Attached is a patch to the airport data storage that I would like committed
after review if acceptable. Currently the storage of airports mapped by ID
is by locally created objects - about 12 Meg or so created on the stack if
I am not mistaken. I've changed this to creating the airports on the heap,
and storing pointers to them - see FGAirportList.add(...) in
src/Airports/simple.cxx. I believe that this is probably better practice,
and it's certainly cured some strange problems I was seeing when accessing
the airport data with some gps unit code. Changes resulting from this have
cascaded through a few files which access the data - 11 files are modified
in all. Melchior and Durk - you might want to test this and shout if there
are problems since the metar and traffic code are probably the biggest
users of the airport data. I've also added a fuzzy search function that
returns the next matching airport code in ASCII sequence in order to
support gps units that have autocompletion of partially entered codes.
More generally, the simple airport class seems to have grown a lot with the
fairly recent addition of the parking, runway preference and schedule time
code. It is no longer just an encapsulation of the global airport data
file, and has grown to 552 bytes in size when unpopulated (about 1/2 a K!).
My personal opinion is that we should look to just store the basic data in
apt.dat for all global airports in a simple airport class, plus globally
needed data (metar available?), and then have the traffic, AI and ATC
subsystems create more advanced airports for themselves as needed in the
area of interest. Once a significant number of airports worldwide have
ground networks and parking defined, it will be impractical and unnecessary
to store them all in memory. That's just a thought for the future though.
- replay.cxx :
corrected a bug, now reinitialize the recording data when replay is
deactivated
- fgclouds.cxx :
cloud layers and weather condition are saved when choosing a weather scenario,
added a new scenario 'none' so we can switch back to standard flightgear
weather
- navradio.cxx :
force a search() on init to initialize some variables, preventing a nearly
infinite loop when delta-time == 0 on the first update()
- electrical.cxx :
uninitialized variable in apply_load() for FG_EXTERNAL supplier
- panel.cxx, panelnode.cxx :
added a property "depth-test" for 2.5D panels so that they update the depth
buffer and are no more visible from the outside of the aircraft when the
aircraft uses textures without an alpha channel
- panel.cxx :
moved the computation of the instruments diffuse color outside the
texturelayer code since this is constant during a frame, this is a big speedup
for 2D panels
I did some profiling of the code and found a few interessant things. Some corrections are obvious like the one in the multiplayer code, the fps is no more divided by 2 or 3 when another plane is on screen.
Other things like collision detection and computation of agl can not really be optimized. I changed a few things in hitlist.cxx but this only give a very low increase of fps. The groundcache eats a lot of cpu but I think that the real way to do it is to use a real collision system like OPCODE or something like that.
And I added an option to disable the recording of replay data. It takes more cpu than we can think.
Changes
=======
- panel.cxx :
moved the computation of the instruments diffuse color outside the texturelayer code
since this is constant during a frame, this is a big speedup for 2D panels ;
- hitlist.cxx :
changed the computation of the intersection between ray and triangle, optimized
the sphere culling by using a normalized direction vector. This can give a
35% speedup on the computation of elevation in some situations ;
- renderer.cxx, acmodel.cxx :
call ssgDrawAndCull with plane scene graph in external or internal view,
calling ssgDrawAndCull with the root scene graph was drawing other players plane
a second time in multiplayer mode ;
- mplayer.cxx :
removed the calls to ssgFlatten and ssgStripify because it was degenerating models,
causing a massive drop in frame rate ;
- replay.cxx :
added an option to disable the recording of the flight
- fgclouds.cxx :
changed the path of cloudlayer properties to match preferences.xml ;
set the altitude of clouds from scenarios to a more correct value if metar is not enabled ;
Changes
=======
- correct the transparency probleme when old 3d clouds were enabled
(rendering context with an alpha channel)
- changed rain cone orientation, it can now be viewed from helicopter or chase
view (still not tower view)
- clouds are a bit more yellow/red at dawn/dusk
- weather data is now correctly propagated to the interpolator, this correct
visibility, wind, etc
- the 'metar' weather scenario now immedialty reuse the real metar data
- real metar no more overwrite custom weather scenario
This is another update for the cloud code, a lot of lines but this time I have started to add the doxygen doc.
Misc
====
- corrected a bug when RTT is not available, the current rendering context was
altered
- if RTT is not available then 3d clouds are not drawn at all
- impostors lighting is now recomputed when the sun changes position
- distant objects are no more seen in front of clouds
- blending of distant clouds is a bit better now
- litle optimization of code (uses a less cpu time)
- use layer wind speed and direction (no more hardcoded wind)
- fov is no more hardcoded
Changes
=======
- clouds (cu only) are dissipating/reforming (experimental)
- compute a turbulence factor that depends on surrounding clouds and type of
clouds (experimental)
- clouds shapes are defined in cloudlayers.xml
- type of clouds present in a layer is also defined in cloudlayers.xml
- cloud layers are generated from metar and other misc. data (in progress)
- added a rain effect around the viewer (enabled in the rendering dialog and
when the metar property says so)
- added a lightning effect (enabled in the rendering dialog) : cb clouds spawn
new lightnings
- added a dialog to select from different weather source : metar/property,
a 'fair weather' environment and a 'thunderstorm' environment.
Changes
=======
- corrected some strange behavior when playing with the render dialog options
- the density slider is now working : if you are fps limited and still want to see clouds in
the distance you should play with that
- added the choice for texture resolution, its more comprehensible now (before it was
wrongly allways choosing 64x64 textures)
- changed the initial texture size : you now have 64 texture of 64x64, this uses 1Mo of
texture memory (before it was 20 texture of 256x256, that took more memory and there was
not enought impostors)
- sun vector is now right so the lighting is a bit better
- removed useless sort and light computations for impostors, this should save a lot of cpu
- blending of distant cloud is more accurate now
- clouds are now positioned correctly, they don't try to escape you anymore
- no more red/white boxes around cloud
- textures are now filtered (no more big pixels)
known bugs
==========
- distant objects are seen in front of clouds
- new and updated sources for the new volumetric clouds
- 2 new textures for the clouds
- an update to the render dialog to enable/disable and change a few parameters
for the new clouds
ssgSetNearFar(). This by default creates a symmetric view frustum which is
typically what an application wants.
However, to get control of the view frustum in order to build support for
asymmetric view frustums, we need to wrap these calls with a bit of our own
logic.
This set of changes wraps all calls to ssgSetFOV() and ssgSetNearFar() with
FGRenderer methods.
I also standardized how the FGRenderer class is handled in globals.[ch]xx.
This led to some cascading changes in a variety of source files.
As I was working my way through the changes, I fixed a few warnings along
the way.
I just heard from John Wojnaroski that you and he are going to work on getting
a flightgear demo machine up for the linux expo thursday and Friday. John
indicated that he would very much like to get a CVS version with the new
traffic code up and running before the expo.
The following patches to SimGear & FlightGear ...
- create an FGMetar abstraction layer, whose purpose is:
* provide defaults for unset values
* interpolate/randomize data (GREATER_THAN)
* derive additional values (time, age, snow cover)
* consider minimum identifier (CAVOK, mil. color codes)
- add rain/hail/snow/snowcover support on the METAR side
- add max age of METAR data handling (currently set to
- add support for an external METAR cache proxy server
- add CAVOK handling
- set missing year/month in regular METAR messages
- fix a small bug in metar.cxx (wrong return value)
a single apt.dat.gz file which is in the native X-Plane format.
To do this I wrote a front end loader than builds the airport and runway
list. Some of the changes I needed to make had a cascading effect, so there
are minor naming changes scattered throughout the code.
configure and compile out-of-the-box on a MinGW target:
Use -lSDL instead of -lglut32 on windows builds when --enable-sdl
is set.
Link against alut.dll in addition to openal32.dll.
Replace BSD bcopy() with ANSI C memmove() in a few places. This is
simpler than trying to abstract it out as a platform dependency in a
header file; bcopy() has never been standard.
The ENABLE_THREADS handling has changed to be set to 0 when threads
are not in use. This breaks expressions like #ifdef ENABLE_THREADS.
Replace with a slightly more complicated expression. It might have
been better to fix the configure.ac script, but I didn't know how and
this whole setting is likely to go away soon anyway.
The MinGW C runtime actually does include snprintf, so only MSVC
builds (and not all WIN32 ones) need _snprintf in JSBSim/FGState.cpp
Building on a platform with no glut at all exposed some spots where
plib/pu.h was being included without a toolkit setting (it defaults to
glut). Include fg_os.hxx first.
And when still using glut, glut.h has a bizarre dependency on a
_WCHAR_T_DEFINED symbol. It it's not defined, it tries to redefine
(!!) wchar_t to disasterous effect.
occasionally cause a large number of valid stations to be flagged as invalid.
This *seemed* like a "race condition" type problem because there were some
assumptions in the communication between the main process and the threaded
loader which if they broke down could lead to this problem.
In the process of removing this ambiguity, I restructured the threaded
(and non-threaded) metar fetching code a bit. Some of the top level logic
(which Erik politely left untouched) didn't make nearly as much sense in the
context of a threaded metar loader and could have contributed to some of the
wierdness I was seeing.
updates based on the "closest" airport with metar data available. Note that
the web based query is in the main loop and causes brief sim pauses. Update
rate (once per minute) needs to be tweaked with, but is a good value for
testing.
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.
