On Friday 02 May 2008 08:50, Melchior FRANZ wrote: > * Syd -- Friday 02 May 2008: > > I see some commited from Melchior that suggest he might be > > working on a solution, just not sure what that is yet :) > > Sorry, no. I'm not working on anything like that. Just fixed the > missing-unit-suffix bug. (Though the distance should really be > in meters internally, not nm.) > > I don't agree with Lee's suggestion to use the tail as reference > point in all FDMs. That's abusing the FDMs internal reference > system. Unfortunately, we don't have any information about the > location of the gear or other dimensions in the property tree. > What comes closest is <chase-distance-m>, which is why this is > abused for guessing the aircraft size in fly-by-view. But it's > often set badly, especially in bigger aircraft. (We could > probably ask the scenegraph for the bounding box, but that > wouldn't help much for positioning on the runway.) > > The simplest solution would be to allow defining an offset that's > by default 0, and let fgfs add that to the reference point for > positioning. > > m.
I'm not very bothered about this issue so I don't care much about which solution is used but I am curious about why using the tail location as the visual reference point is abusing the FDM's internal reference system but using the nose is not. I'm not aware of any intrinsic functional difference between the two. Isn't the chase distance, along with the view angle, a user preference setting? If so, how can we justify saying that a user preference is set badly? Although we set default values for both chase distance and view angle to give a view that is usable, we should assume that users will change both of these using the menu options specifically designed for that purpose. Estimating the size of an aircraft upon either of these user preference settings isn't going to be reliable. On the other hand though, the primary purpose of the chase distance is to set the viewing distance in external views, so it would be appropriate to use it in the fly-by view:) I'm not looking for any arguments here - just the reasoning. I only suggested that the tail be used as vrp because it would ensure that the landing gear is on the runway but perhaps for helis it might be better to use the rotor axis for single rotor craft, or the front (or rear) rotor for multi-rotor helis. LeeE ------------------------------------------------------------------------- This SF.net email is sponsored by the 2008 JavaOne(SM) Conference Don't miss this year's exciting event. There's still time to save $100. Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone _______________________________________________ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
