Chapter 2.2
Game Design
Overview

Game design as…


full-time occupation is historically new
field of practical study – even newer
2
Overview

Folk games [Costikyan]


“Traditional” games with cultural origins
Examples:





Tic-Tac-Toe (Naughts and Crosses)
Chess
Go
Backgammon
Poker
3
Overview

This introduction covers:




Terms
Concepts
Approach
All from a workaday viewpoint
4
Overview


There is no one “right” way to design
There are many successful approaches


Specific requirements and constraints of
each project and team determine what
works and what does not.
This introduction is but a scratch
5
The Language of Games

Game development – a young industry

Standards are still being formulated



Theory
Practice
Terminology
6
The Language of Games

Debate continues over high-level views

Lack of standard (concrete) definitions



Game
Play
High-level concepts tricky to articulate
7
The Language of Games

Workplace differences usually low-level

Working terminology

Example



“actors” instead of “agents”
“geo” instead of “model”
Workflow – how things get done


Individual responsibilities
Processes under which work is performed
8
The Language of Games

Why do we play?


What is the nature of games?


Not a designer’s problem
Not a designer’s problem
How is a game formed of parts?

A designer’s problem
9
The Language of Games

Our simplistic high-level definitions





Easy to modify to fit multiple cultures
Practical over metaphysically true
play
game
aesthetics
10
Play and Game

Play


Game


Interactions to elicit emotions
Object of rule-bound play
General enough to cover everything
11
Aesthetics and Frame

Aesthetics

Emotional responses during play


Naïve practical approach, not classical
Frame

The border of a game’s context


Inside the frame is in the game
Outside the frame is real life
12
Approaching Design

Computer games are an art form
Game design practices can be taught
Technical discipline like music, film, poetry

The art of making dynamic models


13
Approaching Design

A model represents something

Mental/Cognitive



Concepts
Beliefs
Maps


Mathematical



Equations
Formulas
Algorithms
Examples:


Locations
Relationships
14
Approaching Design

Abstract model

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
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
Conceptual and idealized
A tool for investigating specific questions
Simplifies thinking to help understand problems
May include assumptions thought to be false
Abstract game

One rule

The piece is moved to the open square
15
A Player-Game Model

A model of the player – game relationship
PLAYER
Mechanics
GAME
Interface
System
16
A Player-Game Model

Mechanics


Interface


Things the player does
Communication between player and game
System

Underlying structure and behavior
17
Control and State Variables

Defined by Isaacs in Differential Games

Control variables


Inputs from players
State variables

Quantities indicating game state
18
Play Mechanics

Gameplay



Feelings of playing a particular game
Activities engaged in a particular game
(Play/game) Mechanics


Specific to game activities
“What the player does”
19
Seven Stages of Action
Intention
to act
Sequence of
action
Execution of
action sequence
Evaluating
interpretations
Interpreting
perceptions
Perceiving
states
T HE GAME
Goals

Execution



Intention to act
Sequence of action
Execution of action
sequence

Evaluation



Evaluating interpretations
Interpreting perceptions
Perceiving states
20
Seven Stages of Action

A goal is formed



Models the desired state
The desired result of an action
Examples:



Have a glass of water in hand
Capture a queen
Taste ice cream
Intention
to act
Sequence of
action
Execution of
action sequence
Evaluating
interpretations
Interpreting
perceptions
Perceiving
states
T HE GAME
Goals
21
Seven Stages of Action

Goals turned into intentions to act

Specific statements of what is to be done
Intention
to act
Sequence of
action
Execution of
action sequence
Evaluating
interpretations
Interpreting
perceptions
Perceiving
states
T HE GAME
Goals
22
Seven Stages of Action

Intentions put into an action sequence

The order internal commands will be performed
Intention
to act
Sequence of
action
Execution of
action sequence
Evaluating
interpretations
Interpreting
perceptions
Perceiving
states
T HE GAME
Goals
23
Seven Stages of Action

The action sequence is executed

The player manipulates control variables
Intention
to act
Sequence of
action
Execution of
action sequence
Evaluating
interpretations
Interpreting
perceptions
Perceiving
states
T HE GAME
Goals
24
Seven Stages of Action

The state of the game is perceived

State variables are revealed via the interface
Intention
to act
Sequence of
action
Execution of
action sequence
Evaluating
interpretations
Interpreting
perceptions
Perceiving
states
T HE GAME
Goals
25
Seven Stages of Action

Player interprets their perceptions

Interpretations based upon a model of the system
Intention
to act
Sequence of
action
Execution of
action sequence
Evaluating
interpretations
Interpreting
perceptions
Perceiving
states
T HE GAME
Goals
26
Seven Stages of Action

Player evaluates the interpretations

Current states are compared with intentions and goals
Intention
to act
Sequence of
action
Execution of
action sequence
Evaluating
interpretations
Interpreting
perceptions
Perceiving
states
T HE GAME
Goals
27
Seven Stages of Action

Donald Norman’s approximate model


Actions not often in discrete stages
Not all actions progress through all stages
28
Seven Stages of Action

Scales to…

…an individual mechanic

A “primary element”


Examples:
 Move
 Shoot
 Talk
…an entire game

A generalized model of interaction
29
Designer and Player Models


Systems are built from designer mental models
Design models may only anticipate player goals
User's
Model
Design
Model
Designer
System
User
System Image
30
Designer and Player Models

Players build mental models from mechanics

Based upon interactions with the system image



The reality of the system in operation
Not from direct communication with designers
Player and designer models can differ significantly
User's
Model
Design
Model
Designer
System
User
System Image
31
Core Mechanics

Typical patterns of action

Fundamental mechanics cycled repeatedly

Examples:


Action shooters – run, shoot, and explore
Strategy game – explore, expand, exploit, exterminate

referred to as the “four X’s”
32
Premise


The metaphors of action and setting
Directs the player experience


Provides a context in which mechanics fit
Players map game states to the premise
33
Premise

Story is the typical example of premise


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Time
Place
Characters
Relationships
Motivations
Etc.
34
Premise

Premise may also be abstract

Tetris operates under a metaphor


The metaphor: arranging colored shapes
Encompasses all game elements

Player discussions use the language of the
premise
35
Premise


Games are models
Activities being modeled form premise


Actions may appear similar in model
Usually are fundamentally quite different

Sports games are good examples

Playing video games isn’t like playing the sport
36
Premise


Goes beyond setting and tone
Alters the players mental model

Basis of player understanding and strategy
37
Premise

Possible


Capable of happening in the real world
Plausible

Possible within the unique world of premise


“Makes sense” within the game’s premise
Consistent with the premise as understood
38
Choice and Outcome

Choice


Outcome


A question asked of the player
The end result of a given choice
Possibility space


Represents the set of possible events
A “landscape” of choice and outcome
39
Choice and Outcome

Consequence or Weight

The significance of an outcome


Greater consequences alter the course of the
game more significantly
Choices are balanced first by consequence
40
Choice and Outcome

Well-designed choice



Often desirable and undesirable effects
Should relate to player goals
Balanced against neighboring choices


Too much weight to every choice is melodrama
Orthogonal choices – distinct from others

Not just “shades of grey”
41
Qualities of Choice

Terms in which to discuss choices








Hollow – lacking consequence
Obvious – leaves no choice to be made
Uninformed – arbitrary decision
Dramatic – strongly connects to feelings
Weighted – good and bad in every choice
Immediate – effects are immediate
Long-term – effects over extended period
Orthogonal – choices distinct from each other
42
Goals and Objectives

Objectives

Designed tasks players must perform


Rigid requirements – formal
Goals

An intentional outcome


Notions that direct player action
Scales all levels of motivation


From selecting particular strategies…
…to basic motor actions (e.g. pressing a button)
43
Goals and Objectives
Find sword
Rescue dragon
Kill princess
Find sword
Kill dragon
Rescue princess
Designer

System
User
Objectives and goals can differ


Players goals reflect their understanding of the game
Designers must consider how the game communicates with players

Affordances – the apparent ways something can be used
44
Resources

Resources


Things used by agents to reach goals
To be meaningful, they must be…


Useful – provide some value
Limited – in total or rate of supply
45
Economies

Economies


Systems of supply, distribution, consumption
Questions regarding game economies:




What resources exist?
How and when will resources be used?
How and when will resources be supplied?
What are their limits?
46
Player Strategy
Situation

Result
People usually reason with commonsense


Action
A view of linear causation – cause and effect
Complex systems do not behave linearly

Players need information to support linear strategy
47
Game Theory

Game Theory



Utility


A measure of desire associated with an outcome
Payoffs


Branch of economics
Studies decision making
The utility value for a given outcome
Preference

The bias of players towards utility
48
Game Theory

Rational Players

Abstract model players – not real people



Always try to maximize their potential utility
Solve problems using pure logic
Always fully aware of the state of the game
49
Game Theory

Games of skill



Games of Chance



One-player games
Outcomes determined solely by choices
One-player games
Outcomes determined in whole or part by nature (chance)
Games of Strategy

Competitions between two or more players
50
Game Theory

Decision under certainty


Risky decisions


Players know the outcome of any decision
Probabilities of nature are known
Decision under uncertainty

Probabilities of nature are unknown
51
Interface

Interface


Input


Input, presentation, and feedback.
Player to game
Output

Game to player
52
Interface

Contains both hardware, software, and
performance elements.



Hardware such as game pads
Software such as engines
Performance such as pressing a button
53
Interface

Graphical user interface (GUI)

A visual paradigm of control
54
Interface

Typical perspectives:





First-person
Over-the-shoulder (OTS)
Overhead (top-down)
Side
Isometric
55
Interface

General categories of audio



Music
Sound effects
Dialog
56
Interface

Music

Powerful tool for establishing mood and theme
57
Interface

Controls


Physical input devices
Control inputs

User manipulations of the controls

They are not strategies


Example: a sequence of buttons to perform a combo
Strategies involve deciding when to perform
58
Interface

Key map or control table

A diagram showing control input, action,
and context
59
Interface

Control diagrams

Show input, action, and context
Action
Control
Context
Left
all
Right
all
Forward
all
Backward
all
Sprint
all
Pass
Offense
Lob
Offense
Shoot
Offense
Steal
Defense
Block
Defense
Hit
Defense
60
Interface

Front-end

In application software


The visible portion of the application
In games

GUI elements not displayed during play
61
Interface

HUD (Head-Up Display)



Displays during play
Shows and other information difficult to present
directly in the game environment
Examples






Scores
Resource levels
Mini Map
Chat
Alerts
Level
>need backup!!!
>No
>...
2
62
Interface

Mapping

An understood relationship between two things


Especially the relationship of a model to its subject
Examples
63
HCI and Cognitive Ergonomics

HCI – Human-Computer Interaction

Study of…




Communication between users and computers
How people design, build, and use interfaces
Better support for cooperative work
Cognitive Ergonomics

Analyzes the cognitive representations and
processes involved with performing tasks
64
Design of Everyday Things

Norman’s five principles of design

Visibility


Mappings


The perceived uses of an object
Constraints


Understandable relationships between controls and
actions
Affordances


Making the parts visible
Prevent the user from doing things they shouldn’t
Feedback

Reporting what has been done and accomplished
65
Systems

System

A set of interrelated components


Architecture



Their function and relationships form a whole
The particular arrangement of system elements
Game systems exist to enable play mechanics
Relationships between components determine
how the system works to produce results
66
Systems

Objects


Attributes


Properties determining what objects are
Behaviors


Pieces of a system
Actions the objects can perform
Relationships

How the behavior and attributes of objects affect
each other while the system operates
67
Systems

Two general approaches to design

Special case




Experiences built one scene/level at a time
Anticipate states while pre-scripting events
Solved by discovering the intentions of the designer
Systemic




General behaviors are designed
Scenes/Levels are specific configuations
Some events may still be pre-scripted
Solved by understanding the system
68
Systems

Emergent complexity


Emergence


Behaviors that cannot be predicted simply
from the rules of a system
Coined by George Henry Lewes in 1873
See: John Conway’s Game of Life
69
Systems

Dynamics


The behavior of systems over time
Generalizing dynamic behavior is hard

Dynamics determined by a given
architecture
70
Systems

Cybernetics

Study of communication, control, and regulation
71
Systems

A basic cybernetic system has:

Sensor – detects a condition


Comparator – evaluates the information


Thermometer
Switch
Activator – alters the environment when triggered by the
comparator
Activator
Comparator
Sensor
72
Systems

Feedback


The portion of a system’s output that is returned into the
system
Feedback Loop

The path taken by the feedback
Goal
Rate
Action
Information
Level
73
Systems

Positive feedback



Leads to runaway behavior
Difficult to make use of
Negative feedback


Leads to goal seeking behaviors
Most common form in systems
goal
Positive Feedback
Negative Feedback
74
Systems

Negative feedback





Stabilizes the game
Forgives the loser
Prolongs the game
Magnifies late successes

Positive feedback




Destabilizes the game
Rewards the winner
Can end the game
Magnifies early successes
Marc Leblanc
75
Systems

System Dynamics


Created by Jay Forrester 1956, MIT
A discipline for modeling and simulation


Originally a tool for policy analysis
Applicable to any system
76
Constraints

Platform

General description of hardware and software





Personal computer – PC, Mac, etc.
Console – Game Cube, PlayStation, Xbox, etc.
Handheld – DS, Game Boy Advance, PSP, etc.
Mobile device – Cel Phones, NGage, PDA, etc.
Arcade – custom vending games (e.g. Time Crisis)
77
Constraints

Game Saves




Save triggers
Save-anywhere
Save points
Coded text saves
78
Genres

Genre – a category describing
generalities of conventions, style, and
content
79
Genres








Action
Adventure
Arcade
Casual
Education
Fighting
First-person shooter
Platform








Racing
Rhythm
Role-Playing (RPG)
Simulation
Sports
Strategy
Puzzle
Traditional
80
Audiences

Target audience


Demographics


Group of expected consumers
Study of relevant economic and social
statistics about a given population
Demographic variables

The relevant factors
81
Audiences

Market

Demographic segmentation of consumers

Market segments


Smaller sub-segment of the market; more tightly defined
Demographic profile
 Typical consumer attributes in a market
82
Audiences

Heavy Users



Hardcore gamer


Those of the numeric minority of potential users responsible
for majority of sales of any product
“80/20 rule”
Game industry term for heavy video game users
Casual gamer

Game industry term for all other gamers
83
Audiences

Typically assumptions of the hardcore:







Play games over long sessions
Discuss games frequently and at length
Knowledgeable about the industry
Higher threshold for frustration
Desire to modify or extend games creatively
Have the latest game systems
Engage in competition with themselves, the game, and
others
84
Audiences

Why We Play Games – Nicole Lazzaro

Internal experience


Hard fun


Challenge of strategy and problem solving
Easy fun


Enjoyment from visceral activities
Intrigue and curiosity – exploration and adventure
Social experience

Stimulating social faculties – competition, teamwork,
bonding, and recognition
85
Iterating

Waterfall method



Development methodology
Design and production are broken into phases
Iterative development

Practice of producing things incrementally

Refining and re-refining the product
86
Iterating

Prototypes



Physical prototypes


Early working models of the product
Used to test ideas and techniques
Non-electronic models; physical materials
Software prototypes

Used regularly during iterative development
87
Iterating

Software testing


Tester


Person trained in methods of evaluation
Bug


Process of verifying performance and reliability of a software
product
Discrepancy between expected and actual behavior
Problem/Bug report

Description of the behavior of the discrepancy
88
Iterating

Focus test




Testing session using play-testers
Testers represent the target audience
Lots of feedback at one time
Data can be compromised by group think
89
Iterating

Tuning




Developing solutions by adjusting systems
Iterations are faster
Changes are less dramatic
Balance

Equilibrium in a relationship

Player relationships, mechanics, systems, etc.
90
Iterating

Intransitive relationships



Multiple elements offer weaknesses and strengths relative to
each other as a whole
Balanced as a group
Example: Rock-Paper-Scissors (RPS)
Heavy
Infantry
Archers
Cavalry
91
Creativity


Ability to create
Ability to produce an idea, action, or
object considered new and valuable
92
Creativity

Classic approach - Graham Wallace

Preparation


Incubation


Sudden illumination – Eureka!
Evaluation


Mulling things over
Insight


Background research and comprehension
Validating revealed insights
Elaboration

Transforming the idea into substance
93
Creativity

Brainstorming



Generating ideas without discrimination
Evaluation after elaboration
Can be unfocused
94
Creativity

Six Thinking Hats








White Hat – neutral and objective
Red Hat – intuition, gut reaction
Black Hat – gloomy, naysayer
Yellow Hat – Pollyannaish, optimistic
Green Hat – growth and creativity
Blue Hat – process and control
Symbolize perspective worn by people involved in the
creative endeavor
Edward de Bono
95
Inspiration

Board games





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Team competition
Temporal systems
Martial arts
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Serialized stories
Music


Continuity techniques
Television

Fantasy and agency
Sports


Dynamic narratives
Books
Film

Resource management
Paper RPGs

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Spatial relationships
Card games


Discipline in action
Children

Invention
96
Communication

Documentation


Methods vary widely
Written, descriptive model of the game

Depth varies according to the needs of the game
97
Communication

Treatment


A brief, general description of the game and the
fundamental concepts
May include:








Concept statement
Goals and objectives
Core mechanics and systems
Competitive analysis
Licensing and IP information
Target platform and audience
Scope
Key features
98
Communication

Other document types may include:







Preliminary design document
Initial Design Document
Revised Design Document
General Design Document
Expanded Design Document
Technical Design Document
Final Design Document
99
Communication

Flowcharts


A typical technique for diagramming steps in a
process
Most developers are familiar
Start/End
Process/
Action
Decision
Y/N
Delay
100
Communication
W andering
City
Start
Quest
No
Search for
Quest
No
Ye s
City
Quest Details
Ac cept
Recruit
Yes
Gather PC Allie s
Em bark/Split
Gather
Wilderness
Go to
Equip
Recruits
Seek Aid
Gear
Regroup
Artifacts
Assistance
Encounter
101
Communication

Associative diagram


Drawing that helps manage and organize information visually
Mind Map


A style of associative diagram
Key words and figures are placed on branches
weapon
fighting
range
102
Psychology

Working Memory

Holds roughly 7 ± 2 items at one time
while other cognitive operations on them
103
Psychology

Attention



Method of enhancing perceptions relative
to other stimuli in the same environment
How we focus on important things
Limited capacity
104
Psychology

Classical conditioning

Reaction to stimulus is conditioned by pairing with another
stimulus that elicits the desired response naturally
Before conditioning
Conditioning
After conditioning
105
Psychology




Unconditioned stimulus – Meat
Unconditioned response – Salivation over meat
Conditioned stimulus – Tone
Conditioned response – Salivation over tone
Before conditioning
Conditioning
After conditioning
106
Psychology

Operant conditioning


Learning by encouraging or discouraging
Operant

A response; the action in question


Example: pressing a button
Reinforcement contingency

Consistent relationship between the
operant and a result in the environment
107
Psychology

Reinforcers


Increase the probability an action will be repeated
Positive reinforcement

Positive stimulus that reinforces the behavior


Negative reinforcement

The removal or prevention of a negative stimulus


Ex. Use umbrella and be dry
Ex. Use umbrella and keep from getting wet
Punishment

Reduces the likelihood of a behavior with a stimulus

Ex. Being burned by a hot stove
108