Hardware and Procedural Constraints

1
Hardware and Procedural Constraints

• LCC 2700 Intro to Computational Media
• Fall 2005
• Ian Bogost

2
Affordances and Constraints

• Don Norman
• Doors and stovetops
• Physical and psychological properties that
  suggest and limit interaction
• But computers go beyond this

3
Standards

• Rules of production that facilitate consistent
  production
• Facilitate simplified modes of designing
  artifacts
• Facilitate better use of artifacts
• ISO guidelines, code standards, design best
  practices, standardized components, etc.

4
But

• Standards are difficult to enforce
• Standards may obscure their own problems and
  shortcomings
• ISO certification
• OSHA law
• Code standards professional practice
• Manufacturing interoperability (game theory)

5
Platforms vs. Standards

• Standards use external means to enforce their
  rules and constrain the expression possible under
  their guidance
• Platforms use material constraints to enforce
  their rules and constrain the expression possible
  under their imposition
• Standards are top-down, enforcing systems
• Platforms are sometimes top-down affairs, where
  the material enforcement is known to the platform
  designers
• Platforms are more often bottom-up affairs, where
  the material enforcement comes from the
  unexpected arrangement of seemingly incidental
  features

6
Auto manufacturing

• The Dodge Neon and the PT Cruiser
• The Toyota Camry and the Lexus RX 330
• The VW Touareg and the Porsche Cayenne
• The Ford F-150 and the Ford Chassis Cab Towtruck

7
Coin-On Arcade Machines

• 2 - 3 minute play goals
• Pick-up controls
• Sinistar example

8
ENIAC , 1940s(Electrical Numerical Integrator
and Calcultaor)

• 18,000 vacuum tubes and 2,000 square feet of
  footprint
• Programmatic instructions in separate parts of
  the machine
• Segments needed to be plugged together for any
  particular computational task
• Programming required considerable physical effort
• John von Neumann and others realized this
  limitation
• The conditional control transfer or
  stored-program technique
• Execution based on programmatic need rather than
  physical arrangement

9
Pong and Tank

• Pong in 1972, a surprise arcade hit
• Distribution practices and Kee Games (Al Alcorn)
• Pong vs. Tank (1974)
• Steve Bristow
• The predecessor of Atari Combat

10
MS-DOS memory structure

• Conventional Memory
• Contiguous memory directly used by the 8086 in
  real mode
• 0 to 640kb
• Even though the chip could address 1MB, IBM
  reserved the upper memory for ROM c.
• Expanded Memory
• Up to 32MB expansion on any machine
• Apps must be written to use it
• Extended Memory
• Past the first 1MB of address space
• 286 and up supports it
• Addressable by applications in Real mode
• DOS programs use this memory for storage and
  swapping to Conventional

11
MS-DOS memory structure

• Issues
• Loading the app into 640kb or less RAM, then
  using Extended and Expanded memory to swap
• Lotus 1-2-3 could only store cell labels and not
  values in expanded memory
• Large programs (esp games) required a great deal
  of conventional memory, which was often a
  configuration problem
• Leading to
• Memory managers (e.g. LOADHIGH), config.sys woes,
  etc.
• In comparison, other OSs provide one contiguous
  physical space for memory, accessible to the
  programs at all times
• Windows (later versions 3.x ran atop DOS!)
• Unix
• OS/2

12
Game Engines

• The First Person Shooters affordances?
• Abstracted and encapsulated into Engines Quake
• Features
• 3D rendering
• Physics
• Sound management
• Artificial Intelligence
• Network Communication
• Scripting
• Tools

13
Ways to use Game Engines

• Doom, Quake, HeXen, etc.
• (Metal Gear), Deus Ex, Thief, Splinter Cell, etc.
  
• Future?
• Improved bump mapping, particle effects, fresnel
  effects, and volumetric effects (HL2)
• synchronized behaviors, preconditions, success
  tests, priority, atomic behaviors, goals, and
  subgoals (ABL)

14
Videogame First Party Licensing

• Nolan Bushnell sold Atari to Warner Communication
  in 1977
• A glut of titles flooded the market in the early
  1980s.
• Pac-Man (more carts than consoles)
• E.T. ( in the NM desert)
• I could put dogshit in a cartridge
• The videogame crash of 1983-1984
• Nintendo renews the market in 1986 with the NES,
  sold as a toy (not a videogame system)
• Tightly controlled first-party licensing is
  introduced

15
Next-Gen Videogame Consoles

• (from Chris Heckers GDC 2005 rant)
• Engine Code vs. Gameplay Code
• Engine Code
• Graphics, physics, etc.
• Huge homogenous data structures
• easy to write this code (even if it has a lot
  of math in it)
• Does something very predictable
• Gameplay (and AI) Code
• Branching, parameterizing, etc. mostly
  exceptions
• Does something unpredictable (this is what makes
  the game work, well.
• Modern CPUs (Pentium Pro and later) support OUT
  OF ORDER execution
• Vs. IN ORDER OOO rearranges the code to best
  take advantage of the processor
• But Xenon and Cell (Xbox 360 and PS3) are IN
  ORDER processors!
• Makes gameplay code hard to write, and hard to
  run efficiently
• Why? And why do we care?

16
Next-Gen Videogame Consoles

• Modern CPUs (Pentium Pro and later) support OUT
  OF ORDER execution
• Vs. IN ORDER OOO rearranges the code to best
  take advantage of the processor
• But Xenon and Cell (Xbox 360 and PS3) are IN
  ORDER processors!
• Makes gameplay code hard to write, and hard to
  run efficiently
• Why? And why do we care?

17
The Atari VCS (2600)

• Based on the success of Pong and the Pong home
  consoles
• A console for Pong-like games
• The board design and memory architecture is
  designed for Pong-like games
• A playfield backdrop
• Two player sprites
• Two missiles
• One ball
• Modified 6502 (Apple II) core with 13 of 16 bits
  available, called 6507
• The Television Interface Adapter (TIA) for
  graphics
• 3 registers
• 128 bytes RAM
• 2 kilobytes on ROM (increased to 4k and higher
  over time)

18
The Atari VCS (2600)

• Designed for games like Pong and Combat
• Examples
• 40 blocks of playfield, but 20 bits of playfield
  memory?
• Hardware wraparound
• Pitfall?
• Grand Prix?