Game Development Reference
In-Depth Information
TERMINOLOGY ISSUES
The term
button
is unfortunately overloaded, because it sometimes refers to a button on
an input device that the player can physically press and at other times it refers to a visual
element on the screen that the player can click with the mouse. In order to disambiguate
the two, this chapter always refers to physical buttons on an input device as
controller
buttons
and those on the screen, activated by the mouse, as
screen buttons
.
Keys
refers
to keys on a computer keyboard. The term
key
is interchangeable with
controller button
because they both transmit the same type of data.
Menus and screen buttons appear on the screen as visual elements, but clicking them
with the mouse sends a message to the internals of the game, which makes them control
elements as well. Furthermore, the appearance of a screen button may change in
response to a click, making it a mechanism for giving information as well as for exercis-
ing control. Your experience with computers should allow you to tell from context what
these terms refer to when you encounter them in this text.
Any discussion of user interface design runs into a chicken-and-egg problem: You
can't learn how to design a good UI without already knowing the names of com-
mon visual elements such as power bars and gauges, and this chapter can't introduce
the common visual elements without making references to how they're used. So, to
address the most critical information first, we'll start with the principles of inter-
face design. If you encounter a reference to an interface element you've never heard
of, see the section “Visual Elements” later in the chapter for an explanation.
Dozens, perhaps hundreds, of published topics address user interface design, and
this chapter does not try to duplicate all that material. The following sections con-
centrate specifically on user interfaces for games, how they interact with the game's
mechanics, and how they create the entertainment experience for the player. To
read more about user interfaces in general, see
The Elements of User Experience
by
Jesse James Garrett (Garrett, 2003).
A game's user interface plays a more complex role than does the UI of most other
kinds of programs. Most computer programs are tools, so their interfaces allow the
user to enter and create data, to control processes, and to see the results. A video
game, on the other hand, exists to entertain and, although its user interface must
be easy to learn and use, it doesn't tell the player everything that's happening
inside the game, nor does it give the player maximum control over the game. It
mediates between the internals and the player, creating an experience for the
player that feels to him like gameplay and storytelling.
