[Flightgear-devel] Traffic 2020: Towards a new Development Model for FlightGear AI Traffic

[Durk T. <dur...@gm...>]

Hi Everyone,



After a long break, I feel the time is right for picking up where I left
off in early 2012: The continued development of the FlightGear AI Traffic
system. After a couple of years of intense involvement, development came to
quite a sudden halt after my day job responsibilities had to take
precedence. I’ve been very reluctant to pick up the pace again afterwards,
because I’ve been in much doubt whether to continue with the existing code
base or to restart from scratch.



To summarize, in the current code base, world wide AI Traffic is controlled
from an aircraft and flight information database, known as the Traffic
Manager. Whenever an aircraft is sufficiently close to the user’s aircraft,
a more detailed simulation is set up using the AIModels code. Currently,
the user controlled aircraft can interact with the AI generated flights in
a very limited fashion.



Although I am willing to, and probably will continue to develop the current
code base, I’m becoming aware of a number of severe limitations of the
current approach and therefore I’ve decided that it is probably a much
better idea to start developing something new from scratch. So my main
focus will probably be on developing a new system, I will probably continue
to devote some time to maintain and improve the existing code base until
the new code base takes can support the current functionality. More
specifically, I’m aware of the following fundamental limitations in the
current code base:

·      AI Traffic is not synchronized across multiple instances of
FlightGear

·      Unclear distribution of labor between the AIModels, ATC, and Traffic
Manager subsystems

·      A single set of (hard coded) traffic rules may work well at one
airport, but fail miserably at another one.

·      The development cycle is slow due to the requirement to recompile,
restart and wait until specific conditions are met.

·      The currently huge traffic database results in slow updating of all
Traffic Manager controlled aircraft, resulting in slow and inconsistent
initializations



To eliminate these problems, I’m proposing to slowly deprecate the current
approach, in favor of a more distributed approach. The idea is to write a
standalone program that is interacting with the FlightGear multiplayer
system. I won’t go into details yet, but the general idea is that this new
program can either transmit AI traffic data via a multiplayer servers, or
that it directly mimics communicates with FlightGear by acting as a
multiplayer server itself. I still need to work out the details, but the
general idea is that the new traffic generator will receive positional
information from FlightGear, and in exchange generate traffic information
for a small radius surrounding the user-controlled aircraft.



At this stage, my ideas are still in a relatively rough stage, but I think
it’s time to start working on it, as the inspiration I regained at
FSWeekend is still fresh. This is why I’m posting a rough outline of my
current ideas here.


Question #1 is: What would the best approach to add this to the git
repository: As a new target within the existing FlightGear git repository,
or as a new git repository within the FlightGear project?


Comments are welcome.



Cheers,

Durk