The Vision of a RealWorld Simulator - Programming GPS and OpenStreetMap Applications with Java - page 20

2.6 Real-Object Application Framework (ROAF)

While a RO can be generalized as an actor, the ROApp represents the
scenario to act and interact in. Each RO{ROApp combination denes a
special domain, a specified area, and a set of rules.
Imagine looking at a city map where you can watch the movement of
buses. This ROApp could be realized by simply providing the time sched-
ules for each vehicle, which report the vehicle's location when requested by
the ROApp. The vehicles, being ROs, wouldn't have any degree of freedom
since the bus driver has to follow a schedule.
One might also consider providing a ROApp for the city's subway sys-
tem. The city map can be reused, although the subways would follow their
own path rather than the street map from the previous city map. Both

ROApps are pretty simple and partially overlap.
The next step would be to merge the two ROApps. Merging public buses
with public subways sounds pretty simple, but the more you think about
it the more rules you'll need.

A real-object application framework is defined by the laws common to
all ROApps, which should be coded in a roaf library. Different ROApps
(responsible for their ROs) can be overlaid, if they (partially) conform to
the ROAF standard.

Definition 2.3
Initial ROAF
vision

Many ROApps can be combined in one real-world

simulation.

Technically a ROAF is a kind of a server farm (or cloud).

2.7 Science Fiction

The ROAF vision was derived from the object-oriented paradigm in soft-
ware development. This might be feasible for a programming class, but
it is not sucient to attract a user to the project. The word \vision"
probably raises a much more exciting expectation, as for example in the
context of science fiction. Of course, a science-fiction movie extrapolates
from current technology to maintain credibility. So, before you put the
book aside here's another way to look at the ROAF vision|simply replace
ROAF with \Matrix" and think of the movie! 1
The lm poses the question \What is real?" Is everything we sense real
or is this perceived reality only created by electrical signals in the brain?
We will not discuss how to hard-wire our senses to a computer, although
this may become reality one day. The more interesting aspect of The

1 TheMatrixby Laurence and Andrew Wachowski, 1999.