Glossary

This section includes brief definitions of a number of the terms referred to in this book, and should be of particular use to readers less familiar with the jargon of the computer and video game industry. Some of the definitions veer close to talking about programming, and in these cases I provide only enough information to give the reader a general idea of what the termmeans. Those looking for more complete definitions are advised to pick up a book about computer game development from a programming standpoint, of which there are many.

A*:

The most popular pathfinding algorithm used by computer games, which finds short and effective paths consistently and quickly, though it is far from perfect. The basis of the A* algorithm is to search for a path by expanding valid nodes that are closest to the target location first in order to try to find the shortest path possible without searching too extensively. Of course, this can be found described in more detail in almost any book about programming games . See also Pathfinding .

Agent:

See AI Agent .

AI:

See Artificial Intelligence.

AI Agent:

The entity that the artificial intelligence controls in a game; the agent of its actions. In a computer game, the AI agents include the monsters the player fights and the NPCs to which he talks. Many people make the mistake of referring to those creatures themselves as AIs, but this has always bothered me. Just as you would not say that a person walking down the street is an intelligence, you should not refer to the agents in a game as the AIs. See Chapter 9, Artificial Intelligence.

Algorithm:

In the land of game development this refers to a usually short piece of code designed to solve a particular problem, typically mathematical in nature. For instance, you might have an algorithm that determines whether one character in a 3D environment can see another one or not. Or you could say that the code that finds a walkable path from the first character to the second one is an algorithm. Or, in a game like SimCity , algorithms are used to calculate the population density in a given location based on the choices the player has made in building the city.

A-Life:

See Artificial Life .

Alpha:

Customarily describes a game that is not yet close to being complete but is playable all the way through. At this point, the design and content is largely done, and bug-fixing, refining, and balancing are all that remain to be done on the title. This is often used by publishers to define the state of a project they have in development and is typically followed by the Beta state. Other developers may define Alpha differently, such as using it to mean any game that is in a playable state. See also Beta and Release Candidate .

Arcade Game:

Strictly speaking, a computer game that is found in an arcade environment. It may also refer to home conversions of the same games. More broadly, arcade game describes any game featuring the short and intense gameplay typical of these games. See Chapter 4, which contains an analysis of the arcade game Centipede and an exploration of the nature of the arcade game as a genre .

Art:

In the context of game development, this is most often used to describe the graphical content of a game. It can also mean what all game developers engage in, the creation of computer games themselves, which qualify as art. The author s favorite definition of art comes from Chapter 7 of Scott McCloud s excellent book Understanding Comics : Art, as I see it, is any human activity which doesn t grow out of either of our species two basic instincts : survival and reproduction. Some game developers spend endless time debating whether or not computer games qualify as art, but these arguments are seldom productive or useful.

Art Bible:

A document used in game development that includes concept sketches of game art assets and possibly some descriptive text. The art bible is used by a game s art team as a reference tool in the development of the game s graphical content, usually in order to maintain consistency.

Artificial Intelligence:

The artificial intelligence in a game controls all of the entities or agents in the game that have the ability to react to the player or otherwise provide an unpredictable challenge for the player. Artificial intelligence in a singleplayer game typically fulfills the role that human intelligence provides in a multi-player game. Thoroughly defined in Chapter 9, Artificial Intelligence.

Artificial Life:

A system for artificial intelligence that tries to imitate biological life by assigning AI agents base behaviors and desires, which cause them to perform specific actions by their nature. This is the opposite of the type of AI typically used in most games, though artificial life was famously used in the computer game Creatures .

Assets:

The content of a game; customarily used to refer to the art, sound effects, music, and possibly the levels. Code itself is seldom referred to as an asset.

Avatar:

The same as a game-world surrogate, the player s avatar is whatever character represents him in the game-world. It may also be an icon used in chat-room-like situations. The Avatar is also the name of the character the player controls in the Ultima series of games.

Beta:

The state games reach after passing through Alpha, and the last step before a game is published or otherwise released to the public. In Beta, changes made to a game are supposed to be strictly limited to bug fixes. Some developers define Beta to be when they first have what they consider to be a release candidate. See also Alpha and Release Candidate .

Bible:

Used in the gaming industry to refer to various reference materials used during a game s development. See Art Bible and Story Bible .

Blind-Play:

In multi-player gaming, this refers to each player being able to make his moves without the other players being able to see them; the other players are blind to their actions. In non-computer games, this is typically accomplished via a physical screen of some type that is placed between different players, or between a Game Master and his players. In computer gaming, blind-play is most common in online gaming, where each player has his own computer system and thereby cannot always see what the other players are doing.

Boss Monster:

An enemy in a game, though not necessarily a monster per se, that is much larger or simply more difficult to defeat than the other opponents in the game. Typically boss monsters are placed at the end of levels and provide a climax for that level s gameplay.

Bot:

Short for robot, this refers to artificial intelligence agents that are designed to appear to play similarly to humans , typically designed to work in first-person shooter death-match games. Quake III Arena and Unreal Tournament both feature bots as the player s only opposition in the single-player game.

BSP:

Short for Binary Space Partition. A method for storing and rendering 3D space that involves dividing the world into a tree of space partitions, most famously used in id Software s games Doom and Quake .

Builder Games:

One termused to describe games in which the player is responsible for building lasting structures in the game-world. In a sense, in builder games, the players are responsible for the level design. Examples of this type of game are SimCity , Civilization , RollerCoaster Tycoon , and The Sims .

Burn Rate:

The amount of money a company, typically a developer, spends in a month to keep itself in business. This typically includes all of the employees salaries, rent, utilities, and other persistent expenses. Sometimes publishers will try to fund a developer only to the extent of its burn rate, so that the developer does not have any spare cash and remains forever beholden to the publisher.

Candidate:

See Release Candidate .

Canned:

Another term for scripted, though canned is typically used more derisively. See Scripted .

Capture the Flag:

A game involving two teams , both of which have a flag. The flag is kept at a specific location and possibly guarded , while the players on both teams try to grab the other team s flag through stealth or brute force. In computer games, this is often a game variant offered in first-person shooter multi-player cooperative games, such as Quake or Unreal .

Choke -Point:

A point in a game past which a player can progress only by passing through a particular area, completing a particular puzzle, or defeating a particular monster. Often the areas preceding and following a choke-point allow the player more freedom of play, while the choke-point presents a task the player absolutely must accomplish before proceeding.

Classic Arcade Game:

This does not necessarily mean a game that is a classic, but any game that was released during the early period of arcade games or that exhibits the traits typical of those games. Classic arcade games include simple, singlescreenplayer games such as Space Invaders , Centipede , Robotron: 2084 , or Pac-Man. Classic arcade game is defined more fully in Chapter 4. See also Arcade Game .

Code:

When used in reference to games, code is the lines of text that programmers enter into the computer and which the computer then compiles into the functional game. A talented programmer is sometimes referred to as a code-jockey.

Color :

Beyond the obvious definition, in terms of game design this may also refer to the specific content and setting of a game. Monopoly , for instance, includes the street names of Atlantic City and a Depression era real-estate mogul theme as a means of providing color. Color is separate from the gameplay itself.

Concept Document:

Also known as a pitch document. This is a short document that includes text and concept sketches and that is used to initially sell the idea of a project to a publisher or other financier. A concept document gives the reader an idea of what the game will involve without including sufficient detail to actually develop the game. If accepted, the concept document is usually expanded into the design document.

Concept Sketch:

A sketch of a particular game art asset that is used to show someone what the art will look like, approximately, before that graphic or model is actually created. May also be a sketch of a scene from the game as it will appear once the game is functional.

Creative Services:

A deceptively titled wing of the publisher that is typically in charge of creating the box art and other advertisements and logos for a game.

Critical Path:

The path that the player is expected and encouraged to follow when moving through a game or a particular level. Somewhat reminiscent of the yellow brick road in The Wizard of Oz .

CRPG:

A computer version of a role-playing game. See also Role-Playing Game .

CTF:

Typically refers to capture the flag multi-player games, though it may also refer to Valve Software s Classic Team Fortress game. See Capture the Flag .

Cut-Scene:

A non-interactive portion of a game typically used to communicate to the player information about the game s story line, sometimes involving pre-rendered or live action full-motion video, other times using the game s real-time graphics engine. Cut-scenes often come between levels in a game, and are sometimes used as rewards for the player having finished a particularly challenging portion of the game.

Death March :

When a development team, particularly the programmers, works every waking moment on a project for a long period of time, typically trying to make an unachievable deadline of some sort . Often the death march is entered into thinking it will be over soon enough, but it then drags on long beyond what anyone thought possible.

Death-Match:

A multi-player game in which the players only goals are to kill each other. Usually refers to games of that sort in first-person shooters such as Half-Life, Unreal , or Halo .

Decision Tree:

A type of chart that shows how various player decisions will lead to different outcomes . Referred to as a tree, since each fork produces two branches that move away from the previous decision, making it look like a tree.

Design Document:

The textual reference used in developing a game that attempts to describe in detail every important aspect of the game s design. Sometimes referred to as the functional specification. Described more completely in Chapter 19, The Design Document.

Designer s Story:

This is the story written by the designer or someone on the development team that the game follows . This story is completely predetermined, even if it has a number of different paths for the player to explore.

DM:

Depending on the context, see Dungeon Master or Death-Match.

Dungeon Master:

The term for the Game Master used in conjunction with Dungeons & Dragons games. See Game Master.

Emergence:

In terms of a game, emergence is when unanticipated behaviors and results emerge out of the various game systems interacting with each other and with the player s input. In short, emergence is when the game experience takes a direction the designer never anticipated. Some emergent behaviors may turn into player exploits, which are generally viewed as a negative form of emergence, while other emergent behaviors just mean players are able to author their own experience without ruining it. Some designers view any amount of emergence as a negative, though most would agree emergence is one of the most exciting parts of game design.

Emoticons:

Somewhat odious slang expression referring to the sideways smiley faces and other characters made out of the ASCII character set, for example, :-P. These are often used in e-mail, ICQ, or other messaging systems, or when chatting in online gaming experiences.

Engine:

The core code that handles the most basic functionality of the game, but not including the code that governs specific gameplay functionality. Sometimes the engine is split up into the rendering engine, the sound engine, the behavior engine, and so forth. Each of these components can be considered to be part of the game s engine as a whole. Engines are typically more general than a particular game, which allows them to be reused for multiple different projects. However, some developers use the term engine to refer to the entirety of a game s source code. For example, id Software has licensed their Quake engine for use in a broad range of games, from Half-Life to Soldier of Fortune to Medal of Honor: Allied Assault .

Exploit:

An exploit is a technique a player may use in a game to become more successful more quickly than the designers had intended. Exploits are viewed by developers as bugs , and are typically fixed by patches when possible . It is important to differentiate an exploit, which gives a player unfair advancement, from an emergent behavior, which the designer may not have anticipated but which does not ruin the player s experience. Exploits should be fixed, while emergent solutions should be embraced.

Finite State Machine:

See State-Based AI .

First-Person Shooter:

The type of game exemplified by Doom , Half-Life, Unreal , Marathon , Halo, and Medal of Honor . In first-person shooters, the player s perspective of the world is from the first person and his objective is to shoot everything in sight, though some first-person shooters offer some subtle variations on this goal.

Flight Simulator:

Often shortened to flight sim, this is a type of game that attempts to model the flight of a real-world aircraft. The amount of realism involved varies from game to game; some games are extremely realistic and difficult, while others prevent the player from crashing entirely. Examples include Microsoft Flight Simulator , F-15 Strike Eagle , Flight Unlimited , and Hellcats Over the Pacific .

FMV:

See Full-Motion Video .

Focus:

A brief, three- to five- sentence description of the most important concepts guiding a game s development. Described in detail in Chapter 5, Focus.

FPS:

Depending on the context, this may refer to the first-person shooter genre of games or to the frames per second that the game s engine is currently rendering. See First-Person Shooter.

FSM:

Stands for finite state machine. See State-Based AI .

Full-Motion Video:

Any non-real -time graphics in a game that are displayed quickly in a sequential order to create a movie-like effect. Full-motion video can be of live actors, computer-generated environments, or a combination of the two.

Functional Specification:

The sister document to the technical specification, in that it describes how the game will function from the user s perspective, as opposed to how the programmer will implement that functionality. In game development, typically referred to as the design document. See also Design Document .

Fuzzy Logic:

A type of AI that introduces some degree of randomness into the decision making process. This means that, given the exact same inputs, an AI agent will make different decisions based on chance.

Game:

The Oxford Universal Dictionary includes a number of definitions for game. The definition we are most interested in for this book reads as follows: A diversion of the nature of a contest, played according to rules, and decided by superior skill, strength, or good fortune. To rephrase, a game presents an entertaining challenge to the player or players, a challenge which the player or players can understand and may be able to succeed at using their wits, dexterity, luck, or some combination thereof. To expand, in order for that challenge to be meaningful, the player must be presented with a number of interesting choices for how to succeed at the game, and those choices must be non-trivial. And in order for the challenge to be truly meaningful, the game must define the criterion for success. This excludes software toys such as SimCity from being games. Of course, one could write an entire book about the nature of a game at its purest level, but this is not that book.

Game Design:

The game design establishes the shape and formof the gameplay in a game. The game design may be communicated through a design document, or it may only exist in the head of the implementors of the game. See also Gameplay .

Game Designer:

The game designer is the person on a project who is responsible for establishing the form of the gameplay through the game design. See also Gameplay and Game Design.

Game Engine:

See Engine .

Game Flow:

The chain of events that make up the playing of a given game. A game can be said to flow between its action, exploration, puzzle-solving, and storytelling components. The proportional amount of time spent in each of these components and the pace at which the game takes place contributes to its overall flow.

Game Master:

In a pen and paper role-playing game, the Game Master is the player who governs the actions of all of the other players in the game-world. The Game Master often has also dreamt up the adventures that the players are going on, and continues to dynamically create this story as the players navigate through it.

Game Mechanic :

A specific way in which a part of the gameplay is implemented. For instance, the mechanic for doing an attack-jump in Crash Bandicoot is to hold down the down or crouch button while in mid-jump. The mechanic for sending a unit to a new location in WarCraft is to click on the unit in question with the left mouse button, move the pointer to the desired position on the map, and then click there with the right mouse button. The gameplay as a whole is made up of a number of different game mechanics combined together.

Game Minute:

A narrative description of how gameplay will proceed in a given situation in a game. These prose narratives are typically written before development on the game has begun, to give the development team an idea of how the game will play when it is complete. You will find a detailed discussion of game minutes in Chapter 17, Game Development Documentation.

Gameplay:

The gameplay is the component that distinguishes games from all other artistic mediums. The gameplay defines how players are able to interact with the game-world and how that game-world will react to their actions. One could consider the gameplay to be the degree and nature of a game s interactivity. Of course many different people have different definitions for gameplay, but as far as this book is concerned , gameplay does not include the game s story, graphics, sound, or music. This is easy to understand if one recalls that gameplay is what separates games from other artistic mediums; each of these components is found in literature, film, or theater. Gameplay also does not include the code used to make the game run, the game s engine, though that engine does necessarily implement the gameplay. The gameplay, however, could be implemented using a completely different engine while remaining identical.

Game-World:

This is the space in which a game takes place. In a board game such as The Settlers of Catan , the game-world is represented by the board the game takes place on. For a sports game, the game-world is the real-world but is limited to the extent of the field the game is played on. For a role-playing game, the game-world is maintained within the imaginations of the Game Master and the players. For a computer game, this is a virtual space that is stored in the computer s memory and that the players can view via the computer screen. The actions the player makes in a game are limited to the game-world, as are the reactions of either the game itself or the other players.

GM:

Depending on the context, see Gold Master or Game Master .

Go Live:

Term used for when a massively multi-player game is launched and players start playing it. See Live .

Going Gold:

The time when a team completes a game and is thereby able to create the gold master, which is sent to the duplicators. See also Gold Master .

Gold Candidate:

See Release Candidate .

Gold Master:

The version of the game, typically recorded onto gold CDs, that is going to be used by the duplicator to create copies of the actual shipping game. In other words, the final version of the game.

Graphical User Interface:

This is any communications method the player has of interacting with the computer that is primarily graphical in nature. For instance, the Macintosh has always had a graphical user interface, as opposed to the text-oriented one available in MS-DOS or UNIX. Games use GUIs for starting up new games, loading saved games, and choosing other options from the main menu, but also for communicating information to the player not readily apparent from their view of the game-world: the player character s health, currently equipped weapon, amount of ammo, number of lives, score, and so forth.

Griefing:

In a multi-player game, especially a massively multi-player online game, griefing is when players go out of their way to ruin the play experience of other gamers. This may be as simple as blocking a doorway so other players cannot travel through it, or it may be as mean-spirited as actually killing them. Griefing is different from simple competition, since griefers have little to gain by their actions beyond sadistic satisfaction.

GUI:

See Graphical User Interface .

Heads Up Display:

A type of graphical user interface that is overlaid on top of the player s game-world view. This may include the player character s health, a mini-map of the area, or radar of some sort, and typically communicates vital information to which the player must always have easy access. Heads up displays take their name from the displays used by jet fighter pilots, which constantly convey crucial flying information to those pilots while they are navigating the plane. See also Graphical User Interface.

High Concept:

The most primitive form of a game idea, high concept describes a game in the simplest terms. Unfortunately, high concept ideas have a bad reputation because of their tendency to describe games that are best not developed. For example, a high concept might attempt to merge disparate types of gameplay or setting into one game, without regard to whether those different ideas will work well together. An example might be making a first-person shooter with a turn-based strategy game, or a wargame that includes a golf simulator. In these unfortunate cases, a high concept is often synonymous with a bad concept.

HUD:

See Heads Up Display .

IF:

See Interactive Fiction .

IK:

See Inverse Kinematics .

Immersive:

When discussed in the context of games, an immersive game is one that tries to suck players into the world, making it as believable and consistent as possible, while giving the players as many choices as possible. Typical of an immersive game is a first-person viewpoint and a lack of gamey elements, such as blinking power-ups or obtrusive GUIs and HUDs.

Input/Output:

Often shortened to I/O, this refers to the systems a computer uses to allow the player to input information (typically a keyboard and a mouse) in combination with how it communicates information back out to the user (typically the monitor). In terms of computer games, the I/O refers to the controls with which the player manipulates the game and the way the game then communicates to the player the current nature of the game-world.

Interactive:

An interaction is when two systems, be they a human and a human, a human and a computer, or a computer and a computer, are mutually active in a given process. For instance, a television show is not interactive, since the television only outputs data and completely ignores whatever the user/audience does. A conversation between two people is interactive, however, since both parties listen to what the other has to say and will then say something related or in response to that. As another example, a strict lecture is not interactive since the lecturer reads a prepared speech without any input from the audience. A discussion group , however, is interactive, since the professor or leader of the discussion will answer the students questions and listen to and evaluate their ideas. Games are interactive since they allow both the player and the computer to determine the shape of that particular game. Computer games are not being especially interactive when they play long cut-scenes over which the player has no control.

Interactive Fiction:

A term originally coined by Infocom, interactive fiction is an alternate name for text adventures. Some people use interactive fiction to describe any games that use text to describe scenes and include a text parser, even if graphics are also included. See also Text Adventure .

Interactive Movie:

A term coined by those working in games who wish to call their profession something more glamorous than what it is. This is similar to how the comic book industry sometimes attempts to call some of its longer and more sophisticated works graphic novels . Typically, interactive movies involve more and longer cut-scenes than your average game. Unfortunately, the makers of so-called interactive movies typically add more movie than they do interactivity, resulting in works that are almost always not very good movies and lack the interactivity to be good games.

Inverse Kinematics:

An animation technique whereby a joint in a character s skeleton is moved to a desired location and the joints that depend on or are influenced by that joint are automatically moved to the correct location. For example, if animating a humanoid, the hand could be moved toward a door handle and the elbow and shoulder would automatically move to reasonable positions . See also Skeletal Animation .

I/O:

See Input/Output.

Isometric:

Isometric is defined to mean equality of measure, particularly in reference to drawing objects. If one were isometrically drawing a cube from a distance with one of the points of the cube pointing directly toward the viewer, the lines of the cube would all be of the same length and would not use any foreshortening. Games such as Civilization II , SimCity 3000 , and StarCraft are drawn isometrically. This allows a game to be drawn from a somewhat 3D overhead view, which can then be scrolled around in all directions, without actually needing to involve a 3D rendering engine. The perspective on the world is technically wrong, but players do not seem to mind. Also referred to as a three- quarters view of the game world. See also Three-Quarters View.

LAN:

An acronym for a Local Area Network. These networks typically consist of a small number of computers in a specific area networked to each other but not necessarily to the Internet or other networks.

LAN Party:

Held when a bunch of friends get together, bring their computers to one central location, and play multi-player games over them. Typically the fast ping times allow players to have much faster and more lag-free games than are available over the Internet or other long-distance networks.

Linear:

When the only way to get from point A to point B is via the line segment that connects them, we say that the movement is linear. Linear implies a lack of choice outside of a single dimension: forward or backward. In gaming, a linear game is one that does not give players much choice in what they do. For some games, linear may mean no choice at all, since backward is often not even an option.

Live:

A term used for when a multi-player online game is up and running, with users from the world at large playing it. The expression go live means the time when the game is released for the general public to start playing. The live team consists of the developers responsible for keeping the game running and updating its content once it has launched. Any MMP developer will tell you that the act of keeping a game live and working smoothly is as much work as developing it prior to launch.

Lone Wolf:

Term used to describe game developers who do practically everything themselves in the development of a game: the design, programming, art, sound, and writing. At the very least, a lone wolf developer must do all of the game s design and programming himself. A lone wolf does not typically develop commercially released software any more, though there are exceptions. For example, Chris Sawyer designed and programmed all of RollerCoaster Tycoon by himself, with a contractor completing the art to his specifications. Though he did not do the art himself, Sawyer can still be described as a lone wolf developer.

Massively Multi-Player:

Strictly defined, a multi-player game involving a very large number of people playing it at once, at least 100 or more. Typically such games are also persistent and played over the Internet. Ultima Online and EverQuest are examples of massively multi-player games. See also Multi-Player and Persistent .

Media:

Go out and buy Marshall McLuhan s Understanding Media . Read it. Come back only when you fully understand it.

Metagame:

According to Richard Garfield, creator of Magic: The Gathering , the metagame is how a game interfaces with life. This means what players take to and bring away from a particular playing of a game and how that impacts their subsequent playings of that game. This is particularly applicable to multi-player games. Take, for example, a game of Unreal Tournament on the Internet. If one player is known to play unethically through camping and other undesirable tactics, players will be likely to make a special effort to eliminate him in subsequent games. This means that the player may end up losing subsequent games because of his behavior in previous games. This interaction between the players from game to game is not part of the playing of the game itself, but is part of the metagame that the playing creates. For another example, in Magic: The Gathering the time a player spends preparing his deck before a game, though not part of the game itself, is part of the metagame.

Milestones:

A term often used in contracts between publishers and developers. A milestone is an agreement of how much work on a project will be done at a specific date, with the publisher only paying the developer when that milestone (usually in the form of a current build of the game) is delivered to the publisher.

MMOG:

Stands for Massively Multi-Player Online Game. See Massively Multi-Player.

MMORPG:

Short for Massively Multi-Player Online Role-Playing Game, such as Dark Age of Camelot , EverQuest , or Ultima Online . See Massively Multi-Player.

MMP:

See Massively Multi-Player.

Mod:

Short for modification, mods are user-created add-ons or changes to an existing game. Mods were popularized by id Software s open -architecture policy, which allowed players to make their own levels for Doom . Beyond levels, mods also often include new AI, new weapons, new art, or some combination of all three, potentially creating a radically altered gameplay experience from what was found in the original game.

MOO:

Stands for MUD, Object Oriented. See MUD.

MUD:

Originally stood for Multi-User Dungeon, but now can also stand for Multi-User Domain or Multi-User Dimension. MUDs resemble a text adventure with heavy RPG elements in their central play mechanics, with the important difference being that they take place in persistent, massively multi-player worlds . MUDs were set up and run by college students starting in the 1980s. Players of the games, when they reached a high enough experience level or rank, would become the creators of the games content for other, less experienced players to explore. The primary interest many players have in MUDs is the social component, preferring to chat with people they have never seen before to going on Dungeons & Dragons style adventures. In many ways, Ultima Online and subsequent MMORPGs are carefully regulated graphical MUDs. Another popular variant are MOOs, which stands for MUD, Object Oriented. MOOs are architected such that players are able to easily expand the game-world themselves. There are also MUSHes, which are Multi-User Shared Hallucinations. MUSHes tend to forgo typical MUD gameplay, which centers around accumulating stats and weapons, in favor of a more social, role-playing oriented experience. There are lots of other acronyms forMUDvariants, such as MUCKs and MUVEs, which I encourage readers to search out on the Internet if they are so inclined.

Multi-Player:

A game that involves more than one player. Today, this typically also means networked multi-player where each player has his own computer and competes with the other players over a network, such as the Internet.

MUSH:

Stands for Multi-User Shared Hallucination. See MUD.

Newbie:

Slang for someone who is new to something. In games, this means novice players who have just started playing a particular game. Often used to refer to players who have just joined an online game, such as a massively multi-player RPG. Newbies are often at an extreme disadvantage to the players who have been playing longer.

Non-Linear:

Obviously, the opposite of linear. In terms of gaming, this means that players are not locked into achieving different goals in a specific order or in achieving all of the goals they are presented with. Instead, players are able to move through the game in a variety of paths and can be successful in a variety of ways. Non- linearity leaves players with more choices to play the game their own way. See also Linear and On a Rail .

Non-Player Character:

Any character in a computer game that is not controlled by the player. Typically this refers to game-world characters that are not hostile to the player, such as townspeople in an RPG.

NPC:

See Non-Player Character .

NURBS:

Stands for non-uniformrational B-splines. A 3D graphics technique for creating curved surfaces, a detailed explanation of which should be sought out in a 3D graphics programming book.

On a Rail or On Rails:

A game is said to be on a rail when players are forced to move through the game in a very specific, carefully controlled way, as if they were locked onto a rail that ran through the game. Games that are said to be on a rail or on rails are very linear games. A specific type of game called a rail shooter is on rails to such an extent that the flight path of the player s vehicle is completely predetermined, and players are only able to shoot at targets as they pass by. Rebel Assault is an example of a rail shooter. See also Linear .

180 Degree Rule:

A film technique for cutting a scene that says that the camera must always stay on one side of a line that extends between the two centers of attention in the frame. If the camera never rotates anywhere outside of those 180 degrees, the audience will not become confused by the scene s cuts from character to character.

Online:

A game that is played online is run over any sort of a network, whether a LAN or the Internet. Typically online games are multi-player, and, since each player has his own machine and display, allows each player to have a blind-play experience, where other users cannot see what tactics he is using. This makes online games play significantly different than single system multi-player games.

Parser:

In gaming, often refers to the input method used by text adventures. A parser takes natural language words or sentences the player enters and translates them into commands that the game logic can understand. Parsers can become quite sophisticated while still failing to understand many of the sentences that players attempt to use as commands. Natural language processing is a major field of AI research, one that is still far from perfect, so it is no wonder that parsers have as much trouble as they do. A more modern usage of the term parser is in reference to the interpreter for a game s scripting language. See also Text Adventure .

Pathfinding:

This is the portion of the AI code that allows an agent to figure out how to get from one location to another in the game-world. Ideally, pathfinding allows the AI agent to avoid getting stuck on obstacles or other agents, yet pathfinding in many games is less than perfect. There are various algorithms, such as A*, that can be used for pathfinding, which may have different results in terms of efficiency and the quality of the paths generated, though that is a topic better explored in a book about programming. See also A* .

PC:

May refer either to a game s player character or to the Intel-based personal computer originally popularized by IBM and powered by MS-DOS. See also Player Character .

Persistent:

A persistent game is one that continues running and maintaining the state of the game-world regardless of whether a particular player is actively playing it or not. Often persistent games are also massively multi-player, and vice versa. MUDs were one of the first persistent games, while commercial products such as Ultima Online and EverQuest have made persistent games quite popular to mainstream gamers. See also MUD .

Pitch Document:

See Concept Document .

PK, PKing:

See Player Killer .

Place-Holder:

Typically refers to sound or art used in a game while it is in development but which the development team plans to replace before the game is released to the public.

Platform:

Often used to describe the different systems a game can be developed for. Popular gaming platforms past and present include the Apple II, Atari 800, Commodore 64, IBM PC, Commodore Amiga, Macintosh, Atari 2600, Nintendo Entertainment System, Sega Genesis, and Sony PlayStation.

Player Character:

This is the character the player controls in the game, such as Mario in Super Mario 64 , Lara Croft in Tomb Raider , or the space marine in Doom . This term is a holdover from pencil and paper RPGs such as Dungeons & Dragons .

Player Killer:

In multi-player games, players who go out of their way to ruthlessly kill other players. These are particularly problematic in games that are supposed to be more collaborative in nature, such as massively multi-player online RPGs.

Player Surrogate:

See Surrogate .

Player s Story:

This is the story the players create through their actions in playing the game. This will involve the clever techniques they used for succeeding at the game s challenges, whether it was where they positioned themselves to shoot and kill their enemies, how they laid the streets down to build up a city, or which plays they chose to win a football game. Some would be hesitant to call this a story, as it can often more resemble a simple chronology of events. However, the player s story is unique to that player s game experience, and is what he is most likely to remember and talk about with his friends .

Playtesting:

A term referring to the process of testing the gameplay of the game to see how well it plays. Playtesting is different from bug fixing or quality assurance in general since playtesting focuses on the performance of gameplay itself instead of general bug fixing. See Chapter 25, Playtesting.

Port/Porting:

The process of converting a game from one gaming platform to another, such as from the PC to the Macintosh, or from the Sony PlayStation to the Nintendo 64. Typically, games that are ported are completed on one system first, and only then brought over to the other system.

Power-Up :

A generic term that refers to any item in the game-world players may acquire to improve their abilities , either briefly or long-term. Typically used in action/adventure type games, a power-up may include a weapon, ammo, a key, a health pack, a jet pack, or money . Power-ups are often used to draw the player to explore certain locations, with the abilities granted by their acquisition conferring a generally positive reward on the player.

PR:

See Public Relations .

Pre-Rendered:

3D graphics that are rendered into 2D sprites or images before the player plays the game. Myst features pre-rendered 3D graphics, while Unreal features real-time 3D graphics. See also Real-Time 3D .

Proposal:

See Concept Document .

PSX:

An abbreviation for Sony s PlayStation console. Actually based on an early name for the system, the PlayStation X. Nonetheless, the abbreviation stuck. However, Sony does not like you calling their newer system the PSX2.

Public Relations:

A wing of the marketing department whose primary job is to hype a company s upcoming games in the press by readying press releases, screenshots, and other information. They also can be quite helpful in granting permission to use screenshots in books such as this one.

QA:

See Quality Assurance .

Quality Assurance:

This is the process of testing a game to make sure that it is bug-free and plays reasonably well. The quality assurance cycle or period is the time when a nearly complete project is extensively tested just prior to release. In large companies, the quality assurance department or team performs that testing.

Rail, On a:

See On a Rail.

Real-Time:

Anything that is computed or rendered for players while they wait, such as graphics and pathfinding. This differentiates something from being pre-computed before the actual gameplay is taking place. Can also differentiate a game from being turn-based. See also Turn-Based.

Real-Time Strategy:

A currently popular genre of games, including such titles as Command & Conquer , WarCraft , Total Annihilation , and Myth: The Fallen Lords . This term is typically emphasized to differentiate these RTS games from turn-based strategy games such as Civilization , X-Com: UFO Defense , and Alpha Centauri .

Real-Time 3D:

Describes 3D graphics that are rendered while the player is looking at them, so that as the player moves around the world, many different views of objects and configurations of the game-world can be generated on the fly. Unreal uses real-time 3D graphics while Myst uses pre-rendered 3D graphics. See also Pre-Rendered.

Release Candidate:

A build of the game the development team believes may be the one that can be shipped. A release candidate is generally tested for at least a few days, optimally a week or two, to determine if it is bug-free enough to be acceptable to the publisher. It is not uncommon for a particular product to go through five or more release candidates. See also Alpha and Beta .

Role-Playing Game:

Games based on the type of gameplay established by pencil and paper role-playing games such as Dungeons & Dragons . Those original noncomputer games were so titled because in them players took on the roles of characters of their own creation and guided them through a fantasy world. Much of the gameplay in RPGs depends on the players role-playing these characters who often had personalities different from their own. Ironically, most computer role-playing games often contain very little of the role-playing aspect of traditional RPGs, instead choosing to concentrate on the combat mechanics and fantasy setting.

RPG:

See Role-Playing Game .

RT3D:

See Real-Time 3D .

RTS:

See Real-Time Strategy .

Scripted:

In terms of a game, scripted typically refers to AI behaviors that are planned in advance to allow the AI agents to look clever in specific situations in a level. Scripted events play the same way every time a player plays a level. Half-Life used scripted events, sometimes combined with dynamic AI, to produce very impressive gameplay effects that gave the illusion of a very smart AI system.

Sim:

Short for simulator or simulation. See Simulation .

Simulation:

Typically, in games that are described as simulations, the primary goal of the game s designer is to model a real-life system accurately and realistically , instead of simply making the game as fun as possible. This system could be anything, such as an aircraft of some kind, a race car, or a city. Simulation can also refer to a type of game programming where, instead of hard-coding different outcomes to player input, various systems are created out of which responses emerge. For example, System Shock and Deus Ex are systems- or simulation-based action/RPGs.

Simulator:

See Simulation .

Skeletal Animation:

An alternative to vertex deformation for 3D animations. With a skeletal animation system, the game keeps track of an animating character s skeleton. The animation then controls this skeleton, moving the animating character s mesh to match the skeleton properly. A skeletal animation system has the advantage of causing animations to take up much less space than when they are animated using a technique such as vertex deformation, and often leads to superior looking animations. Furthermore, the skeleton can be controlled procedurally for inverse kinematics effects of various types. See also Vertex Deformation and Inverse Kinematics .

Skin:

In gaming, skin refers to the texture set being used on a 3D player character in a game like Quake III Arena , Unreal Tournament , or The Sims . Players will get to choose what skin they play the game with, either from the default collection that comes with the game or by making their own and importing it into the game.

SKU:

Stands for stock keeping unit or shelf keeping unit. It is the unique number associated with every bar code and used by stores to track their inventory. Each unique version of a game is sometimes referred to as a different SKU. If one game ships for different platforms, say Macintosh and PC, then each version is a separate SKU. Similarly, Thief and Thief Gold are two different SKUs, though they are practically the same game.

Software Toy:

A term coined by Will Wright of Maxis to describe that company s first product, SimCity . A software toy is quite similar to a game, except that it defines no criterion for success. Players are just left to play with the game as they wish without ever winning or losing. Yet players may make a software toy into a game by defining their own personal conditions for success. See also Game .

Split-Screen:

A technique whereby multiple players are allowed to play and/or compete on a single computer or console because the screen is split into (typically) two or four sections. Each section then displays the portion of the game-world relevant to each player playing the game. The disadvantage to split-screen gaming over online gaming is that all the players can see the screens of the other players. The advantage to split-screen gaming is that all the players play in close proximity to each other, allowing for a significantly more social experience.

State-Based AI:

A type of AI that uses states for each of its agents. States include actions such as idle, walking, attacking, and so forth. The AI then switches the agent from one state to another depending on the conditions of the game-world. May also be referred to as a finite state machine or FSM.

State Machine:

See State-Based AI .

Story Bible:

A document that contains all the information available about the story elements of the game-world. Story bibles can be quite large, especially when working with properties with established histories, such as the Star Trek or Ultima universes. These documents are usually used as reference works for the developers during the game s creation. Described in detail in Chapter 17, Game Development Documentation.

Surrogate:

A term used to describe the entity that the player controls in the game, also known as the player character or the player s avatar. See also Avatar and Player Character .

Suspension of Disbelief:

A mental state that players achieve when they are fully immersed in the game-world and briefly forget that they are playing a game at all. Naturally players will disbelieve what is happening on the screen, since it is projected on a flat screen, it does not look exactly like the real world, and players control their actions in it with a keyboard and mouse or a controller instead of their normal body movements. However, as with movies, the time comes when players make the subconscious decision to forget the inherent fake-ness of the presentation, to suspend their disbelief, and to start to believe that they really are great heroes or they really are in outer space or what have you. Maintaining players in that state for as long as possible is one of the primary goals of immersive games.

TDD:

See Technical Design Document .

Technical Design Document:

This document takes the gameplay as described in the design document and explains how that gameplay will be implemented in more technical, code-centered terms. As a result, this document is often used primarily by the programming team. This can take the form of one massive document that covers the whole project, or it can be a number of smaller documents about specific features. Described in detail in Chapter 17, Game Development Documentation.

Technical Specification:

Another name for the technical design document. See Technical Design Document.

Text Adventure:

Text adventures are devoid of graphics and describe the gameworld to the player exclusively through text. Players are then able to interact with the game-world by typing in natural language sentences in the imperative form, stating what they want their character to do next . The form was made extremely popular by Infocom in the early 1980s. See also Interactive Fiction .

Three-Quarters View:

Typically refers to games that have an isometric viewpoint. This view can be in any rendering system with an overhead view of the ground where the camera is oriented at a 45-degree angle from the plane of the ground. See also Isometric .

Turn-Based:

Any game where the computer waits for the player to act before proceeding with its own actions. Civilization , for instance, is a turn-based strategy game, while WarCraft is a real-time strategy game. For some non-computer game examples, chess is a turn-based game while football (soccer) is real-time. American football is a bizarre hybrid of real-time and turn-based gameplay.

Turn-Based Strategy:

See Turn-Based.

Vertex Deformation:

A 3D animation system where the individual vertices of a model are moved one by one to new positions for each frame of the animation. This is the simplest 3D animation method to code for, but has many disadvantages over a skeletal animation system. Sometimes also called keyframe animation. See also Skeletal Animation .

Virtual Reality:

Technically, virtual reality, or VR, refers to advanced world-simulation systems at a minimum involving the user wearing a set of goggles with a small monitor or display device in each eyepiece. This allows players to get a truly 3D, stereo-vision experience. Also, the VR headset allows the players to turn their heads and have their view of the virtual world change accordingly to match the new location at which they are looking. VR systems may also involve wearing gloves or full-body suits that detect the user s motion and translate that into motion in the virtual world. Because of this, VR allows for some of the most immersive virtual environments possible. Virtual reality is one of the most commonly misused terms in all of computer game parlance. Many game developers with inflated senses of what they are doing will refer to their RT3D first-person games as VR when, since they do not involve headsets, they are really nothing of the kind. Marketing people are particularly fond of misusing and abusing this term.

VR:

See Virtual Reality .

Wargame:

When used in reference to computer games, wargame typically refers to strategy-oriented games that employ gameplay based on pen and paper or board wargames such as those made by Avalon Hill. Computer wargames almost always simulate historic battles , typically feature hexagon-based play-fields, and use turn-based gameplay. Games that are set in historical wars but are not strategic in nature are not generally referred to as wargames. Classic examples of computer wargames include Kampfgruppe and Eastern Front (1941), while more modern examples include Panzer General and Close Combat .