Unreal Engine C++ Pro

Unreal Engine C++ Pro

This skill provides expert-level guidelines for developing with Unreal Engine 5 using C++. It focuses on writing robust, performant, and standard-compliant code.

When to Use

Use this skill when:

• Developing C++ code for Unreal Engine 5.x projects
• Writing Actors, Components, or UObject-derived classes
• Optimizing performance-critical code in Unreal Engine
• Debugging memory leaks or garbage collection issues
• Implementing Blueprint-exposed functionality
• Following Epic Games' coding standards and conventions
• Working with Unreal's reflection system (UCLASS, USTRUCT, UFUNCTION)
• Managing asset loading and soft references

Do not use this skill when:

• Working with Blueprint-only projects (no C++ code)
• Developing for Unreal Engine versions prior to 5.x
• Working on non-Unreal game engines
• The task is unrelated to Unreal Engine development

Core Principles

1. UObject & Garbage Collection:

   • Always use UPROPERTY() for UObject* member variables to ensure they are tracked by the Garbage Collector (GC).
   • Use TStrongObjectPtr<> if you need to keep a root reference outside of a UObject graph, but prefer addToRoot() generally.
   • Understand the IsValid() check vs nullptr. IsValid() handles pending kill state safely.

2. Unreal Reflection System:

   • Use UCLASS(), USTRUCT(), UENUM(), UFUNCTION() to expose types to the reflection system and Blueprints.
   • Minimize BlueprintReadWrite when possible; prefer BlueprintReadOnly for state that shouldn't be trampled by logic in UI/Level BPs.

3. Performance First:

   • Tick: Disable Ticking (bCanEverTick = false) by default. Only enable it if absolutely necessary. Prefer timers (GetWorldTimerManager()) or event-driven logic.
   • Casting: Avoid Cast<T>() in hot loops. Cache references in BeginPlay.
   • Structs vs Classes: Use F structs for data-heavy, non-UObject types to reduce overhead.

Naming Conventions (Strict)

Follow Epic Games' coding standard: