement these events returning to our C++ interface let's see how to implement it for your character simply inherit the interface and overwrite the virtual function and there you have it when you need to use the interface function you just need to verify the actor class implements the interface by casting to it and checking for a null pointer if it's not an outp pointer the interface is in place and you can invoke any of its functions by the way there are also other ways to check if an object implements an interface you can also use the implements function for U objects or the implements interface function for you classes but casting directly to the interface and just checking for a n pointer is my prefer way as usually you need to cast any way to access the functions behind the interface that concludes already the tutorial I hope it has clarified how to use interfaces in C++ uh join me in the next video where we'll delve further into basic unre C++ tutorials and see you then

Channel: Scripted Adventure

Views: 6,065

Keywords: unreal engine, gamedev, ue5, c++, cpp, cplusplus, blueprints, interfaces, programming

Id: WoPt-Ucy_zI

Length: 3min 17sec (197 seconds)

Published: Tue Mar 05 2024