Game Development Reference
In-Depth Information
One more number set is needed to complete the table. Use 96, 36, 18, 48, and 12. The
first usage number of 96 is high enough to be in the 96-100 range for the “10�? Look
Sensitivity value. This marks the first time that value appears in the table. Moving
through the rest of the numbers, the 36 puts a No in the Invert Thumbstick column,
18 corresponds to Controller Vibration = Yes, 48 is in the range for Invert Flight
Control = No, and 12 completes the final test row with a Yes for Auto-Center. Figure
12.14 shows all six Cleanroom combinatorial test cases.
Figure 12.14
Completed Advanced Controls Cleanroom combinatorial table.
Your keen testing eye should have noticed that Look Sensitivity = 1 was never gener-
ated for this set of tests. That is a function of its relatively low probability (10%), the
low number of test cases that you produced, and the particular random number set
that was the basis for selecting the values for table. In fact, if you stopped generating
tests after five test cases instead of six, the default value of “3�? would have been the
only value for Look Sensitivity that appeared in the table. This should not be consid-
ered a problem for a table of this size. If a value has a 5% or higher usage probability
and you don't see it at all in a test set of 100 or more tests, then you may suspect that
something is wrong with either your value selection process or your random number
generation.
Also notice that some values appear more frequently or less frequently than their
usage probability would suggest. Auto-Center = Yes only has a 30% usage for the
Casual profile, but it appears in 67% (4/6) of the tests generated. This is mainly due
to the low number of tests created for this table. With a test set of 50 or more you
should see a better match between a value's usage probability and its frequency in the
test set.
Just to reinforce the fact that the Cleanroom combinatorial table method doesn't
guarantee it will provide all test value pairs that are required for a pairwise combina-
torial table, confirm that the pair Controller Vibration = No and Auto-Center = No is
absent from Figure 12.14. Now take a moment to see which other missing pairs you
can find.
