JSBSim (def), YASim and 'magic' - zlib > Note: JSBSim config files allow the user to specify a log file to be generated
Wow! Yes, when I looked around after the 'flight' I saw this abt 6 MB csv file, and wondered - 'where did that come from?'. I had a quick peek inside and deleted that first one ... But I have now done another partial flight using the 'default' c172.xml and there is some interesting information in (this time 4 MB) csv file ... You can 'see' that it took some 2 minutes - 130.792 secs to be exact - before i got the engine rolling ... so that's some 1310 lines (@ 10 HZ) of csv that yield little ... One can be puzzled why the last column, very largely labeled engine[?].RPM starts at 1071.807 RPM, but over the next 10-15 secs falls to a low of 759.0082 - yes, engines seldom hold a 'constant' rpm, but ... abt row 1730 (173 secs) i apply throttle, and the RPM quite quickly climbs to 2100 at row 1800 (abt 180s)... It is not until row 1781 that i can see the 'Altitude' move above abt 4.66 (column 'AU' - 177.892 seconds) of the SF runway ... Lift (column 'AA') has risen to -25 somethings ... so i got LIFT ... By row 2350 - 235 secs - i am passing thru 500 feets - rising gently ... RPM holding around 2100+ ... At row 2486 (248 secs) i hit 'p' to pause, and could never get things going again ... Even had to use Ctrl+C on the CONSOLE screen to exit the sim ... Yes, yes, yes - very facinating stuff. Full of useful information on the 'plight' of the FDM - keeping prefect double precision track of so many variables - engine and airframe ... this is good. But IMHO i hope this can soon become OFF, or should i say "NONE", in the 'default' release 0.7.9 c172.xml? A newbe trier of fgfs should 'see' the thing operate at its best ... Have so 'adjusted' my c172.xml, and that last JSBSim try left no 'trace' ... And to again say g'by to QNAN forever ... --fdm=yasim Meantime have also flown again with YASim, and c172-yasim ... This time as the first thing after machine boot, and it flew as-well-as-can-be-expected. --fdm=magic To be able to 'see' how the sim handles travel across the earth, there is nothing to beat 'magic' ... Those of you 'lumbered' with WIN32 *must* try this ... Watch those tiles tumble forward ... And as I have often repeated, it seems to me the main fgfs problem in WIN32 - using my msvc6 compiled debug exe - is all to do with memory of course, and disk io ... And i am sure some of that is due to using the windows memory mapping of files (in metakit at least). A simple check to see if the sim is humming yet, or i should wait some more, is to click the Brake ON, and if the panel lights up almost immediately ... And sound(s) becomes continuous ... But with JSB and YA sims, they 'see' a wheel brake, and even if there is an imperceptable forward aircraft motion, the FDM compresses the front wheel springs, and pitches the ac forward ... This means the outside scene must be completely redone for each small change in the ac pitch ... and it becomes a racey disk io bottle neck. DirectX wants to repaint full scene, and during that delay the FDM had actually rocked another degree or 2 forward, which changed the scene again ... But as stated, at certain times, sometimes for many seconds - maybe you've sat cluching the js for dear life trying not to move it for 1/2 minute before, but - :-)) the simulator FLIES :-)) It flies. Ordinary co-ordinated eye-hand movement can control / postion the ac exactly where you would like it to be ... fdm 'magic' is far less 'jittery', thus the system's memory managment, including cached io, mapped io, ..., etc catch up more frequently, and then i can see 30 fps plus. Assuming i have taken on 15000 feet in altitude, and swung around to 090 I can give it FULL throttle ... Unfortunately magic's max. speed is clamped to only 3600 kts. i love FS2000's 32767 kts in slew mode and must find a way to speed-up magic ... *** zlib *** One day it's there - the next day it's not. Sad that we lost poor little zlib ... :-(( rgds, Geoff. ps: Tks., Curt for the system.fgfsrc --fg-scenery=D:\FG... tip. It works fine, naturally :-) _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
