Of Kangaroos and Object-Oriented Programming.
Posted: Sat May 20, 2006 10:06 pm
Thought you all might like this, my profressor in our intro computer science Object Oriented Programming class had this to say about code reuse:
The reuse of some object-oriented code has caused tactical headaches for
Australia's armed forces. As virtual reality simulators assume larger
roles in helicopter combat training , programmers have gone to great
lengths to increase the realism of the their scenarios, including
detailed landscapes and -- in the case of the Northern Territory's
Operation Phoenix -- herds of kangaroos (since groups of disturbed
animals might well give away a helicopters position).
The head of the Defense Science and Technology Organization's Land
Operations/Simulations division reportedly instructed developers to
model the local marsupials' movements and reaction to helicopters.
Being efficient programmers, they just re-appropriated some code
originally used to model infantry detachments reactions under the same
stimuli, changed the mapped icon from a soldier to a kangaroo, and
increased the figures' speed of movement.
Eager to demonstrate their flying skills for some visiting American
pilots, the hotshot Aussies "buzzed" the virtual kangaroos in low flight
during a simulation. The kangaroos scattered, as predicted, and the
Americans nodded appreciatively . . . and then did a double-take as the
kangaroos reappeared from behind a hill and launched a barrage of
stinger missiles at the hapless helicopter. (Apparently the programmers
had forgotten the remove "that" part of the infantry coding).
The lesson? Objects are defined with certain attributes, and any new
object defined in terms of the old one inherits all the attributes. The
embarrassed programmers had learned to be careful when reusing
object-oriented code, and the Yanks left with the utmost respect for the
Australian wildlife.
Simulator supervisors report that pilots from that point onwards have
strictly avoided kangaroos, just as they were meant to.
