Game Development Reference
In-Depth Information
consequences
Dynamic friction is a good way to counter positive feedback created by engine pat-
terns. Dynamic friction adds a negative feedback loop to the game system.
implementation
There are several ways of implementing dynamic feedback. An important consid-
eration is the choice of the element that causes the consumption rate to change.
In general, this can be either the amount of available energy itself, the number of
upgrades to a
dynamic engine
or a
converter engine
, or the player's progress toward a
goal. When the amount of available energy changes the friction, the negative feed-
back tends to be fast. When progress or production power is the cause, the feedback
is more indirect and probably slower.
When dynamic friction is used to counter a positive feedback loop, it is important
to consider the difference in characteristics of the positive feedback loop and the
negative feedback loop implemented through the dynamic friction. When the char-
acteristics are similar (equally fast, equally durable, and so on), the effect is far more
stable than when the differences are large. For example, when a slow and durable
dynamic friction is acting against a fast but nondurable positive feedback that ini-
tially yields a good return, players will initially make a lot of progress but might
suffer in the long run. Fast positive feedback and slow negative feedback seems to be
the most frequently encountered combination.
examples
The mechanics of tower defense games typically revolve around a dynamic drain
on the player's life points caused by enemies that the player must keep under con-
trol by building towers (
Figure B.7
). In this case, the goal of the game is to prevent
dynamic friction from taking effect. In real tower defense games, placing the right
types of towers involves a strategy that is omitted from this diagram.
FIGURe b.7
dynamic friction in
tower defense games
