While troubleshooting the new environment I discovered the metar station
elevation (station_elevation_ft) is never being set because there is a
local variable that overrides it.
is fired. Immediately fetch and wait for the METAR before continuing. This gets the
/environment/metar/xxx properties filled before nasal-dir is initialized.
The quotes form is normally only used for headers with path relative
to the including file's path, though the standard doesn't strictly
mandate this. This is consistent with the rest of sg/fg, it makes the
code's intent clearer and helps to find headers. (And it's a few
milliseconds faster, too.)
static FGAirport helpers. As a result, another global index goes away. Use
the helpers to avoid ugly FGPositioned down-casts in various places.
Also converts the environment/METAR code to deal with FGAirport pointers,
instead of string identifiers, and contains work-in-progress code to implement
the AirportList dialog using FGPositioned. This isn't enabled yet for various
reasons, but is the final piece to allow FGAirportList to be removed.
gone. This is good news, since the old query was implemented as a linear
search, sorted by Manhattan distance, and with a warning not to use the logic
at runtime. Various systems (such as the Mk-VIII) do query such data often,
eg every second.
Also gets Point3D out of Airports/simple.hxx, as a precursor to removing it
completely.
reverts one of my changes which ensured that the 3D clouds were updated with
METAR. Unfortunately this had the side-effect of over-writing the environment
properties, and therefore nuking the interpolation work.
Attached is yet another 3D clouds patch, to fix the following:
1) The 3D clouds were not modified by the cloud coverage, due to some problems with osg::Switch
2) METAR changes to cloud coverage were not obeyed.
3) Making changes via the Cloud dialog had no effect unless 3D clouds were toggled.
4) Cloud cover was too sparse.
5) 3D Stratus clouds caused performance issues on some hardware (fixed by removing 3D stratus from cloudlayers.xml - it will now be a 2D layer).
- Replaces simple shader attributes with vectors (this was missed out of the last patch by mistake)
- Includes Yon's Fog update code (Thanks!)
- Fixes a bug since 1.0 where --enable-real-weather-fetch stopped the other weather scenarios from working.
- this exposed a bizarre issue on Mac where dragging in <AGL/agl.h> in
extensions.hxx was pulling in all of Carbon to the global namespace
- very scary. As a result, I now need to explicitly include CoreFoundation
in fg_init.cxx.
- change SG_USING_STD(x) to using std::x
the next airport or airport with METAR station, but about any type of
airport
- as a side effect this change makes it also 30 to 50% faster :-)
In the long run this linear search shall be replaced with a spatial
algorithm (like octree), which will be a much bigger performance gain.
Anders said:
With Stuart's help I've looked closer at this and I think I've tracked
down the cause of the problem:
At least on my computer the sort() call on line 234 in
Environment/environment_ctrl.cxx sorts the vector entries by memory
address instead of altitude, i.e. the custom comparison predicate is not
used. This causes the tables of environment conditions to be reordered
into a wrong order at some weather updates, depending, basically,
on where the memory allocator places the objects. (Btw. why are they are
freshly allocated for each update?)
"interpolates METAR changes over time as follows:
1) Wind changes are interpolated as vectors, so the change is much more
natural than before - no-longer will your aircraft be suddenly shoved to
one side.
2) Visibility is interpolated as an X-value, which looks pretty neat.
3) Cloud heights and thicknesses are interpolated if they are close to the
aircraft. Cloud textures are not."
mf:
pthread_cancel doesn't seem to work correctly on all supported platforms.
It apparently causes SGBlockingQueue::pop() to correctly leave the thread on
the cancellation point pthread_wait(), but the SGGuard() destructor isn't
called, so the queue mutex remains locked. This triggered an assert() on
pthread_join(). This patch uses an empty ICAO request as signal for the
thread to terminate itself.
- remove cleanup handler that unlocks unused mutex
- make the result_queue a locking queue (blocking is only done in the
pop() anyway, and this isn't used in the thread at all)
- don't disallow thread cancelling in the request_queue's pop(), which
is the only cancellation point in this thread
metar fetcher. Effectively this caused the metar thread and the main
thread to both attempt to fetch weather data. This could lead to long pauses
when the main thread decided to fetch the weather, and introduced a race
condition that could cause a segfault/crash.
Investigating this issue, I discovered that even longer ago, someone confused
#defines and #ifdef symbols with C/C++ variables. If I #define XYZ 0 it is
defined so #ifdef XYZ is true, not false like a variable. Our thread
detection made this mistake and there were follow up patches to work around
it.
So I fixed the configure script (ahhh, reading the autoconf manual is highly
recommended excercise for people editing the configure.ac file.) I also
discovered that we were hardwiring with_threads=yes with no way via configure
options to disable threads from the build so I fixed that.
Then I patched up the #ifdef's scattered through the code to match the
configure script changes, oh and by the way, I stumbled upon a past typo
that led to the race condition in the metar fetching thread and fixed that.
too old (wrong system time or broken proxy): stops after 10 stale reports
were fetched in a row. This should simply stop further fetching, but due
to a bug in the threading system(?) it does currently lead to abortion,
just like any other exception in the fetcher.
I tried to make sure accessor functions which return by reference act
on const objects. also replaced some iterators with const_iterator
and a few return/pass by reference that were missed the first time
around.
* Use "const string&" rather than "string" in function calls when appropriate.
* Use "const Point3D&" instead of "Pint3D" in function calls when appropriate.
* Improved course calculation in calc_gc_course_dist()
* Safer thread handling code.
Vassilii Khachaturov:
Dont use "const Point3D&" for return types unless you're absolutely sure.
Erik Hofman:
* Use SGD_(2)PI(_[24]) as defined in simgear/constants.h rather than
calculating it by hand every time.
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.
