Game Development Reference
Figure 12.20 Casual player usage table for Unlocked Item TFD flows.
Generate your Cleanroom tests from the flow usage table similar to the way you do
when the flow usage is on the diagram. The only difference is the extra step to look up
the flow's range in the table. If you are creating an automated process or tool to con-
struct TFD Cleanroom paths, this table could be stored in a database or exported to a
Admittedly, keeping track of flow usage in a table presents some problems. Because
the flow numbering does not have to be related to the way flows appear on the dia-
gram, it takes a little more work to identify the flows coming from each individual
state. For example, the flows coming out from NoPointsItemLocked —13 and 14—are at
opposite ends of the flow list. This wrinkle can become more of a problem when many
flows are added, moved, or removed to adapt to changes in the game software. Just be
careful and check your numbers when you are faced with this situation.
Inverted usage can be applied when you want to emphasize the less frequently used
functions and behaviors in the game. This creates a usage model that might reflect
how the game would be used by people trying to find ways to exploit or intentionally
crash the game for their own benefit. It also helps draw out defects that escaped ear-
lier detection because of the very fact that the game is rarely, if ever, expected to be
used in this way.