Collected Wisdom of Game AI Professionals

697 Pages·2017·10.32 MB·English

by  Steve Rabin

Game AI Pro 3
Game AI Pro 3
Collected Wisdom of Game AI Professionals
Edited by
Steve Rabin
CRC Press
Taylor & Francis Group
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Contents
Preface
Web Materials
Acknowledgments
About the Editors
Contributors
Section I General Wisdom
1 The Illusion of Intelligence
Steve Rabin
2 Creating the Past, Present, and Future with Random Walks
John Manslow
3 Logging Visualization in FINAL FANTASY XV
Matthew W. Johnson, Fabien Gravot, Shintaro Minamino, Ingimar Hόlm
Guðmundsson, Hendrik Skubch, and Youichiro Miyake
4 What You See Is Not What You Get: Player Perception of AI Opponents
Baylor Wetzel and Kyle Anderson
5 Six Factory System Tricks for Extensibility and Library Reuse
Kevin Dill
6 Debugging AI with Instant In-Game Scrubbing
David Young
7 But, It Worked on My Machine! How to Build Robust AI for Your Game
Sergio Ocio Barriales
Section II Architecture
8 Modular AI
Kevin Dill and Christopher Dragert
9 Overcoming Pitfalls in Behavior Tree Design
Anthony Francis
10 From Behavior to Animation: A Reactive AI Architecture for Networked
First-Person Shooter Games
Sumeet Jakatdar
11 A Character Decision-Making System for FINAL FANTASY XV by Combining
Behavior Trees and State Machines
Youichiro Miyake, Youji Shirakami, Kazuya Shimokawa, Kousuke Namiki,
Tomoki Komatsu, Joudan Tatsuhiro, Prasert Prasertvithyakarn, and
Takanori Yokoyama
12 A Reusable, Light-Weight Finite-State Machine
David “Rez” Graham
13 Choosing Effective Utility-Based Considerations
Mike Lewis
14 Combining Scripted Behavior with Game Tree Search for Stronger, More
Robust Game AI
Nicolas A. Barriga, Marius Stanescu, and Michael Buro
Section III Movement and Pathfinding
15 Steering against Complex Vehicles in Assassin’s Creed Syndicate
Eric Martel
16 Predictive Animation Control Using Simulations and Fitted Models
Ingimar Hόlm Guðmundsson, Hendrik Skubch, Fabien Gravot, and
Youichiro Miyake
17 Fast Cars, Big City: The AI of Driver San Francisco
Chris Jenner and Sergio Ocio Barriales
18 A Unified Theory of Locomotion
Graham Pentheny
19 RVO and ORCA: How They Really Work
Ben Sunshine-Hill
20 Optimization for Smooth Paths
Mark Langerak
21 3D Flight Navigation Using Sparse Voxel Octrees
Daniel Brewer
22 Faster A* with Goal Bounding
Steve Rabin and Nathan R. Sturtevant
23 Faster Dijkstra Search on Uniform Cost Grids
Nathan R. Sturtevant and Steve Rabin
Section IV Tactics and Strategy
24 Being Where It Counts: Telling Paragon Bots Where to Go
Mieszko Zieliński
25 Combat Outcome Prediction for Real-Time Strategy Games
Marius Stanescu, Nicolas A. Barriga, and Michael Buro
26 Guide to Effective Auto-Generated Spatial Queries
Eric Johnson
27 The Role of Time in Spatio-Temporal Reasoning: Three Examples from
Tower Defense
Baylor Wetzel and Kyle Anderson
28 Pitfalls and Solutions When Using Monte Carlo Tree Search for Strategy and
Tactical Games
Gijs-Jan Roelofs
29 Petri Nets and AI Arbitration
Sergio Ocio Barriales
30 Hierarchical Portfolio Search in Prismata
David Churchill and Michael Buro
Section V Character Behavior
31 Behavior Decision System: Dragon Age Inquisition’s Utility Scoring
Architecture
Sebastian Hanlon and Cody Watts
32 Paragon Bots: A Bag of Tricks
Mieszko Zieliński
33 Using Your Combat AI Accuracy to Balance Difficulty
Sergio Ocio Barriales
34 1000 NPCs at 60 FPS
Robert Zubek
35 Ambient Interactions: Improving Believability by Leveraging Rule-Based AI
Hendrik Skubch
36 Stochastic Grammars: Not Just for Words!
Mike Lewis
37 Simulating Character Knowledge Phenomena in Talk of the Town
James Ryan and Michael Mateas
Section VI Odds and Ends
38 Procedural Level and Story Generation Using Tag-Based Content Selection
Jurie Horneman
39 Recommendation Systems in Games
Ben G. Weber
40 Vintage Random Number Generators
Éric Jacopin
41 Leveraging Plausibility Orderings to Achieve Extremely Efficient Data
Compression
Jeff Rollason
42 Building Custom Static Checkers Using Declarative Programming
Ian Horswill, Robert Zubek, and Matthew Viglione
Index
Preface
Welcome to an all new volume of Game AI Pro! As with each book in this series,
I am proud to deliver brand new material from 50 of the top developers and
researchers in the field of game AI. With 42 chapters of innovative techniques and
algorithms, I am humbled at the goodwill and sharing of wisdom that this work
represents. This book is a testament to the generous community of game AI
developers as well as the larger game development community. Everyone
involved in this effort believes that sharing information is the single best way to
rapidly innovate, grow as developers, and continue to move the game industry
forward. We sincerely hope that you will benefit from the insights and wisdom
held within this book.
This book is divided into six primary sections. In the first section, “General
Wisdom,” we have a selection of techniques that generally apply to all games. In
the “Architecture” section, we further explore modern architectures such as
behavior trees and share architectures used in top games such as FINAL FANTASY
XV, the Call of Duty series, and the Guild Wars series. In the “Movement and
Pathfinding” section, we explore ways to better smooth paths, avoid obstacles,
and navigate 3D space, and present cutting-edge techniques to speed up A* and
Dijkstra. The “Tactics and Strategy” section focuses largely on combat decisions
made in a wide variety of genres such as RTS, RPG, MOBA, strategy, and tower
defense games. In the “Character Behavior” section, we look at individual AI
behavior such as character interactions, modeling knowledge, efficient simulation,
difficulty balancing, and making decisions with case studies from both
commercial games (Paragon, Dragon Age Inquisition, and FINAL FANTASY XV)
and indie games (Project Highrise and Talk of the Town). Finally, we end with
the “Odds and Ends” section that contains chapters on specialized AI topics
ranging from recommendation systems to random number generation and
procedural content generation.
Right now, the game AI community is larger than ever and I want to invite you
to discover all of the wonderful resources that are available. In addition to
reading about new game AI techniques in the “Game AI Pro” book series, there