Hello, Algorithm used in recent flight games to play at many peoples on same server with few errors and few data transmission rate can perhaps be used:
Data send contain the position, velocity, attitude etc, but this information is not send often. In an other part of data send, are informations source of a change in the attitude of the plane, i.e input data of the FDM Engine. And those inputs are only send when it's value change. This allow a very low debit data, and so few space used on disk. to playback, you update some times the state of the FDM engine with the full list of state variable, and then you send some time new input to the FDM engine. This should replay the flight recorded. The frequency of the recording of the full state of the FDM can be adjusted regarding some parameters. (big variations, personal preferences... ) Just an idea ... On Tue, 2004-08-24 at 22:28, Olivier Soussiel wrote: > For a real flight playback, if attitude accuracy is not so important, only > GPS position data (one shot every second) is enought for a smooth FG > playback (if no acrobatics have been perform...). > > I think this playback function could be a nice for the debriefing of Flight > Intructors who let their students for their first solo country flight. Spy > on board... > > > ----- Original Message ----- > From: "Roberto Manca" <[EMAIL PROTECTED]> > To: "FlightGear developers discussions" <[EMAIL PROTECTED]> > Sent: Tuesday, August 24, 2004 3:11 PM > Subject: Re: [Flightgear-devel] Re: Bypass FG Physics and Draw > > > > While the idea is correct in principle, what you said > > it is not so straightforward. > > > > I've realised a flight recorder and a flight player > > for Flightgear for my thesis so I played around with > > few ideas. Basically I developed a virtual cockpit in > > a distributed environment that uses Flightgear to have > > some 'meaningful' flight data. I had to test different > > configurations so I needed to use always the same data > > that is to fly always the same flight. > > > > My experience is that it's very difficult to > > synchronise Flightgear with an > > initial-position-and-flight-command approach since the > > only cross-platform means of communication available > > is the socket. You always end up with a time shifting > > of the packets that produces a space shifting of the > > flight. Therefore sometimes you try to manouevre into > > a mountain while you did't in the original flight. > > Now what i've done is to record, through a socket, all > > the flight at an accettable frame rate onto a file by > > using the native-fdm data structure. (this is the > > recorder). Then I wrote a player that reads the file > > and sends the data over to Flightgear (previously set > > up with the external-fdm option). It works quite well > > apart from some adjustment in the speed of replay you > > need to experiment with. > > > > Roberto > > > > --- Harald JOHNSEN <[EMAIL PROTECTED]> ha scritto: > > > [EMAIL PROTECTED] wrote: > > > > > > > Does this mean that we would have the ability to > > > save and load flight > > > > data so as to reproduce, say, a taxi, take off, > > > pattern and landing at > > > > KSFO or another airport automatically (i.e., as a > > > demo or as a > > > > training exercise). Perhaps a short flight around > > > the SF area also > > > > showing off the new scenery? > > > > > > > > Could we ship such flights around scenic areas > > > (Mount Ranier, Crater > > > > Lake, the Grand Canyon) for new users in the base > > > package or as > > > > downloadables off of flightgear.org? > > > > > > > > How big would such files be? How much data needs > > > to be kept, how much > > > > can be calculated on the fly? Do weather > > > conditions need to be saved > > > > also? > > > > > > > > Would flights around scenic areas be done better > > > as flight plans with > > > > waypoints or tied into this new playback method > > > somehow? > > > > > > > > Can this playback tool be used as a training > > > method for new simulator > > > > pilots? > > > > > > > > If we are not saving a real recorded flight, > > > perhaps we can use a > > > > similar method to extract either entire flights or > > > the last XX number > > > > of seconds of a flight to save to disk for later > > > replay? > > > > > > > > MS FlightSimulator has an extensive tutorial that > > > involves pre-saved > > > > flights which the users can break into at certain > > > points in the > > > > flights. How difficult would it be to add > > > something similar to FG and > > > > where would one begin (if no one is already > > > working on something like > > > > this). > > > > > > > > Thanks! > > > > > > > > Ima > > > > > > > > > > > > _______________________________________________ > > > > Flightgear-devel mailing list > > > > [EMAIL PROTECTED] > > > > > > > > > http://mail.flightgear.org/mailman/listinfo/flightgear-devel > > > > 2f585eeea02e2c79d7b1d8c4963bae2d > > > > > > > I think that the ability to "play" a flight recorded > > > by an external > > > source is different from the ability to save/load a > > > flight from FG. > > > In other words, I don't think we should save any > > > state variable - ie > > > parts of totality of the property tree. > > > We have an initial state when FG is launched with a > > > specific set of > > > parameters. Now how do you fly ? You use your > > > joystick, mouse, > > > keyboard et al to interact with the simulator. So a > > > recorded fligth > > > could be defined as a list of user interactions > > > paired with a time stamp, > > > and to be more accurate a very limited set of > > > properties could be added > > > lets say every 10 or 20 seconds (position, heading, > > > etc). > > > The advantage would be : > > > - short record file size > > > - accurate property tree because the simultor > > > would run exactly with > > > the same imputs > > > - easy to implement because it is not tied to > > > the internals of the > > > simulator (like fdm). > > > > > > Harald. > > > > > > > > > _______________________________________________ > > > Flightgear-devel mailing list > > > [EMAIL PROTECTED] > > > > > http://mail.flightgear.org/mailman/listinfo/flightgear-devel > > > 2f585eeea02e2c79d7b1d8c4963bae2d > > > > > > > > > > > ___________________________________ > > Yahoo! Mail: gratis 100 MB per i messaggi e allegati da 10 MB > > http://mail.yahoo.it > > > > _______________________________________________ > > Flightgear-devel mailing list > > [EMAIL PROTECTED] > > http://mail.flightgear.org/mailman/listinfo/flightgear-devel > > 2f585eeea02e2c79d7b1d8c4963bae2d > > > > > _______________________________________________ > Flightgear-devel mailing list > [EMAIL PROTECTED] > http://mail.flightgear.org/mailman/listinfo/flightgear-devel > 2f585eeea02e2c79d7b1d8c4963bae2d _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d
