Terminology
What do you think of when you see the word isometric? Tile-based? Avatar? Don't worry, there's no need to run for your dictionary. Entering the world of game development, you'll find that, as with all specialized fields, a lot of descriptive terms are commonly used when talking about games. It is important to understand, or at least have some idea of, what a word means when you run across it in this book. Most of these terms will be described in more detail in later chapters, but here's an overview to get you started.
Game Views
A game view is the player's perspective in the game. Is the player seeing everything through a character's eyes, or from above? Each of the possible views has its own name. The game view is sometimes referred to as the point of view.
3DThis generic term encompasses almost all possible views of any game that is not two-dimensional. Specific types of popular 3D views have their own terms (listed next). Almost all of the most popular store-bought computer games (such as Unreal Tournament, at right) use a 3D view. While we will not be using a generic 3D engine in this book, we will be using a specific 3D view, isometric (see below).
ChaseThis type of 3D camera view is popular in some sports games, like hockey and football. The camera (that is, what you see) follows the character or the action and may even swing around to get the best angle. This game view will not be used at all in this book.
First personThis view is what it would be like to see the environment from the character's point of view. First- person-view games are very popular in shoot-'em-up games like Quake, Half-Life, and Unreal Tournament. We will not use this view in any games in this book.
IsometricThis is one of the most widely used 3D views. You may have seen this view in games such as Diablo (at right) or Electrotank's Mini Golf. It is used frequently because with this view you can get away with graphical tricks that reduce the work of both the programmer and the graphic artist. We will discuss this in detail in Chapter 8, "The Isometric Worldview." any view that isn't either first person or through another character's eyes. Most of the views listed here, such as isometric, are third-person views.
SideThis type of view lets you see what is happening from the sidelines. You may have seen this view in games such as Super Mario Brothers or Donkey Kong. Side views are very popular in platform games and are almost always two-dimensional. This view is used in Ice World, shown at left and dissected in Chapter 15.
Third personThis term describes any view that isn't either first person or through another character's eyes. Most of the views listed here, such as isometric, are third-person views.
Top downThe top-down view shows you the game area as seen from above, the way a bird would see it. This view is popular for games like the original Zelda, and for many puzzle games like Minesweeper. At right, of course, is Pac-Man.
General Terms
Here are some commonly used game-development terms whose meanings you should be aware of.
AlgorithmAn algorithm is a logical process by which a problem can be solved or a decision made. An algorithm can be represented in a programming language, but it is more abstract than that. For instance, you can create a process to sort a list of names. This process is an algorithm and can be expressed with ActionScript or any other programming language.
Artificial intelligence (AI)This refers to an algorithm or set of algorithms that can make decisions in a logical way. For example, the AI routine for a bad guy in a game might let him figure out how to find you. Another use of AI is to have a maze or puzzle solved automatically.
AvatarSometimes chat rooms are designed to enable people in those rooms to have graphical representations. These are called avatars, and the chat is often referred to as an avatar-chat.
Collision detection Also called hit detection, collision detection is the act of noting the intersection of two objects. This can be something as simple as determining if the mouse is over a button or as complicated as detecting the overlap of two moving objects.
Collision reactionThis is what happens after a collision has been detected. The term is usually used when talking about physical reactions, such as two billiard balls colliding and moving apart, or a ball bouncing off the ground.
ConsoleA computer designed for the sole purpose of playing video games. Among the console manufacturers are Nintendo and Sega.
MapAn area that defines the world of the game.
Real-timeUnlike turn-based games, in real-time games you can make a move whenever you like.
RenderTo draw an object to the screen. This term is most often used in reference to 3D games: The 3D engine calculates where a projectile should be, and then renders it.
Source codeAlso known as source, source code is the original work created by a developer. Source code is compiled, or published, into a new file. This compiled file is what users will see, not the source itself. In Flash, the source is a .fla (or FLA) file, and its published version is a .swf (or SWF) file. The .swf file contains only a fraction of the information of in the .fla file. This serves to protect the author's work so that another person cannot take the source. This book's accompanying CD-ROM contains the source for many games.
Turn-basedThis refers to a restriction on when you, the game player, can make a move. For instance, chess is a turn-based game; rather than make a move whenever you want, you must wait for your turn. Many multiplayer games are set up this way, as we will see later in the book.
Vector graphicsNotable for their small file sizes and scalability, vector graphics are defined by sets of mathematical points. Flash uses this graphics format to great advantage.
WorldThe environment of the game.