This is the presentation of the article "Complexity at the cost of control in game design", presented at the CGAT 2012 conference Bali, Indonesia

1. Complexity at the cost of control in
game design?
Magnus Johansson
Department of
Computer and Systems
Sciences Stockholm
University, Sweden
magnus@dsv.su.se
Mirjam P. Eladhari
Department of Game
Design, Technology and
Learning Gotland
University
GOTLAND, SWEDEN
mirjam.eladhari@hgo.se
Harko Verhagen
Department of
Computer and Systems
Sciences Stockholm
University, Sweden
verhagen@dsv.su.se

2. Outline
• Introduction
• Background (the Model Social Game Agent)
• Surveys
• Interviews
• Discussion/ Conclusion
6/27/13 Magnus Johansson, Department of Computer and
Systems Sciences, Stockholm University, Sweden

3. Introduction

4. ”Most current video games do not, in fact contain
much real AI. The point of video games is to
entertain, not to simulate intelligence in depth, so
they usually contain just enough AI to make the
player feel as if the software is reasonably smart”
[Adams, p. 18, 2010]
6/27/13 Complexity at the cost of control in game design?

5. “Simulating human beings is the most difficult and
also the most important problem in game design”
[Adams, p. 18, 2010]
6/27/13 Magnus Johansson, Department of Computer and
Systems Sciences, Stockholm University, Sweden

6. Background

7. Preliminary definitions
“Systemic Artificial Intelligence” = A system that
dynamically adjusts the actions of the agent.
“Black Hole of AI”: “is always a black hole of AI,
where you are programming an incredibly
thoughtful, clever, brilliant AI behind the scenes.
And the player still reads it as a scripted
interaction” [Respondent 5]
6/27/13 Complexity at the cost of control in game design?

8. The Model Social Game Agent

9. Carley and Newell

10. Focus for interviews and surveys
• Navigation/pathfinding
• Strategy/Tactical choices
• Behavior adapted to context
• Decision making
• Memory of previous interactions
• Cooperation among NPCs
• Emotions
6/27/13 Magnus Johansson, Department of Computer and
Systems Sciences, Stockholm University, Sweden

11. Surveys

12. Current NPC Intelligence
• 9 respondents stated both decision-making and
cooperation between NPCs to be existing in
current games, while 5 claimed decision-making
missing.
• 5 respondents found memory existing in current
games.
• 4 respondents found emotions to exist in current
games.
• 10 respondents had implemented behavior
adapted to context and 2 of them reported the
implementation to be successful.
6/27/13 Complexity at the cost of control in game design?

13. What do you think these aspects could
add?
• Immersion, believability, realism and a more
emergent game experience.
• “Richer realizations” of characters, due to less
static authoring associated with NPCs.
• Memory a focus for many respondents, based on
the assumption that memory could add much
realism to interactions with NPCs.
• More context aware NPC behavior.
6/27/13 Magnus Johansson, Department of Computer and
Systems Sciences, Stockholm University, Sweden

14. How could the MSGA affect the play-
experience?
• Some respondents repeated their answers from
the previous question.
• Concerns raised about the “black hole of AI”,
that players simply do not recognize added
complexity.
• The behavior of dynamic NPCs not easily
understood by players.
• Increased interest through more complex
experiences.
• Added re-playability.
• Cohesion between events in games.
6/27/13 Magnus Johansson, Department of Computer and
Systems Sciences, Stockholm University, Sweden

15. How could the MSGA affect game
design?
• The Msga could open up new unexplored design
spaces.
• Alleviate some of the workload of game
designers.
• Potentially make game design much more
difficult.
• Would affect quest flow and story arch in ways
that need to be considered.
6/27/13 Complexity at the cost of control in game design?

16. Interviews

17. Relations between AI and game
design
• Game design and AI programming are both
highly specialized areas of expertise and game
designers rarely have the ambition to also
become skilled programmers.
• Designers often have new ideas or invent new
concepts that are difficult or impossible to
implement.
• Communication and knowledge between AI
programmers and Designers are sometimes
problematic for development teams.
6/27/13 Magnus Johansson, Department of Computer and
Systems Sciences, Stockholm University, Sweden

18. Current NPC Intelligence
• Systemic modeling vs Scripting.
• Path-finding a problem that all current games
have solved in a satisfying way.
• Interaction with NPCs stated as one of the
problems.
• Scripting limits possible interaction with NPCs
but mostly not seen as a problem.
• Conversation/dialogue trees a main strategy for
interaction with NPCs, but limited since the same
NPC will say the same phrase without contextual
awareness.
6/27/13 Complexity at the cost of control in game design?

19. Existing strategies
• Emotional states (faceGen)
• Limited memory in terms of saved emotional
states.
• Scripted behavior.
• Behavior trees.
• Scripted dialogues/conversation.
• Cooperation through faction systems (Oblivion)
only modestly successful.
• Systemic modeling of memory, cooperation and
emotions in games rare.
6/27/13 Magnus Johansson, Department of Computer and
Systems Sciences, Stockholm University, Sweden

20. How could the MSGA contribute?
• Add cooperative aspects to NPCs.
• Add a more durable memory for NPCs.
• Add emotions.
• Emotions and memory central contributions that
would be most beneficial for the interaction with
NPCs.
6/27/13 Complexity at the cost of control in game design?

21. Drawbacks with the MSGA?
• Only add a small marketable value.
• The “black hole of AI”.
• Would need obtrusive feedback to the user.
– No difference to the player if the AI is scripted or
systemic.
• Loosing control over the interaction in games.
• Possible threats to story structure.
• Testing/debugging becomes even more complex.
6/27/13 Magnus Johansson, Department of Computer and
Systems Sciences, Stockholm University, Sweden

22. Discussion/Conclusions
• Emotions and memory the most important
aspects of the MSGA
• Systemic AI difficult to control
• Social behavior/ Learning
• Games are complex systems, they should not be
chaotic systems.
• Existing genres not dependent on “smart” AI
• Consistency
• Limited scope of earlier attempts
6/27/13 Complexity at the cost of control in game design?

23. Discussion/Conclusions
• The MSGA not a solution to all situations
• The combination of traits of the MSGA not
implemented
• New game genres probably needed
6/27/13 Magnus Johansson, Department of Computer and
Systems Sciences, Stockholm University, Sweden

24. Future work
• Finish implementation of the MSGA.
• Evaluate players response of the MSGA.
• Find suitable game genres for the MSGA or even
create new ones.
• Identify what types of NPCs that would benefit
from being implemented as a MSGAs.
6/27/13 Complexity at the cost of control in game design?

25. Questions?

26. References
[1] Adams, E. Fundamentals of Game Design. Second Edition. New Riders. 2010
[2] Bartle, R. Designing virtual worlds. New Riders, 2003.
[3] Carley, K. M. and Newell, A. The nature of the social agent. Journal of
Mathematical Sociology, 19 (4): 221—262, 1994.
[4] Eladhari, M. P. (2010, September). Characterising Action Potential in Virtual Game
Worlds applied with the Mind Module. Retrieved from http://urn.kb.se/resolve?
urn=urn:nbn:se:hgo:diva-368.
[5] Janssen, M.A. and Jager, W. An integrated approach to simulating behavioural
processes: A case study of the lock-in of consumption patterns, Journal of Artificial
Societies and Social Simulation, 2 (2). 2000
[6] Johansson, M. Verhagen, H. Modelling the social fabric for normative NPCs in
MMOGs. The Society for the Study of Artificial Intelligence and the Simulation of
Behaviour (p. 79-84). 2010.

27. [7] Johansson, M. Verhagen, H. Eladhari, P, M. Model of social believable NPCs for
teacher training.CGames USA, Kentucky. 2011
[8] Johansson, M. Verhagen, H.“WHERE IS MY MIND”- THE EVOLUTION OF NPCS IN
ONLINE WORLDS. International Conference on Agents and Artificial Intelligence.
Rome. 2011
[9] Pinchbeck, D. An analysis of Persistent Non-Player Characters in the First-Person
Gaming genre 1998-2007: a case for the fusion of mechanics and diegetics.
Eludamos. Journal for Game Culture. 2009; 3 (2), p. 261-279
[10] Rabin, S. AI Game Programming Wisdom. Charles River Media. 2002.
[11] Salen, K. Zimmerman, E. Rules of Play ‐ Game Design Fundamentals. MIT Press,
2004.
[12] Tupes, E. C. and Christal, R. E. (1992). Recurrent personality factors based on
trait ratings. Journal of Personality, 60(2):225-251.

28. Games
Ubisoft Montreal. Assassins Creed (PC). Ubisoft. Eu-release date March 18th 2011.
Ion Storm Inc. Deus Ex (PC). Eidos Interactive, Eu-release date June 26th 2000.
3D Realms. Duke Nuke’em 3D (PC). GT Interactive. Eu-release date January 1996.
Mateas, M. Stern, A. Façade (PC). Release date July 2005
Rockstar North. Grand Theft Auto 4 (PC). Rockstar games. Eu-release date 3rd
December 2008
Quantic Dream. Heavy rain (PS3). Sony Computer Entertainment. Eu-release date
24th February 2010.
Team Bondi Rockstar Leeds. L.A Noir (PC). Rockstar Games. Eu-release date 11th
November 2011
Riot Games. League of Legends (PC). Riot games. Release date October 27th 2009.
Illusion Softworks. Mafia: City of lost heaven (PC). Gathering of Developers. Eu-
release date August 28th 2002.

29. Maxis. The Sims (PC). Electronic Arts. Release date February 2000.
KCEJ. Metal gear Solid (PC). Microsoft game studios. Release date September 3rd
1998.
Bethesda Game Studios. Oblivion The elder scrolls (PC). 2K Games, Bethesda
Softworks. Eu-release date March 24th 2006.
Id Software. Quake (PC). Activision/ Valve Corporation (Steam). Release date June
22nd 1996.
Bethesda Game Studios. Skyrim (PC). Bethesda Softworks. Release date November
11th 2011
Ubisoft Montreal. Splinter cell (PC). Ubisoft. Release date Noveber 17th 2002.
Blizzard Entertainment. World of Warcraft (PC). Blizzard Entertainment. Eu-release
date February 11th 2005.
Blizzard Entertainment. World of Warcraft, Wraith of the Lich King (PC). Blizzard
Entertainment. Eu-release date November 13th 2008.

30. Thank you for
listening!
magnus@dsv.su.se