I'm reading a book that talks about relational databases and
object-oriented databases. First off, racing and flying simulators use a
database, correct? How does this get implemented? Is it just used to call
on the capabilities of a plane or car or is it used in the realtime
calculations of the program? And finally, what type is used, relational or
object-oriented? Is one faster than the other?
Bill
Bill,
If you really want to get into the nuts and bolts of a flight
simulator, check out the flight gear project: www.flightgear.org. We
are working on an open-source flight sim and have made some very good
progress to date, but have a lot of work left to go. You can always
download and try running the latest versions ...
"Bill Hutchinson" <[email hidden]> writes:
> I'm reading a book that talks about relational databases and
> object-oriented databases. First off, racing and flying simulators
> use a database, correct?
Modern simulators have to manage a ton of data. For the flight gear
project, the scenery for the entire world consumes about 2Gb right
now. As the size of the data you are managing goes up, using a
database begins to make more and more sense.
> How does this get implemented?
I'm sure the answer will be wildly different for every simulator
... and even for different types of data within a single simulator.
I've everything from ascii-text files to
use-the-file-system-as-your-database to real databases. It depends a
lot on the size and nature of the particular data you are managing.
> Is it just used to call on the capabilities of a plane or car or is
> it used in the realtime calculations of the program?
If you are talking about the properties of a vehicle, then yes, these
could be stored in a database, or in a simple ascii file, or many
other ways I suppose. In general, you would load in the properties of
the vehicle once and then pass these to the physics routines to
actually simulate the vehicle ... you wouldn't need to load vehicle
property data every frame.
> And finally, what type is used, relational or object-oriented? Is
> one faster than the other?
It all depends on the nature of your data, and how you are accessing
it. Often, simpler is better.
Curt.
--
Curtis Olson University of MN, ME Dept. Flight Gear Project
Twin Cities [email hidden] [email hidden]
Minnesota http://www.menet.umn.edu/~curt http://www.flightgear.org
it is possible to hold the physics data in a database but i think you'll
find a lot of racing games hold most of their data in flat file format. The
main exception would be the RTS category that have to hold a lot of
information about units ammunition etc in those cases a database would be
faster and easier to keep track of.
As to the faster of the two im not sure ... however it would depend on the
amount of data to be held. hmmm there is no reason why a relational database
couldnt be accessed using object-oriented code, not sure what you meant
there.
I'm sure there are more qualified peeps with the answers. you might also
want to try the comp.games.development.* news groups for these questions
cheers
shane
