this is to use some kind of utc time for timestamps in mp protocol,
to improve the lag correction system for mp planes, using a
"real time" mode when possible.
Only apply the fix for time-zone offsetting on Windows, since Unix
is handling mktime differently. (Arguably we should also apply a
conversion for Unix systems, but the previous logic worked)
It's common to use SGTime to calculate the the Julian Date, without providing time-zone information. Don't warn in these cases, since the behaviour is fine.
Adapt the freealut code into a WAV-file reader. As a side-effect, it would now be possible to deploy WAV files compressed with gzip, since we use ZLib's gzread functions to read from disk.
Implement sleeping to an absolute timestamp
as well as sleeping for a relative time in
SGtimeStamp.
The reason for including this into SGTimeStamp
is that the timestamps internals are required to
do accurate sleeps to and absolute timestamp
for the posix timer implementation.
Have a more general timestamp implementation.
Very useful for higher accuracy timings.
Modified Files:
simgear/structure/subsystem_mgr.cxx
simgear/structure/subsystem_mgr.hxx
simgear/timing/testtimestamp.cxx simgear/timing/timestamp.cxx
simgear/timing/timestamp.hxx
pun intended) that I'm touching the time library.
Brian Schack reported that the traffic scheduler messes up the timestamps
of the atlas network output. As it turns out, the c library functions
asctime, and gmtime use a static copy of the tm struct to do the internal
formatting. Our linux port of the SGTime class, incidentally, also stored
it's master time stamp in this very same struct. Thus, formatting an
arbitrary time value, would have the unwanted side effect of time travel.
Usually, this would go unnoticed, because the actual time parameters would
be updated before any damage could be done. But unwanted side effects, as
in Brian's example could occur.
On the MSVC port this appears to not have been a problem. Since that port
used a copy of the tm struct to store it's master time stamps. Since the
MSVC code also compiles cleanly on linux, it seems to be the way to go to
use that approach. In addition, it also removes some conditional compile
directives.
I've only run a short test, but didn't see any undesirable side effects.
the MSVC and MipsPro warning stuff).
As a result of this patch, simgear/sg_traits.h can be deleted. So can SGCMath.h,
but I'll do that separately.
There is one more 'mechanical' change to come - getting rid of SG_USING_STD(X),
but I want to keep that separate from everything else. (There's another mechnica
l change, replacing <math.h> with <cmath> and so on *everywhere*, but one step a
t a time)
that interdependencies between sg libs are generally unwelcome, but
sg_exception is a rather basic part, and it's already used by xml, props,
scene, sound and, of course, structure. Since props and xml are core
libs, we can assume that sg_exceptions are available. (OK'ed by Curt)
James Turner