mrsutivu/unreal-engine-5-c-expert-skills

📖 Overview

Welcome to the Unreal Engine 5 C++ Expert Skills Library.

This repository contains nearly 100 hyper-specialized Markdown files (SKILL.md) designed to act as the ultimate architectural and technical brain for AI Agents (like Claude, Gemini, Antigravity) and human developers.

Unlike standard tutorials, these skills are written as strict operational protocols. They are optimized for AI ingestion (using the “Caveman Lite” linguistic format) to drastically reduce token consumption while maximizing technical density.

🛡️ The “Zero Hallucination” Philosophy

Every file in this repository is designed to prevent AI coding errors:

• BAD vs GOOD Snippets: Explicitly shows what not to do (e.g., using Cast in a Tick loop) vs the standard (e.g., using IsA()).
• Verification Checklists: Each skill ends with a binary checklist for the Agent to self-verify its code before pushing a PR.
• Safety First: Deep focus on pointers (TWeakObjectPtr), memory leaks, and Network Authority (HasAuthority()) to prevent silent crashes in multiplayer environments.

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🗂️ The 10 Architectural Pillars

This library covers the entire spectrum of game development in UE5, from basic setup to low-level engine hacking.

1. 🏗️ Core C++ & Memory Management

• The migration to TObjectPtr.
• Native Smart Pointers (TSharedRef, TUniquePtr) vs std::.
• High-performance memory stacks (FMemStack, FInstancedStruct).

2. ⚡ Performance & Optimization

• Eradicating the Tick function (Event-Driven architecture).
• CPU Cache Locality and Struct Padding optimization.
• Object Pooling for rapid-fire actors.
• Math & String optimization (FStringBuilderBase, DistSquared).

3. 🌐 Multiplayer & Network Replication

• AGameMode vs AGameState responsibilities.
• The Push Model (MARK_PROPERTY_DIRTY_FROM_NAME) for massive CPU savings.
• FFastArraySerializer for large inventory replication.
• Safe RPC implementation and RepNotify state synchronization.

4. ⚔️ Gameplay Ability System (GAS)

• UAttributeSet clamping and ATTRIBUTE_ACCESSORS.
• Instancing policies for UGameplayAbility.
• UGameplayEffectExecutionCalculation for complex damage math.
• Synchronizing targeting info via FGameplayAbilityTargetData.

5. 🧠 Artificial Intelligence (Mass Entity & BTs)

• C++ Behavior Tree Tasks (UBTTaskNode), Services, and Decorators.
• FBlackboardKeySelector for safe memory access.
• Mass Entity (ECS) architecture for 100,000+ simulated entities.
• The new State Trees hybrid system.

6. 🏃 Animation & Physics

• UE5’s NativeThreadSafeUpdateAnimation for multi-threaded crowds.
• Executing AnimMontage and AnimNotifies from C++.
• Advanced Raycasts (SweepMulti, FCollisionQueryParams).
• Safely extracting Physical Materials for surface-specific VFX.

7. 🎮 Gameplay Systems & Blueprint Interop

• BlueprintNativeEvent vs BlueprintImplementableEvent.
• C++ Interfaces (Execute_).
• Enhanced Input System (InputMappingContext) in UE 5.1+.
• Native FGameplayTag integration.

8. 🖌️ UI Development (Slate & UMG)

• Pure native C++ UI via Slate (SNew, TAttribute).
• Invalidation Boxes for 120+ FPS UMG widgets.
• Virtualized lists (SListView / STileView).
• Proper NativeDestruct garbage collection to prevent Zombie UI.

9. 🖥️ Shaders, Rendering & RDG

• Writing HLSL in usf/ush files.
• Building passes with the Render Dependency Graph (FRDGBuilder).
• Compute Shaders and UAV manipulation.
• Modifying the UE5 Tonemapper and reading G-Buffer data.

10. 🛠️ Editor Tooling & Distribution

• Extending the Editor via IDetailCustomization and FAssetTypeActions_Base.
• Creating custom Blueprint Nodes (UK2Node).
• Passing Fab Marketplace submission requirements (HAL, cross-platform safety).

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📂 The references/ Directory (Memory Dumps)

While standard skills are fast and concise, the references/ folder contains complete, copy-pasteable C++ boilerplate templates for Unreal’s most complex “Final Boss” systems:

• rdg-pipeline-template.md: Complete Compute/Pixel Shader setup.
• gas-attribute-execution.md: Boilerplate for AttributeSets and ExecCalcs.
• async-multithreading-tasks.md: Syntax for UE::Tasks, AsyncTask, and UE5Coro.
• multiplayer-seamless-travel-code.md: Data persistence via CopyProperties.
• slate-ui-macro-lexicon.md: Deep dive into SAssignNew and Slate bindings.

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🤖 How to Use (For AI Agents)

1. Ingest the Context: When a user assigns you a task (e.g., “Create a multiplayer gun”), scan the SKILL.md files related to your task (e.g., rpc-server-client-multicast.md, raycast-line-trace.md).
2. Follow the Rules: Treat the instructions as absolute Engine Law. Never assume an API implementation without checking the skill.
3. Verify: Before outputting code, run through the Verification Checklist at the bottom of each skill.

👨‍💻 How to Use (For Humans)

Read these files as a quick-reference “Senior Dev Cheat Sheet”. If you forget the exact syntax for a DOREPLIFETIME_CONDITION or a DECLARE_GLOBAL_SHADER, you will find the most modern, optimized UE 5.4+ approach documented here without the fluff of a 30-minute tutorial.

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