Game Development Reference

In-Depth Information

personalities. This equation is known variously as a fitness function or an eva-

luation function, and we will see it again in future chapters. Here the function can

be thought of as a measure of how well each occupation fits the likes of each

character.

The simulation starts a person with 10 days worth of wages in cash and runs for

1,000 work days. Each day, the simulation asks the person to pick an occupation

from the seven available. This decision will be influenced by the amount of

available cash and the person's particular way of evaluating choices. The simu-

lation will not allow the person to pick an occupation unless he or she has at least

twice the cost of the particular occupation in cash. If the person picks a different

job than the day before, the simulation outputs the results from the prior

occupation. Then the simulation takes the selected job and randomly determines

success or failure according to the odds. It deducts costs and applies gains or

losses to the person's cash. At the end of the day, the simulation deducts living

expenses based on the person's cash. The simulation brackets people as rich,

doing okay, poor, and almost broke with commensurate expense levels. People

who have negative cash are declared bankrupt, and their cash is mercifully reset

to zero.

There are seven occupations available to our simulated people. An occupation

carries a name and four items of numerical data:

n
The probability that the simulated person will succeed at the job on any

given day, denoted as P. The probability value is given as a percent, such

as 99.0 percent, but is stored as a decimal, as in 0.99.

n
The fixed cost of each attempt at participating in the occupation, denoted

as C. This cost is spent every time the simulated person attempts the

occupation, whether he or she succeeds or not.

n
The financial gain that the simulated player receives when he or she

succeeds at an occupation. Gain is denoted as G.

n
The financial loss the player incurs when he or she fails an attempted

occupation. The potential loss is denoted as L.