Unreal Engine Reflection System

Information for programmers developing Objects to be used with Unreal Engine.

Choose your operating system:

Windows

macOS

Linux

Unreal Engine provides two toolsets for programmers which can also be used in tandem to accelerate development workflows. New gameplay classes, Slate and Canvas user interface elements, and editor functionality can be written with C++, and all changes will be reflected in Unreal Editor after compiling with either Visual Studio or XCode. The Blueprint visual scripting system is a robust tool which enables classes to be created in-editor through wiring together function blocks and property references.

C++ classes can be used as a base for Blueprint classes, and in this way programmers can set up fundamental gameplay classes that are then sub-classed and iterated on by level designers.

Getting Started

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Programming Quick Start

Create your first code project and add a new C++ class.

Create your first code project and add a new C++ class.

Development Setup

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Compiling Game Projects

Compiling individual game projects using Visual Studio on Windows, or Xcode on Mac.

Compiling individual game projects using Visual Studio on Windows, or Xcode on Mac.

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Downloading Unreal Engine Source Code

Steps for connecting to the source code repository and downloading the latest build of Unreal Engine.

Steps for connecting to the source code repository and downloading the latest build of Unreal Engine.

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Updating to the Latest Changes from Epic

Describes how to update your fork of the Unreal Engine source code to get the latest fixes and new features.

Describes how to update your fork of the Unreal Engine source code to get the latest fixes and new features.

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Contributing to Unreal Engine

Describes how to use the GitHub Pull Request mechanism to submit changes you've made to the Unreal Engine source back to Epic.

Describes how to use the GitHub Pull Request mechanism to submit changes you've made to the Unreal Engine source back to Epic.

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Writing Code Snippets

A specification for writing code snippets for the Unreal Engine API reference manual.

A specification for writing code snippets for the Unreal Engine API reference manual.

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Live Coding

Recompile and patch your game's binaries at runtime.

Recompile and patch your game's binaries at runtime.

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Managing Game Code

Adding code and generating project files.

Adding code and generating project files.

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C++ Class Wizard

An overview of the C++ Class Wizard in Unreal Engine.

An overview of the C++ Class Wizard in Unreal Engine.

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Programming Tools

Applications, tools, and add-ins that are useful for programmers working with Unreal Engine.

Applications, tools, and add-ins that are useful for programmers working with Unreal Engine.

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Low-Level Memory Tracker

Going over how to use the Low-Level Memory Tracker in your Unreal Engine projects.

Going over how to use the Low-Level Memory Tracker in your Unreal Engine projects.

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Sparse Class Data

The Sparse Class Data system eliminates wasted memory from redundant properties.

The Sparse Class Data system eliminates wasted memory from redundant properties.

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Setting Up Visual Studio

Tips, tricks, and techniques for setting up Visual Studio to work with Unreal Engine

Tips, tricks, and techniques for setting up Visual Studio to work with Unreal Engine

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UnrealVS Extension

Guide for installing, setting up, and using the UnrealVS extension for Visual Studio.

Guide for installing, setting up, and using the UnrealVS extension for Visual Studio.

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Visual Studio Tips and Tricks

Useful tips and tricks for working on UE content in Visual Studio

Useful tips and tricks for working on UE content in Visual Studio

Unreal Engine Architecture

Whether you are programming with C++, Blueprints, or a combination of the two, the underlying Unreal Engine architecture is the same.

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Asserts

Reference for Unreal Engine's Assert Functionality

Reference for Unreal Engine's Assert Functionality

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Gameplay Classes

Reference for creating and implementing gameplay classes.

Reference for creating and implementing gameplay classes.

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UFunctions

Reference for creating and implementing functions for gameplay Classes

Reference for creating and implementing functions for gameplay Classes

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Gameplay Modules

Collections of gameplay classes belonging to a game project compiled into DLLs.

Collections of gameplay classes belonging to a game project compiled into DLLs.

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Interfaces

Reference to creating and implementing interfaces.

Reference to creating and implementing interfaces.

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Metadata Specifiers

Metadata keywords used when declaring UClasses, UFunctions, UProperties, UEnums, and UInterfaces to specify how they behave with various aspects of Unreal Engine and the editor

Metadata keywords used when declaring UClasses, UFunctions, UProperties, UEnums, and UInterfaces to specify how they behave with various aspects of Unreal Engine and the editor

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Properties

Reference for creating and implementing properties for gameplay classes.

Reference for creating and implementing properties for gameplay classes.

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Structs

Reference to creating and implementing structs for gameplay classes.

Reference to creating and implementing structs for gameplay classes.

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C++ Programming Tutorials

Step-by-step instructional guides for hands-on learning of programming in Unreal Engine.

Step-by-step instructional guides for hands-on learning of programming in Unreal Engine.

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Referencing Actors

A How To Guide for Referencing Actors in Unreal Engine.

A How To Guide for Referencing Actors in Unreal Engine.

Gameplay Architecture

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Asynchronous Asset Loading

Methods for loading and unloading assets during runtime.

Methods for loading and unloading assets during runtime.

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Command-Line Arguments

A collection of arguments that can be passed to the engine's executable to configure options controlling how it runs.

A collection of arguments that can be passed to the engine's executable to configure options controlling how it runs.

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Core Redirects

Core Redirects enable remapping classes, enums, functions, packages, properties, and structs at load time.

Core Redirects enable remapping classes, enums, functions, packages, properties, and structs at load time.

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Data Validation

Developers can extend this system to validate assets with custom-scripted rulesets.

Developers can extend this system to validate assets with custom-scripted rulesets.

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Unreal Engine Modules

Modules are the building blocks of Unreal Engine's software architecture. You can organize your code into modules to create more efficient and maintainable projects.

Modules are the building blocks of Unreal Engine's software architecture. You can organize your code into modules to create more efficient and maintainable projects.

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Referencing Assets

Control how an asset is referenced and loaded into memory.

Control how an asset is referenced and loaded into memory.

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Asset Registry

How assets are discovered by the editor and how to make it know more about asset types before they are loaded.

How assets are discovered by the editor and how to make it know more about asset types before they are loaded.

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String Handling

An overview of the string classes available in Unreal with reference guides for FName, FText, and FString.

An overview of the string classes available in Unreal with reference guides for FName, FText, and FString.

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Tasks System

An Overview of the Tasks System.

An Overview of the Tasks System.

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Unreal Smart Pointer Library

Custom implementation of shared pointers, including weak pointers and non-nullable shared references.

Custom implementation of shared pointers, including weak pointers and non-nullable shared references.

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Versioning of Assets and Packages

Using customized serialization code and versioning to control how Objects are loaded from Assets and Packages.

Using customized serialization code and versioning to control how Objects are loaded from Assets and Packages.

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UObject Instance Creation

Methods of creating new instances of Objects in gameplay code.

Methods of creating new instances of Objects in gameplay code.

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Unreal Object Handling

Overview of the features of the UObject system.

Overview of the features of the UObject system.

Gameplay Guides

Unreal Engine API Reference

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Unreal Engine C++ API Reference

System Guides

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Animation Node Technical Guide

Guide to creating new nodes for use within graphs in Anim Blueprints.

Guide to creating new nodes for use within graphs in Anim Blueprints.

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Automation System Overview

Overview of the automation system used for unit testing, feature testing, and content stress testing.

Overview of the automation system used for unit testing, feature testing, and content stress testing.

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Blueprints Technical Guide

Technical guide for programmers working with Blueprints.

Technical guide for programmers working with Blueprints.

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Online Subsystems and Services

Learn how to use online subsystems and services in Unreal Engine, including Epic Online Services.

Learn how to use online subsystems and services in Unreal Engine, including Epic Online Services.

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Online Subsystem Steam

An overview of Online Subsystem Steam, including how to set up your project for distribution on Valve's Steam platform.

An overview of Online Subsystem Steam, including how to set up your project for distribution on Valve's Steam platform.

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Graphics Programming

Information for graphics programmers working with the rendering systems and writing shaders.

Information for graphics programmers working with the rendering systems and writing shaders.

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Slate UI Programming

Program user interfaces with Unreal Engine's Slate framework.

Program user interfaces with Unreal Engine's Slate framework.

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Unreal Build Pipeline

Reference material for Unreal Engine's build pipeline

Reference material for Unreal Engine's build pipeline

Automated Builds

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BuildGraph Script Conditions

Learn syntax to write BuildGraph script conditions.

Learn syntax to write BuildGraph script conditions.

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BuildGraph Script Elements

Learn about BuildGraph Elements.

Learn about BuildGraph Elements.

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BuildGraph Script Types

Learn about valid data types for BuildGraph attributes.

Learn about valid data types for BuildGraph attributes.

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BuildGraph

Customize your builds with the BuildGraph scripting system.

Customize your builds with the BuildGraph scripting system.

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BuildGraph Usage

This page provides sample BuildGraph Script usage.

This page provides sample BuildGraph Script usage.

Asset Handling Reference Guides

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Asynchronous Asset Loading

Methods for loading and unloading assets during runtime.

Methods for loading and unloading assets during runtime.

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Asset Registry

How assets are discovered by the editor and how to make it know more about asset types before they are loaded.

How assets are discovered by the editor and how to make it know more about asset types before they are loaded.

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Data Validation

Developers can extend this system to validate assets with custom-scripted rulesets.

Developers can extend this system to validate assets with custom-scripted rulesets.