Curtis L. Olson writes: > > Stewart Andreason wrote: > > > Jim Wilson wrote: > > > >> There are a couple bugs or at least they were there a week or so > >> ago. One is > >> just a mapping typo where latitude goes into both latitude and > >> altitude. The > >> other is under linux the fg-root and fg-scenery parameters don't get > >> saved and > >> passed on to fgfs (no prefs.set done) unless you hit previous to display > >> page[0] (the function that processes page[0] saves those strings). > > > > > > Ah, is this why fgfs get stuck in a freezing loop, when I give > > latitude and longitude parameters at the command line? > > > > (Tries a few more runs) > > Ah! that's it. If I give a --lat that is less than the ground > > elevation, it freezes in a loop. and ignores the --altitude parameter. > > > > I believe I reported this Jan.11, but had not figured out the exact > > conditions that triggered it. > > Thanks Jim. > > > > A serious bug. > > > I can explain the bug to you. If you specify a lon/lat that lies on the > *exact* border between two tiles (i.e. --lat=90 --lon=45) then at > startup the ground intersection code can fail. This means that the > scenery subsystem never returns a valid groud elevation. Now the > problem is that the flight dynamics model *needs* to know the ground > elevation before it can position the aircraft. Complicating the matter > is that when the FDM is first initialized the tiled scenery loader may > not have the current tile loaded yet. So the FDM doesn't know if it's > in a dead lock state or if it just needs to wait a bit longer for the > threaded tile loader to catch up. > > The solution would be to make the ground intersection code more robust > to this boundary condition, but I believe that might be burried deep in > plib.
This might help hitlist.cxx inline static bool IN_RANGE( sgdVec3 v, double radius ) { - return ( sgdScalarProductVec3(v, v) < (radius*radius) ); + return ( sgdScalarProductVec3(v, v) <= ((radius*radius) +FLT_EPSILON) ); } but I don't see where setting the lat less then the ground elevation has any bearing on this < this sounds more like a parsing error > Norman _______________________________________________ Flightgear-devel mailing list Flightgear-devel@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d