I'm Morgan McGuire (@CasualEffects). I've been working on computer graphics and games for 20 years at great places including NVIDIA, Williams College, Brown University, and Activision.

See my home page for a full index of my blog posts, books, research, and projects.

Friday, July 8, 2016

PAC-MAN DX (Understanding Games #1)

This is the first in a series of articles describing my 2016 "Game Camp for Grownups" for introducing the medium of video games to colleagues in the humanities at Williams College.



“PAC-MAN Championship Edition DX+” (2010)
Directed by T. Iguchi, T. Iura, and R. Yabuchi
Developed by Mine Loader Software
Published by Namco Bandai for Xbox, Playstation, Windows, iOS, and Android

Widely considered a perfectly-designed game, “PAC-MAN DX” reinvents the maze-traversal legacy of PAC-MAN titles with modern advances for a gentle learning curve that still rewards hardcore play. The occasional tedium and frustration of the original are gone, and the graphics and audio have been updated to modern standards while retaining the cheer and minimalism that defined classic arcade style.

Play one of the versions of the game that uses a controller, not the iOS version with the touch screen controls. I presented the game on Windows using Xbox 360 controllers. (iOS with an external controller is fine if it supports one, but iOS controllers are rare.)


PAC-MAN Championship Edition DX+ Gameplay

Advances since PAC-MAN

The original PAC-MAN could be played at two levels of sophistication. Casual players enjoyed just moving around the maze eating dots, and rarely progressed beyond the opening stage. They were playing a “twitch” game. Hardcore players understood that it was fundamentally a strategy game about choosing paths and exploiting the ghost movement algorithms. That is, PAC-MAN is a traversal game at heart.

The original game lacked a bridge between the casual and hardcore styles of play. Thus, the really interesting part of the game was inaccessible to most players. “PAC-MAN DX” uses a series of mechanics to correct this. After the first few runs, you’ll find yourself operating primarily on a strategic basis. There is still a long path of building expertise to enjoy, with the top players able to score about 2000x as high as an average experienced player. Consider which mechanics deemphasize twitch and make strategy accessible, even while preserving the sensation of speed and reaction.

The original PAC-MAN

Gaming Literacy

PAC-MAN and the other games early in our series stand alone as great titles. However, we’re also using them to build literacy with gaming interfaces and terms. For example, “PAC-MAN DX” will teach you how to operate menus, steer a character using a controller, track your character on screen, and react quickly with these new controls. Those are essential skills before we before tackle the multiplayer game Monaco. In our other first few games, you'll learn or conventions including:
  • Floating colored letters = button or key to press
  • RT = right trigger
  • The B button is almost always "cancel or go back" and the A button means "accept"
  • The play area is fenced with invisible walls
  • Right stick = turn, left stick = walk
  • Many games have multiple features that must be unlocked by completing challenges
  • The player is intended to pillage crates and vases, even in friendly character’s houses
  • The triggers for game events are often misrepresented by prompts. E.g., if prompted, "escape before the house burns down", the house's collapse will probably be triggered by running out the door, not by a timer. In many games, you can't actually hold of the attacking mob--they will be replenished infinitely and you are intended to run from them.

Post-Game Exercises

We played the game on a large TV by taking turns and I loosely guided discussion among the resting players to hit the following points. Were I teaching a regular course, I would run that discussion in class and assign some parts as homework.

Mechanics

Games are composed of state, rules, and choices embedded in the rules. These are more obvious in board games. State is everything you’d have to write down if you had to stop in the middle of play, put the game away, and then resume the following day. Note that not every part of what is on the table is actually relevant game state. For example, the facing direction of a chess knight is irrelevant.

Rules are the instructions for what choices players can make, and how the state is affected by those choices. In a board game, these are printed out. For a video game, these are embedded in the program's source code, and are extremely complex compared to board games.

Strategy is a player's long-term plan for most or all choices in a game. Tactics are short sequences of choices, often in response to specific patterns of state. These are not an explicit part of the game. They emerge when players engage the game with goals in mind.

Respond to the following questions and challenges.  It may help to think of “PAC-MAN DX” as a board game with turns that are only 1/30-second long and run on a timer.
  1. Enumerate the game state in “PAC-MAN DX.” For example, the horizontal and vertical positions of PAC-MAN in pixels, the score, the position of each pellet...
  2. What are the choices in “PAC-MAN DX”? “Do nothing” is certainly one choice.
  3. Describe the rules for:
    1. Moving PAC-MAN. Tip: the player does not have direct control of the character!
    2. Eating ghosts
    3. Making dots appear
    4. Making fruit appear
    5. Ghost movement
    6. Points and game speed

Critique

One of many alternative graphics themes
An academic critique is not a review. The reader wants to understand the work and its relation to culture largely objectively, not primarily know your personal opinion or know if they should buy the game.

A critique always begins by concretely and quantitatively describing the work, then moving towards interpretation, and finally and closing with supported arguments around qualitative elements. For example, a film critique focused on cinematography might include statements such as:
Quantitative: the closing shot is a 16:9 shot of a sunset, with the red sun at the center framed by palm tree silhouettes on the outer thirds
Interpretation: the camera is fixed while the sun falls straight down, creating a vertical movement that contrasts the horizontal waves and leaves
Qualitative argument: this echoes the opening shot of a sunrise and tells us that the story is ending...it also indicates the off-screen death of the protagonist, whereas a sunrise might indicate a rescue
Each medium/genre/form (which I’ll collectively call “medium” for short) provides a set of conventions and techniques for communicating to the audience. Media are just that--sets of techniques, not rigid categories. I think of them as marks on a spectrum instead of boxes.

Any given work might leverage elements of multiple media. For example, Firefly was an episodic science fiction TV show. But it also leveraged the narrative structures of classic Western films, season-long arcs in the style of a miniseries, pop-culture characters and dialogue, and conventions of role playing games. It was Stagecoach meets Star Trek: The Next Generation meets Buffy the Vampire Slayer meets Dungeons and Dragons. Based on interviews with the director and writers, this was an intentional construction.

PAC-MAN using Dig-Dug graphics
When evaluating a work, it is important to choose the appropriate tools for the medium in critique. You’d evaluate a novel based partly on plot and characters, but a painting based on composition and line.  One advantage of starting with “PAC-MAN DX” is that it has essentially no characters or story. It thus foregrounds mechanics and helps us avoid the temptation to over-apply tools from film analysis to game critique. 

Many elements are shared across multiple media, but they cary different weight in each case. A critique should correspondingly emphasize the most structurally-important elements for a medium. For example, one could broadly rank the significance of elements of video games vs. (live action feature-) film media as:
Games: Mechanics > Set > Visuals > Characters > Music + SFX > Plot > Dialogue
Films:  Visuals > Music + SFX > Dialogue > Plot > Characters > Set
Respond to the following:
  1. Present and support your own ranking for the significance of film elements. I think visuals are objectively the most important, but there are many arguments for what should appear after that.
  2. Enumerate and rank the elements of critique for these media: 
    • Novels
    • Poetry
    • Feature film animation
    • Documentary
    • Classic broadcast episodic television
    • Streaming “television” (e.g., Netflix and Amazon shows)
    • Architecture
    • Dance
    • Plays
    • Musicals
    • Opera
  3. Make some one-sentence moderately interesting observations about the game without further discussion. For example,
    1. the ghosts holding the power-pellets carry the only weapon that can defeat them  
    2. slowing the game speed when PAC-MAN is about to be eaten removes much of the twitch and stress while emphasizing player heroism 
    3. since the music and visuals can be switched to those of other games such as Dig-Dug, obviously it is the mechanics that fundamentally define PAC-MAN vs. another game
    4. PAC-MAN DX borrows many mechanics from its predecessors and other series, but the original was one of the few truly original games, along with Pong, Tetris, and Space War [see the family tree in Koster]
  4. You’ve already begun a critique by objectively describing many of the mechanics of “PAC-MAN DX.” In about five minutes of oral presentation or two pages of writing, interpret the effect of some of those and then build a more subjective conclusion. For example:
    1. the sparks make the control scheme of moving the joystick before a turn clear, thus making fast play more accessible because the large time window for input is evident
    2. the PAC-MAN series enjoys pop-culture standing as the icon of video games [Newswire 2011] and a mythological position as a game independent of a target-market, despite the narrow demographic of top players. PAC-MAN DX exploits this reputation to engage players and then actually delivers the promise for the first time in the history of the series through accessible play and player-selected graphics and audio.

Recommended Reading

Koster, A Theory of Fun for Game Design, O'Reilly, 2013
See also the short presentation version PDF, and Koster's reflections PDF

You can read this book in about 90 minutes---it is more a set of comics and zen koans than a traditional text. Koster is a well-respected game writer who designed many large industry games.

As he notes in his reflections talk, he wrote this highly-acclaimed book in part because his game designs were not highly acclaimed. He wanted to get at what was going wrong with the large-scale titles and articulate the conventional wisdom of good designers which has largely been undocumented outside of the field.


Next in this series: Understanding Games #2: Monaco


Morgan McGuire (@morgan3d) is a professor at Williams College, a researcher at NVIDIA, and a professional game developer. His most recent games are Project Rocket Golfing for iOS and the Skylanders series for consoles. He is the author of the Graphics Codex, an essential reference for computer graphics now available in iOS and Web Editions.