Transcript lecture slides.

Object
Oriented
Design
Goals
 Discussion
Pacman Project
 Project X: OOA & D meets AI
 Collaborating
objects
 Objects approaching / or pretending to have
complexity of human beings
Pacman reflections
 Specification
 How
in UML
hard was it?
 How complete was the specification? Could
somebody else implement it?
How to
implement
Ghost.move
?
the big question
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
Homework 6
 Design
and
implement in
AgentSheets
 Individual
projects
 Due: Oct. 22
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
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 => Distributed Artificial Intelligence
How to spread
continuous values:
Diffusion
 Value
:= (value[left] + value[right] +
value[up] + value[down]) / 4
 Examples
 Temperature
 voltage
 Presence
Examples of Diffusion
 Bridge
Builder
 Avalanche / mudslide
 Electric Diffusion
 Electric Ink
 Heat Diffusion
Example
Asymmetric Diffusion
 Diffusion
coefficients representing
asymmetric diffusion can be introduced to
model...
 Water
flow (El Nîno)
 Wind (Sustainopolis)
 Value
:= 1/n ∑ui * valuei
Example 1: fire sim
Homework 6
 Design
and
implement in
AgentSheets
 Individual
projects
 Due: Oct. 22
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/
Description
Turn in

Project

Sims living in house or outside


Objects to satisfy basic needs






Hunger
Thirst
Sleep
Objects / people to satisfy secondary needs


At least 2 kinds of diffusions
Entertainment
Comfort
Documentation
Same naming conventions and guidelines as usual
… and use
“4448” as part of
your email
subject line!!