Game Development Patterns with Unreal Engine 5: Build maintainable and scalable systems with C++ and Blueprint

Cover....1

Title page....2

Copyright and credits....3

Dedication....4

Foreword....5

Contributors....6

Table of Contents....8

Preface....12

Part 1: Learning from Unreal Engine 5....18

Chapter 1: Understanding Unreal Engine 5 and its Layers....20

Technical requirements....20

Introducing Unreal Engine 5....21

Installing Unreal Engine 5 and preparing your development environment....22

The Fuzzy layer – bridging the gap from C to Blueprint....25

Property Specifiers....27

Function Specifiers....28

Useful inheritance....28

Translating back from Blueprint to C....30

Worked example....32

Summary....35

Questions....35

Answers....36

Chapter 2: Hello Patterns....38

Technical requirements....38

S.O.L.I.D. principles....39

Single responsibility....40

Open-closed....40

Liskov substitution....42

Interface segregation....44

Dependency inversion....46

Exploring solutions to common problems....47

The moving box problem....48

The rotating box problem....56

The cascading cast chain problem....59

The trade-off....63

Summary....64

Chapter 3: UE5 Patterns in Action – Double Buffer, Flyweight, and Spatial Partitioning....66

Technical requirements....66

Double buffer....67

Flyweight....70

Spatial partitioning....72

Introducing World Partition....74

Understanding when objects are loaded....78

Ensuring actors are loaded when required....80

Enabling World Partition on an existing level....82

Summary....82

Chapter 4: Premade Patterns in UE5 – Component, Update Method, and Behavior Tree....84

Technical requirements....84

Understanding and creating components....85

Applying the update method for prototyping gameplay....91

Working with behavior trees....93

Creating the AI controller....95

Creating the Blackboard asset....97

Building the behavior tree....98

Summary....113

Part 2: Anonymous Modular Design....114

Chapter 5: Forgetting Tick....116

Technical requirements....116

Before we begin....117

A world that ticks....117

A clock that stops....120

Event driven systems....125

Summary....128

Chapter 6: Clean Communication – Interface and Event Observer Patterns....130

Technical requirements....130

Interfacing communication across classes in UE5....131

Blueprint interfaces....131

Interface events versus functions....135

Interfaces in C....137

Building an example interface communication....139

Implementing event delegate communication across UE5....140

Event delegates in Blueprint....140

Event delegates in C....144

Building a useful delegate tool....146

Summary....149

Chapter 7: A Perfectly Decoupled System....150

Technical requirements....150

Using UML to plan a sample hierarchy....151

What are the types of class relations?....151

What is a sequence diagram?....153

Decoupling the reference train....154

Modularity and decoupling....154

Establishing infrastructure....157

Implementing decoupled design in an example....158

Benefits of decoupling....169

Summary....169

Part 3: Building on Top of Unreal....170

Chapter 8: Building Design Patterns – Singleton, Command, and State....172

Technical requirements....172

Implementing a Singleton pattern – understanding why its a Pandoras box....173

Implementing the Command pattern for different use cases....175

Command pattern for undo functionality in Blueprint Utilities....177

Command pattern for gameplay in C....180

Creating the many levels of a state machine....183

Exploring animation state machines....184

Enumswitch implementation....186

Static versus instanced states....188

Concurrent state machines....190

Hierarchical state machines....191

Pushdown automata....192

Summary....193

Chapter 9: Structuring Code with Behavioral Patterns –Template, Subclass Sandbox, and Type Object....194

Technical requirements....195

Exploring the template pattern....195

Building the template (parent class)....196

Creating child classes....198

Template pistol....200

Template shotgun....205

Understanding subclass sandbox....206

Building the sandbox (parent class)....207

Creating child classes....210

Sandbox pistol....210

Sandbox shotgun....213

Type object pattern....214

Variants....215

Data Tables....217

Data Assets....217

Summary....221

Chapter 10: Optimization through Patterns....222

Technical requirements....223

Using dirty flags to reduce unnecessary processing....223

Application of dirty flags....224

How data locality affects code efficiency....225

Hotcold splitting....226

Contiguous arrays....226

Object pooling our resources to save time later....227

Implementing object pooling....228

Making an object pool....229

Summary....241

Index....242

Other Books You May Enjoy....249

Improve your game's code with design patterns to make it more readable, reusable, modular, and optimized, guided by an Unreal Authorized Instructor to enhance your overall use of C++ with Unreal Engine

Key Features

• Explore programming patterns, structures, and principles and their applications in Unreal Engine 5 game development
• Translate code from Blueprint to C++ to implement performant solutions in game development
• Build a decoupled communications hierarchy and become a better game developer
• Purchase of the print or Kindle book includes a free PDF eBook

Book Description

Design patterns serve as a toolkit of techniques and practices that enable you to write code that’s not only faster, but also more manageable. With this book, you’ll explore a range of design patterns and learn how to apply them to projects developed in Unreal Engine 5.

You’ll begin by delving into the foundational principles of coding and develop a solid understanding of the concepts, challenges, and benefits of using patterns in your code. As you progress, you’ll identify patterns that are woven into the core of Unreal Engine 5 such as Double Buffer, Flyweight, and Spatial Partitioning, followed by some of the existing tool sets that embody patterns in their design and usage including Component, Behavior Tree, and Update.

In the next section of the book, you’ll start developing a series of gameplay use cases in C++ to implement a variety of design patterns such as Interface and Event-based Observers to build a decoupled communications hierarchy. You’ll also work with Singleton, Command, and State, along with Behavioral Patterns, Template, Subclass Sandbox, and Type Object. The final section focuses on using design patterns for optimization, covering Dirty Flag, Data Locality, and Object Pooling.

By the end, you’ll be proficient in designing systems with the perfect C++/Blueprint blend for maintainable and scalable systems.

What you will learn

• Grasp the essence of design patterns and their inherent utility
• Understand the layers within UE 5 and how they work together
• Identify the relationship between C++ code and Blueprint in Unreal Engine 5
• Recognize the design patterns found within existing Unreal Engine 5 functions
• Explore design patterns to understand their purpose and application within Unreal Engine 5
• Creatively apply design patterns to existing code to overcome common challenges

Who this book is for

If you are a beginner or intermediate game developer working with Unreal Engine and looking to improve your C++ coding practices, this book is tailor-made to help you produce clean, reusable code through the application of design patterns.

While this book will cover introductory tasks to show the fundamentals of Unreal Engine 5, its primary purpose is not to teach Unreal Engine from scratch. Prior experience with Unreal Engine will be beneficial, but don’t fret if your knowledge isn’t in-depth; the book will introduce tools and features as needed.