J e f f    O r k i n MIT Media Lab | Cognitive Machines jorkin@alum.mit.edu http://www.jorkin.com
Goal-Oriented Action Planning (GOAP)
WHAT is GOAP? Goal-Oriented Action Planning (aka GOAP, rhymes with soap) refers to a simplfied STRIPS-like planning architecture specifically designed for real-time control of autonomous character behavior in games. I originally implemented GOAP for F.E.A.R. while working at Monolith Productions. This A.I. architecture simultaneously powered Monolith's Condemned: Criminal Origins. (Brian Legge was responsible for the A.I. in Condemned). My GOAP implementation was inspired by conversations within the A.I. Interface Standards Committee's (AIISC) GOAP Working Group, as well as ideas from the Synthetic Characters Group's C4 agent architecture at the MIT Media Lab, and Nils Nilsson's description of STRIPS planning in his AI book.    GOAP RESOURCES by JEFF ORKIN [paper] [slides] 3 States and a Plan: The AI of F.E.A.R. (GDC 2006) [paper] [slides] Agent Architecture Considerations for Real-Time Planning in Games (AIIDE 2005) [paper] [slides] Symbolic Representation of Game World State: Toward Real-Time Planning in Games (AAAI Challenges in Game AI Workshop 2004) Applying Goal-Oriented Planning for Games (draft for AI Game Programming Wisdom 2, 2003)    GOAP RESOURCES by OTHERS An Overview of the AI Architecture Inside the F.E.A.R. SDK - AIGameDev.com Assaulting F.E.A.R.'s AI: 29 Tricks to Arm Your Game - AIGameDev.com Special Report: Goal-Oriented Action Planning (membership required) - AIGameDev.com How AI in Games Works: The Planning System - bit-tech.net Practical Development of Goal-Oriented Action Planning AI - David Pittman's MS Thesis Enhanced NPC Behaviour using Goal Oriented Action Planning - Edmund Long's MS Thesis StarPlanner: Demonstrating the use of planning in a video game - Panagiotis Peikidis's B.Sc. Thesis Threat Analysis Using Goal-Oriented Action Planning - Philip Bjarnolf's B.Sc. Thesis Improved Missile Route Planning and Targeting using Game-Based Computational Intelligence - Ken Doris & David Silvia (CISDA 2007) *Email me to add a resource.    GOAP IMPLEMENTATIONS F.E.A.R. SDK v1.08 - includes complete A.I. source code GPGOAP: General Purpose Goal Oriented Action Planning - Bram Stolk's open source GOAP implementation ReGoap: Generic C# GOAP library with Unity3d examples - Luciano Ferraro's open source GOAP implementation *Email me to add an implementation.	GAMES USING GOAP ARCHITECTURES F.E.A.R. (X360/PS3/PC) - Monolith Productions/VU Games, 2005 Condemned: Criminal Origins (X360/PC) - Monolith Productions/Sega, 2005 S.T.A.L.K.E.R.: Shadow of Chernobyl (PC) - GSC Game World/THQ, 2007 Mushroom Men: The Spore Wars (Wii) - Red Fly Studio, 2008 Ghostbusters (Wii) - Red Fly Studio, 2008 Silent Hill: Homecoming (X360/PS3) - Double Helix Games/Konami, 2008 Fallout 3 (X360/PS3/PC) - Bethesda Softworks, 2008 Empire: Total War (PC) - Creative Assembly/SEGA, 2009 F.E.A.R. 2: Project Origin (X360/PS3/PC) - Monolith Productions/Warner Bros, 2009 Demigod (PC) - Gas Powered Games/Stardock, 2009 LMNO (working title) (X360/PS3) - Electronic Arts Just Cause 2 (PC/X360/PS3) - Avalanche Studios/Eidos Interactive, 2010 Transformers: War for Cybertron (PC/X360/PS3) - High Moon Studios/Activision, 2010 Trapped Dead (PC) - Headup Games, 2011 Deus Ex: Human Revolution (PC/X360/PS3) - Eidos Interactive, 2011 *Email me to add a game.    RELATED RESOURCES Creature Smarts: The Art and Architecture of a Virtual Brain - Synthetic Characters Group, MIT Media Lab (GDC 2001) GOAP Working Group Report - 2004 AIISC Report Planning Domain Definition Language (PDDL) - several versions linked from Drew McDermott's web page Simple Hierarchical Ordered Planner (SHOP) - University of Maryland Hierarchical Plan Representations for Encoding Strategic Game AI - Hai Hoang, Stephen Lee-Urban & Hector Munoz-Avila (AIIDE 2005) SquadSmart: Hierarchical Planning and Coordinated Plan Execution for Squads of Characters - Peter Gorniak & Ian Davis (AIIDE 2007) Connecting PDDL-based off-the-shelf planners to an arcade game - Olivier Bartheye & Eric Jacopin (ECAI AIG 2008) *Email me to add a resource.    RELATED BOOKS AI Game Programming Wisdom 2 - Edited by Steve Rabin AI Game Programming Wisdom 4 - Edited by Steve Rabin Automated Planning: Theory & Practice - Paolo Traverso, Malik Ghallab, and Dana Nau Artificial Intelligence: A New Synthesis - Nils J. Nilsson Artificial Intelligence: A Modern Approach - Stuart Russell and Peter Norvig