Unreal Engine 4 AI Programming Essentials

Peter L. Newton, Jie Feng

• Publisher: Packt Publishing
• Year: 2016
• eBook ISBN: 9781784393120
• Edition: 1
• Topic: Computer Science
• Subtopic: Programming Games
• Index: Computer Science

Create responsive and intelligent game AI using Blueprints in Unreal Engine 4

About This Book

• Understand and apply your Game AI better through various projects such as adding randomness and probability, and introducing movement
• Configure and debug Game AI logic using multiple methodologies
• Bridge the gap between your knowledge and Game AI in Unreal Engine 4

Who This Book Is For

This book is for programmers and artists who want to expand their knowledge of Game AI in relation to Unreal Engine 4. You are recommended to have some experience of exploring Unreal Engine 4 prior to this book because we jump straight into Game AI.

What You Will Learn

• Understand the fundamental components of Game AI within Unreal Engine 4
• Skillfully introduce Game AI within Unreal Engine 4
• Configure, customize, and assign Navigation and AI components to your pawn
• Create, debug, and analyze Game AI behavior
• Design responsive Game AI using the Behavior Tree methodology
• Create smart objects designed to interact with AI
• Utilize advanced AI features within your project to maximize the user experience

In Detail

Unreal Engine is a powerful game development engine that provides rich functionalities to create 2D and 3D games. Developers have the opportunity to build cross-platform mobile and desktop games from scratch. This book will show you how to apply artificial intelligence (AI) techniques to your Unreal project using blueprints as your scripting language. You will start with an introduction to AI, and learn how it is applied to gaming. Then you'll jump right in and create a simple AI bot and apply basic behaviors to allow it to move randomly. As you progress, you'll find out how to implement randomness and probability traits. Using NavMesh, you will impart navigation components such as character movement, MoveTo nodes, settings, and world objects, and implement Behavior Trees. At the end of the book, you will troubleshoot any issues that might crop up while building the game.

Style and approach

This easy-to-follow project-based guide throws you directly into the excitement of Game AI in an approachable and comprehensive manner.

Unreal Engine 4 AI Programming Essentials

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Table of Contents

Unreal Engine 4 AI Programming Essentials

Credits

About the Authors

About the Reviewer

www.PacktPub.com

eBooks, discount offers, and more

Why subscribe?

Preface

What this book covers

What you need for this book

Who this book is for

Conventions

Reader feedback

Customer support

Downloading the example code

Downloading the color images of this book

Errata

Piracy

Questions

1. Introduction to Game AI

Game Artificial Intelligence

How AI affects the gaming experience

Techniques and practices of game AI

Navigation

Achieving realistic movement with Steering

Creating a character with randomness and probability

Creating complex decision making with Behavior Tree

Root

Decorators

Composites

Services

Tasks

Blackboard

Sensory systems

Machine learning

Tracing

Influence Mapping

Unreal Engine 4 tools

Summary

2. Creating Basic AI

Goal

Setting up the project

Environment

Prerequisites

Using our new AIController class

Assigning the AIController class

Placing the pawn

Sending the instructions

Small tips on MoveToLocation

Reviewing the current progress

Adding the challenge

Traces

Reviewing the current progress

The Enemy logic

Adding the Enemy AI

Summary

3. Adding Randomness and Probability

Introducing probability

Probabilistic distribution

Non-uniform distribution

RandomStream in Unreal Engine 4

The plan

Adding Wander

Setting up the project

Creating probability

Non-uniform distribution with RandomStream

Creating transitions

Fleeing and attacking

Back to the action

The results!

Summary

4. Introducing Movement

Overview

Path Finding

The A* algorithm

Navigation Mesh

RecastNavMesh

The movement component

The AIController

Let's start!

Waypoints

Navigation

Navigation Modifiers

Back in the editor

The NavArea class

The navigation cost

Summary

5. Giving AI Choices

Behavior Tree in AIController

Creating Behavior Tree

Blackboard

Designing Behavior Tree

The Behavior Tree service

State transitions

Blackboard Compare Decorator

Environment Query System

Summary

6. How Does Our AI Sense?

Overview

AI Sense

AI Perception components

State machines

Pawn detection

State transition

Resetting the state

Simulating and playing

Summary

7. More Advanced Movement

Setting up the agents

Viewing the agent

Following the agent

Follow or lead

Steering behavior: Flocking

Flocking agents

Controlling behavior through UMG

A simple UI

Summary

8. Creating Patrol, Chase, and Attack AI

Creating a Blackboard

Mid-range attack

Controllers

Waypoints

BT Composites, Task, Decorator, and Service

Creating the logic

Summary

9. What Have We Learned?

Creating basic AI

The pros and cons of using controls

Adding randomness and probability

The pros and cons of using randomness

The pros and cons of using probability

Introducing movement

Giving our AI choice

The pros and cons of using EQS

The pros and cons of using Blueprint

How does our AI sense?

More advanced movement

Creating patrol, chase, and attack AI

The pros and cons of using Behavior Tree

The pros and cons of using blueprint for AI

Summary

Index

Unreal Engine 4 AI Programming Essentials

Copyright © 2016 Packt Publishing

All rights reserved. No part of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, without the prior written permission of the publisher, except in the case of brief quotations embedded in critical articles or reviews.

Every effort has been made in the preparation of this book to ensure the accuracy of the information presented. However, the information contained in this book is sold without warranty, either express or implied. Neither the authors, nor Packt Publishing, and its dealers and distributors will be held liable for any damages caused or alleged to be caused directly or indirectly by this book.

Packt Publishing has endeavored to provide trademark information about all of the companies and products mentioned in this book by the appropriate use of capitals. However, Packt Publishing cannot guarantee the accuracy of this information.

First published: March 2016

Production reference: 1110316

Published by Packt Publishing Ltd.

Livery Place

35 Livery Street

Birmingham B3 2PB, UK.

ISBN 978-1-78439-312-0

www.packtpub.com

Credits

Authors

Peter L. Newton

Jie Feng

Reviewer

Hamad A. Al-Hasan

Commissioning Editor

Edward Bowkett

Acquisition Editor

Larissa Pinto

Content Development Editor

Merint Thomas Mathew

Technical Editor

Dhiraj Chandanshive

Copy Editor

Shruti Iyer

Project Coordinator

Judie Jose

Proofreader

Safis Editing

Indexer

Tejal Daruwale Soni

Production Coordinator

Aparna Bhagat

Cover Work

Apar...

Table of contents

• Unreal Engine 4 AI Programming Essentials