#include "TimeManager.hxx"
-#ifdef _WIN32
-# define WIN32_LEAN_AND_MEAN
-# include <windows.h> // for Sleep()
-#else
-# include <unistd.h> // for usleep()
-#endif
-
#include <simgear/timing/sg_time.hxx>
#include <simgear/structure/event_mgr.hxx>
#include <simgear/misc/sg_path.hxx>
TimeManager::TimeManager() :
_inited(false),
- _impl(NULL)
+ _impl(NULL),
+ _sceneryLoaded("sim/sceneryloaded"),
+ _sceneryLoadOverride("sim/sceneryloaded-override"),
+ _modelHz("sim/model-hz"),
+ _timeDelta("sim/time/delta-realtime-sec"),
+ _simTimeDelta("sim/time/delta-sec")
{
SGCommandMgr::instance()->addCommand("timeofday", do_timeofday);
}
// frame-rate / worst-case latency / update-rate counters
_frameRate = fgGetNode("/sim/frame-rate", true);
_frameLatency = fgGetNode("/sim/frame-latency-max-ms", true);
+ _frameRateWorst = fgGetNode("/sim/frame-rate-worst", true);
_lastFrameTime = 0;
_frameLatencyMax = 0.0;
_frameCount = 0;
_lastClockFreeze = _clockFreeze->getBoolValue();
}
- bool scenery_loaded = fgGetBool("sim/sceneryloaded");
- bool wait_for_scenery = !(scenery_loaded || fgGetBool("sim/sceneryloaded-override"));
-
+ bool wait_for_scenery = !(_sceneryLoaded || _sceneryLoadOverride);
if (!wait_for_scenery) {
throttleUpdateRate();
}
if (0 < dtMax && dtMax < dt) {
dt = dtMax;
}
-
- int model_hz = fgGetInt("/sim/model-hz");
-
+
SGSubsystemGroup* fdmGroup =
globals->get_subsystem_mgr()->get_group(SGSubsystemMgr::FDM);
- fdmGroup->set_fixed_update_time(1.0 / model_hz);
+ fdmGroup->set_fixed_update_time(1.0 / _modelHz);
// round the real time down to a multiple of 1/model-hz.
// this way all systems are updated the _same_ amount of dt.
dt += _dtRemainder;
- int multiLoop = long(floor(dt * model_hz));
+ int multiLoop = long(floor(dt * _modelHz));
multiLoop = SGMisc<long>::max(0, multiLoop);
- _dtRemainder = dt - double(multiLoop)/double(model_hz);
- dt = double(multiLoop)/double(model_hz);
+ _dtRemainder = dt - double(multiLoop)/double(_modelHz);
+ dt = double(multiLoop)/double(_modelHz);
realDt = dt;
if (_clockFreeze->getBoolValue() || wait_for_scenery) {
globals->inc_sim_time_sec(simDt);
// These are useful, especially for Nasal scripts.
- fgSetDouble("/sim/time/delta-realtime-sec", realDt);
- fgSetDouble("/sim/time/delta-sec", simDt);
+ _timeDelta = realDt;
+ _simTimeDelta = simDt;
}
void TimeManager::update(double dt)
if ((_impl->get_cur_time() != _lastFrameTime)) {
_frameRate->setIntValue(_frameCount);
_frameLatency->setDoubleValue(_frameLatencyMax*1000);
+ if (_frameLatencyMax>0)
+ _frameRateWorst->setIntValue(1/_frameLatencyMax);
_frameCount = 0;
_frameLatencyMax = 0.0;
}
void TimeManager::throttleUpdateRate()
{
- double throttle_hz = fgGetDouble("/sim/frame-rate-throttle-hz", 0.0);
- SGTimeStamp currentStamp;
-
// common case, no throttle requested
- if (throttle_hz <= 0.0) {
+ double throttle_hz = fgGetDouble("/sim/frame-rate-throttle-hz", 0.0);
+ if (throttle_hz <= 0)
return; // no-op
- }
-
- double frame_us = 1000000.0 / throttle_hz;
-#define FG_SLEEP_BASED_TIMING 1
-#if defined(FG_SLEEP_BASED_TIMING)
- // sleep based timing loop.
- //
- // Calling sleep, even usleep() on linux is less accurate than
- // we like, but it does free up the cpu for other tasks during
- // the sleep so it is desirable. Because of the way sleep()
- // is implemented in consumer operating systems like windows
- // and linux, you almost always sleep a little longer than the
- // requested amount.
- //
- // To combat the problem of sleeping too long, we calculate the
- // desired wait time and shorten it by 2000us (2ms) to avoid
- // [hopefully] over-sleep'ing. The 2ms value was arrived at
- // via experimentation. We follow this up at the end with a
- // simple busy-wait loop to get the final pause timing exactly
- // right.
- //
- // Assuming we don't oversleep by more than 2000us, this
- // should be a reasonable compromise between sleep based
- // waiting, and busy waiting.
-
- // sleep() will always overshoot by a bit so undersleep by
- // 2000us in the hopes of never oversleeping.
- frame_us -= 2000.0;
- if ( frame_us < 0.0 ) {
- frame_us = 0.0;
- }
-
- currentStamp.stamp();
- double elapsed_us = (currentStamp - _lastStamp).toUSecs();
- if ( elapsed_us < frame_us ) {
- double requested_us = frame_us - elapsed_us;
-
-#ifdef _WIN32
- Sleep ((int)(requested_us / 1000.0)) ;
-#else
- usleep(requested_us) ;
-#endif
- }
-#endif
-
- // busy wait timing loop.
- //
- // This yields the most accurate timing. If the previous
- // ulMilliSecondSleep() call is omitted this will peg the cpu
- // (which is just fine if FG is the only app you care about.)
- currentStamp.stamp();
- SGTimeStamp next_time_stamp = _lastStamp;
- next_time_stamp += SGTimeStamp::fromSec(1e-6*frame_us);
- while ( currentStamp < next_time_stamp ) {
- currentStamp.stamp();
- }
+ // sleep for exactly 1/hz seconds relative to the past valid timestamp
+ SGTimeStamp::sleepUntil(_lastStamp + SGTimeStamp::fromSec(1/throttle_hz));
}
// periodic time updater wrapper
void TimeManager::initTimeOffset()
{
- int offset = fgGetInt("/sim/startup/time-offset");
+ long int offset = fgGetLong("/sim/startup/time-offset");
string offset_type = fgGetString("/sim/startup/time-offset-type");
setTimeOffset(offset_type, offset);
}
-void TimeManager::setTimeOffset(const std::string& offset_type, int offset)
+void TimeManager::setTimeOffset(const std::string& offset_type, long int offset)
{
// Handle potential user specified time offsets
int orig_warp = _warp->getIntValue();
} else if ( offset_type == "noon" ) {
warp = fgTimeSecondsUntilSunAngle( cur_time, lon, lat, 0.0, true );
} else if ( offset_type == "afternoon" ) {
- warp = fgTimeSecondsUntilSunAngle( cur_time, lon, lat, 60.0, false );
+ warp = fgTimeSecondsUntilSunAngle( cur_time, lon, lat, 75.0, false );
} else if ( offset_type == "dusk" ) {
warp = fgTimeSecondsUntilSunAngle( cur_time, lon, lat, 90.0, false );
} else if ( offset_type == "evening" ) {