Game Development Reference
In-Depth Information
make sure that either the powerful NPC gets over his snit after a while or there's
some other way for the player to obtain the information.)
Figure 7.5
(on the following page) illustrates a brief conversation in which the
player is acting as a police detective, interviewing someone who may have wit-
nessed (or possibly committed) a crime. The conversation begins at the first menu,
and in that menu the player has a choice of four approaches to the witness: polite,
neutral, direct, or accusatory. Each approach produces a response from the witness,
which then leads on to another menu of things for the player to say. Each menu
has its own name.
In this example, the witness is rather uncouth, but is prepared to help the player as
long as the player is not too hostile to him. If the player takes a strongly aggressive
approach, the witness demands to see a lawyer, which ends the conversation. In
this case, the player will not learn some of the information that the witness has, so
the player will either have to re-interview the witness later, or find it out some
other way.
Figure 7.5 includes several features that are particularly worth noting:
Not all the menus in the figure let the player ask the same question in different
tones. Some give the player a choice of questions to ask about different subjects.
The menu “Ask About Evidence,” for example, lets the player ask about gunshots, a
car, or a man in jogging clothes. If the witness doesn't know anything about one of
these subjects, the arrow leads back to the same menu again so the player can ask
about a different subject.
Although all the witness responses in the menu “About the Car” lead to the
same place (the “Follow-Up” menu), each one still provides the player with some
different information.
Not all questions produce unique answers. In the “Time of Bar Visit” menu, the
polite and neutral approaches both elicit the same answer from the witness. This is
perfectly allowable if there's no particular reason to differentiate them.
Finally, note that in Figure 7.5, the maximum number of exchanges the player can
have, without repetition, is eight. As with branching stories, if the menus continue
to branch without folding back, you will soon get a combinatorial explosion of
menus. In practice, they frequently converge, or link back to previous menus.
Unfortunately, there is no industry standard system of notation or scripting for
designing dialog trees. Instead of creating a diagram with arrows as in Figure 7.5, you
may find it easier to write your dialog in a text file, and instead of drawing arrows,
simply write “Go to Menu [menu name]” to indicate which menu should follow a
given response. If such factors will affect your dialog, you should sit down with
your programmers and devise a system of notation that will be easy for you to cre-
ate and easy for them to understand; they have to understand all the factors and
when those factors come into play so they can write the software that actually
implements the system.
