Upon further review, I was very misguided, and unfortunately no one slapped
my hand at the time.
Factoring in the environment manager's interpolation scheme, it makes complete
sense to specify the sea level temperature at each boundary and aloft layer.
In fact, this is the only way that allows the temperature interpolation to
make sense, especially around the boundary layer. This is confusing stuff,
but it now works perfectly. :-)
Square the normalized direction acceleration for the y and z axes, so
that turbulence predominantly affects pitch.
Bind to the /environment/turbulence/magnitude-norm and
/environment/turbulence/rate-hz properties in FlightGear.
between temperature at altitude vs. temperature at sea level. The dialog
box asked for temperature at altitude which makes sense, but all the
internal crunching expected temperature at sea level. However, it makes no
logical sense to specify the sea level temperature for different layers so
I changed the internal processing to work with temperature at altitude and
then derive an approximate sea level temperature at the end.
If you know the ground temperature, you can just enter this temperature
for the first boundary layer and the system should do the right thing.
etc.
Improved the weather system to interpolate between different
elevations and deal with boundary-layer conditions. The configuration
properties are now different (see $FG_ROOT/preferences.xml).
- Removed some old cruft.
- Removed some support for older versions of automake which technically was
correct, but caused the newer automakes to squawk warnings during an
initial sanity check (which isn't done very intelligently.)
NOTE: this fix is technically not correct for older version of automake.
These older version use the variable "INCLUDES" internally and could have
them already set to an important value. That is why we were appending
our values to them. However, newer versions of automake don't set this
value themselves so it is an error to append to a non-existant variable.
We seem to "get away" with overwriting the value on older versions of
automake, but if you have problems, consider upgrading to at least
automake-1.5.
1. Typo where /environment/density-inhg instead of
/environment/density-slugft3 was flagged as archivable.
2. Density should no longer be archivable anyway, since it is
calculated internally and not directly settable by the user.
temperature, and dewpoint. The /environment/density-sea-level-slugft3
property has been removed, and the /environment/density-slugft3
property is read-only.
layers. The properties controlling each layer are inside
/environment/clouds/layer[n], and the available properties are type
("clear", "overcast", "mostly-cloudy", "mostly-sunny", or "cirrus"),
span-m (should be about 40000), elevation-ft, thickness-ft, and
transition-ft.
Stratosphere). The atmospheric properties are as follow:
/environment/temperature-sea-level-degc
/environment/temperature-degc
/environment/pressure-sea-level-inhg
/environment/pressure-inhg
/environment/density-sea-level-slugft3
/environment/density-slugft3
Setting either the sea-level or altitude value automatically sets the
other value appropriate, except for temperature at altitude above the
Troposphere (where there's no reliable way to back-calculate it). The
atmosphere model appears in the atmosphere_data array in
environment.cxx, and can easily be extended into the upper
stratosphere and beyond.
These are not yet tied into the FDMs or steam module.
object rather than a pointer.
FGEnvironment now has the beginning of an atmospheric model, and will
recalculate temperature (not pressure or density, yet) based on
elevation.
FGEnvironment has a copy constructor.
- changed FGSubsystem::update(int) to
FGSubsystem::update(delta_time_sec); the argument is now delta time
in seconds rather than milliseconds
- added FGSubsystem::suspend(), FGSubsystem::suspend(bool),
FGSubsystem::resume(), and FGSubsystem::is_suspended(), all with
default implementations; is_suspended takes account of the master
freeze as well as the subsystem's individual suspended state
- the FDMs now use the delta time argument the same as the rest of
FlightGear; formerly, main.cxx made a special case and passed a
multiloop argument
- FDMs now calculate multiloop internally instead of relying on
main.cxx
There are probably some problems -- I've done basic testing with the
major FDMs and subsystems, but we'll probably need a few weeks to
sniff out bugs.
default implementation that uses user-supplied params. Currently, the
only parameters are
/environment/params/base-wind-speed-kt
/environment/params/gust-wind-speed-kt
but others will show up soon (i.e. sheer, variable direction, variable
visibility, etc.). To activate these properties, you have to
configure --with-new-environment.
The gusting function is simplistic and needs to be replaced with
something better, though it doesn't feel too far off.
Added two new properties:
/environment/temperature-sea-level-degc
/environment/pressure-sea-level-inhg
These are now supported in FGEnvironment as well, though they always
have the same value for now. They need to be hooked up to the FDMs.
different locations, and hitched it into FGGlobals. FGEnvironmentMgr
has taken over as the subsystem, while FGEnvironment is simple the
information that it returns. I've removed current_environment
completely -- everything now uses properties or goes through
FGGlobals. FGGlobals itself has a couple of useful methods:
const FGEnvironment * get_environment ();
const FGEnvironment * get_environment (double lat, double lon, double alt);
The first one returns the environment data for the plane's current
position, while the second returns the environment data for any
arbitrary location. Currently, they both return the same information,
but that will change soon.
