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.
- 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.
Fix the leg distance calculation to display nautical miles instead of meters.
It turns out that Simgear already has a range normalize function, so I use
that one instead.
I've added a vertical navigation capability to the GPS module. One can input
two waypoints, wp[0] and wp[1], with altitude. If the altitudes differ, then
the altitude deviation from a "straigth" line from wp[0] to wp[1] is
calculated. The true course and course deviation from wp[0] to wp[1] is also
calculated. All this can be found in the wp subdir where one also finds the
wp[0] and wp[1] subdirs.
All this has to be done through the property browser. Maybe I should make a
gui window for the GPS!
I've added a tracking bug to the gps. This is of course very similar to a
heading bug for a DG. I don't know if this is the common name, but I feel
that for a gps the name tracking bug is more accurate than heading bug. A
true bug error and a magnetic bug error is calculated and shifted into the
-180 to 180 range so that they can be used by autopilots.
I've also fixed a property name that crept in when I had to change back to
indicated-***. Back then I accidentally changed the desired course name to
"indicated-course". The property that is supposed to be the input for the
desired course should naturally be named something like "desired-course", and
definitely _not_ "indicated-course". If this name change breaks anything it
should be fixed in the other end.
I've also commented out a lot of #includes that I don't think is needed. I'm
on Suse 9.0 now, and it builds fine here, but this might be a problem for
different platforms I guess we have to cross our fingers.
I've done som more work on the gps instrument.
- You can now input airport-, nav- or fix-ID to select a waypoint.
- You have to specify either "airport", "nav" or "fix" in the waypoint-type
property (some fixes and navs have identical IDs).
- Formatted the time to waypoint output.
- Cleaned up and changed some propery names (wp-heading -> wp-bearing).
- I've also added a name member to the FGNav class so that the gps instrument
can get the name of the nav.
- Changed the airport name parsing in simple.cxx.
explicitely. This value has always been feet, but there were a couple places
in the code that assumed this elevation was meters. The result was that you
could park directly over the top of the Black Forest VOR (112.50) NE of KCOS
and get a dme reading of 2.5 or so. This problem is now resolved.
places now use sgCartToGeod() instead of rolling their own
approximation. And YASim is now using exactly the same 3D coordinate
system as the rest of FlightGear is.
These patches add a clock instrument, which allows to model failure ("serviceable") and to adjust the time independently of the system time (defaults to GMT). The main incentive is to make the p51d clock work and adjustable via the knob.
o Offers a time string ("12:03:15") for the LCD or for LED
clocks, or an empty string in case of failure/power off. The
instrument assumes that digital clocks are battery buffered,
so they will be updated even if there's nothing on the display.
o Offers the number of seconds since midnight for analog
clocks, like in the p51d. This number is not increased
if !serviceable. So the clock will stand still and continue
where it stopped when it's serviceable again.
I did not consider voltage yet, because the Mustang's clock will need a lot more current than the LCD clock. The instrument is updated 4 times per second but returns immediately if neither time nor offset changed. The function getGMTString() in fg_props.cxx could be removed after applying these patches.
scene management code and organizing it within simgear. My strategy is
to identify the code I want to move, and break it's direct flightgear
dependencies. Then it will be free to move over into the simgear package.
- Moved some property specific code into simgear/props/
- Split out the condition code from fgfs/src/Main/fg_props and put it
in it's own source file in simgear/props/
- Created a scene subdirectory for scenery, model, and material property
related code.
- Moved location.[ch]xx into simgear/scene/model/
- The location and condition code had dependencies on flightgear's global
state (all the globals-> stuff, the flightgear property tree, etc.) SimGear
code can't depend on it so that data has to be passed as parameters to the
functions/methods/constructors.
- This need to pass data as function parameters had a dramatic cascading
effect throughout the FlightGear code.
appears still to be indicating.
Added a 'caged' property to the AI, for aerobatic work.
Temporarily disabled tumbling due to pitch, until I can learn more
about it.
Publish the current amount of tumble (-1.0:1.0) under
/instrumentation/attitude-indicator/tumble-norm.
proceed to search for an VOR of that same frequency. On rare occasion
this search could return true with a far distant VOR and cause a small
amount of confusion.
for a little while, since it uses different properties. There are
some improvements, especially with searching and range. It also has
its own serviceable and in-range properties, independent of any
coupled VOR.
a spinning gyro.
Changed FGInstrumentMgr to inherit from FGSubsystemGroup, greatly
simplifying the (already simple) class. I should probably rename this
to FGInstrumentGroup or something similar, but not today.
Added the gyroscopic turn indicator (part of the TC).
Ok, I found the problem. You're computing the dynamic pressure in
"psf" and adding it to the static pressure in "inHg" to form the
total pressure. The attached patch is the simple fix to the source.
With that fix, failing the pitot while in cruise at 3k' will cause
the airspeed to indicate beyond redline during climb ... well before 4k'.
Thus, a pitot problem can be detected on any IFR altitude change.
Similarly, failing the static (with working pitot) while cruising 4k'
causes the airspeed to indicate beyond redline during a descent
well before reaching 3k' (during which, of course, the ALT looks fine).
Thus, a static failure can be detected before the aircraft breaks out
of the pilot tolerance range and is blatantly conspicuous soon after.
