Game Development Reference
In-Depth Information
3
Converting Behaviors
to Algorithms
Different fields of work have their tools. Some are the typical physical tools
such as the hammers and nails that carpenters use. Some are more concep-
tual such as a standard business process in the business world. In the game
industry, artists have their standard tools as well. Some are physical such as model-
ing and animation software packages, and some are conceptual such as the idea of
using the texture-mapped triangle. In my view, however, there is an intermediary
between a pure tool and the end product.
A writer, for example, uses tools ranging from the word processor to pen and
paper to the venerable quill pen and stone tablet. There are more abstract tools as well.
The formalized rules of sentence structure and verb conjugation provide guidelines
for what the reader expects from the writer's method of delivery. The words he uses,
however—the fine points of the
language
he chooses to express his thoughts—are
the intermediary. It is through the selection of words that the idea is articulated.
A classical artist uses brushes as his tools of choice. At first glance, one would
label the paints as tools, too. I would contend that the paints are more of a
language
of expression—the liaison between the pure tool and the end product. There are
suggestions as to what paints to blend to achieve certain colors and the proper way
to mix them for various effects. However, it is up to the artist to decide how to
achieve what he is attempting to portray. The paints are what allow the expression
of creativity. They are what give variety and depth of character to the work.
Game artificial intelligence (AI) has its standard toolbox. Many algorithms and
data structures are repeated over and over throughout all the games on the shelf. In
fact, given the wide range of in-game behaviors that are exhibited, there are actually
startlingly few methods on the list. In this case, a technique such as A*, a behavior
tree, a state machine, or even a planning algorithm is a raw tool. Left to their own
devices, however, those algorithms don't create behavior any more than words
alone create a soliloquy or paints alone create an image of a supine swine. The nuance
isn't in the method itself; the depth of behavior comes from the data that is inserted
into the algorithm.
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