will delay it's reply by 50ms. The ground station can change it's reply delay
to trick the airborn dme unit into reporting a distance that is offset from
the true distance by some constant value. In FG we model this by subtracting
a fixed distance from the actual distance.
It is thus possible in our implimentation for the displayed distance to become
negative. This patch clamp DME distance to a minimum value of 0.00 so it can
never go negative.
A good elevation is critical for proper glide slope modeling. This patch
assigns the average field elevation to any ILS component that doesn't have
a valid elevation.
Also, for an ILS approach, use the GS transmitter elevation for glide slope
calculations rather than the localizer elevation, in some cases this can
make a big difference.
- FG now directly supports Robin's native nav database file format.
- His latest data now separates out dme, gs, loc, and marker beacon
transmitters rather than lumping them all into a single "ILS" record.
- These new data structure changes prompted me to do some code restructuring
so that internally these different types of navaids are all kept as
separate lists and searched and handled separately.
- This structural change had a cascading affect on any code that
references or uses the nav databases. I've gone and "touched" a lot of
nav related code in a lot of places.
- As an added bonus, the new data (and code) adds DME bias so these will
all now read as they do in real life.
- Added Navaids/navdb.cxx and Navaids/navdb.hxx which provide a front
end loaders for the nav data.
- Added Navaids/navrecord.hxx which is a new "generic" nav data record.
- Removed Navaids/ils.hxx, Navaids/ilslist.cxx, Navaids/ilslist.hxx,
Navaids/mkrbeacons.cxx, and Navaids/mkrbeacons.hxx which are all now
depricated.
Add FGPredictor class to xmlauto. Add support for horizontal navigation based
on flight track as opposed to heading. Add crosstrack-error support to nav.
Simplify error adjust calculation for horizontal nav (better interception).
Fixed potential divide by zero that was producing nan issues in the xmlauto
code.
immediate end to glut, only that I'm going through and cleaning up (and
taking inventory of the actual glut dependencies in case I want to investigate
SDL.)
clarity:
nav_radial => nav_target_radial (same as selected, except for a LOC)
nav_heading => nav_reciprocal_radial
nav_magvar => nav_twist (it's not always the same as magvar)
nav_heading_needle_deflection => nav_cdi_deflection
nav_gs_needle_deflection => nav_gs_deflection
Added nav_radial back in, but now it shows the current radial from the
VOR, as one would expect. This value also appears in the
/radios/nav[*]/radials/actual-deg property.
This patch exposes the nav_id--Navaid (VOR/ILS) IDs--in the property tree for use in EFIS displays. Both the string and individual integer (char) values are published.
Erik Hofman:
I have converted all sprintf() functions in navcom.cxx into snprintf() for some extra securety.
