The in-game graphical user interface (GUI) is of critical importance to your game,
and therefore it should be described in detail in the Game Mechanics section. You
should describe any data that is overlaid on the depiction of the game-world, such as, for
an action game, the players’ health or other statistics needed during gameplay. The GUI
section should also cover any other GUIs that are part of gameplay, such as what play-
ers see when their surrogate becomes involved in a conversation or when managing
inventory. Describing the graphical interface is even more important for games like
Alpha CentauriorThe Sims, which include many different GUIs and in which players
constantly use the GUI to play the game. The descriptions of these GUIs can either all
be included in one part of the Game Mechanics section, or can be detailed during the
description of the system to which they are relevant. Remember that you want your
design document to be as reader-friendly as possible. If the art director is looking for
the different GUIs that need to be created and they are scattered throughout the Game
Mechanics section, some may be missed. On the other hand, a programmer might pre-
fer to find the GUI for a particular system included with the description of that system.
You need to decide which approach is in the best interest of your document and the pro-
ject. In the Game Mechanics section, you want to describe only the GUIs that are used
in the game and are therefore relevant to gameplay. Any of the front-end GUIs used
when players are starting a new game or loading an old one are not really part of the
gameplay. As such, the front-end GUIs should be separated into the System Menus sec-
tion, which I discuss later in this chapter.
It is easy to assume a lot when writing a Game Mechanics section, but a good
designer will avoid assuming anything. For instance, a designer may be working on a
first-person shooter in theQuakemold. She may make the assumption that when play-
ers run over an object, their character will automatically pick it up. The designer has
played so many first-person shooters that it is totally obvious to her that this is how she
wants it to work. But if she fails to write it down in the document, the programming
team may assume it will function some other way, copying their own favorite game. Do
not assume that the same gameplay components that are obvious to you will be obvious
to whoever is reading your document. Spell everything out explicitly so there is no
room for confusion.
You can almost think of the Game Mechanics section as an extremely detailed first
pass on the manual. You are describing in intense detail how players will accomplish
every different action in the game-world — what commands players will use and what
the results of those commands will be. If you are writing your game design document as
a journalist might write a news story, in the Game Mechanics section you should be
concerned with the “what” and “how” — what players do in your game and how they do
it. Later in the document, you will get to the “where,” “when,” and “why.”
Artificial Intelligence...........................
If the Game Mechanics section describes how players can interact with the
game-world, then the Artificial Intelligence section documents how the world will react
to the players’ actions. How will the opponents that players face in the game-world
behave? What will they do in which situations? This section may also describe how the
game-world behaves when players are not doing anything. For instance, it could discuss
ambient behaviors such as how townspeople go about their daily business.
366 Chapter 19: The Design Document