Object Oriented Design

1
Object Oriented Design
2
Goals

• Discussion Pacman Project
• Project X OOA D meets AI
• Collaborating objects
• Objects approaching / or pretending to have
  complexity of human beings

3
Pacman reflections

• Specification in UML
• How hard was it?
• How complete was the specification? Could
  somebody else implement it?

4
How to implement Ghost.move?

• the big question

5
Object interaction complexity

• 1970s
• Frogger simple causality truck hits frog
• Space Invaders indirect causality Defender
  shoots laser, laser hits spaceship
• 1980s
• Pacman early AI tracking, avoiding, of objects.
  E.g., ghosts track the pacman
• 1990/2000s
• Simulation of human intentions, goals, emotions,
  communication, name that game

6
Homework 6

• Design and implement in AgentSheets
• Individual projects
• Due Oct. 22

7
Diffusion and Hill Climbing

• The presence of an agent can be diffused through
  space allowing other agents to track agent via
  hill climbing
• The landscape can be shaped to provide navigation
  clues

8
Solution combine hill climbing with diffusion

• Powerful idea
• applicable to a huge number of OO design problems
• A cognitive tool to think about complex problems
• Origins
• Hill climbing Artificial Intelligence
• Diffusion Physics
• Combination gt Distributed Artificial Intelligence

9
How to spread continuous values Diffusion

• Value (valueleft valueright valueup
  valuedown) / 4
• Examples
• Temperature
• voltage
• Presence

10
Examples of Diffusion

• Bridge Builder
• Avalanche / mudslide
• Electric Diffusion
• Electric Ink
• Heat Diffusion

11
Example
12
Asymmetric Diffusion

• Diffusion coefficients representing asymmetric
  diffusion can be introduced to model...
• Water flow (El Nîno)
• Wind (Sustainopolis)
• Value 1/n ?ui valuei

13
Example 1 fire sim
14
Homework 6

• Design and implement in AgentSheets
• Individual projects
• Due Oct. 22

15
Background

• Created in 2000 by Will Wright at Maxis, an
  Electronic Arts company
• Grew out of series of simulation games including
  SimCity (also created by Will in 1989), SimAnt,
  SimTower, SimEarth,
• Info http//www.thesims.com/

16
Description
17
Turn in

• Project
• Sims living in house or outside
• At least 2 kinds of diffusions
• Objects to satisfy basic needs
• Hunger
• Thirst
• Sleep
• Objects / people to satisfy secondary needs
• Entertainment
• Comfort
• Documentation
• Same naming conventions and guidelines as usual

18
and use 4448 as part of your email subject
line!!