1 // TimeManager.cxx -- simulation-wide time management
3 // Written by James Turner, started July 2010.
5 // Copyright (C) 2010 Curtis L. Olson - http://www.flightgear.org/~curt
7 // This program is free software; you can redistribute it and/or
8 // modify it under the terms of the GNU General Public License as
9 // published by the Free Software Foundation; either version 2 of the
10 // License, or (at your option) any later version.
12 // This program is distributed in the hope that it will be useful, but
13 // WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 // General Public License for more details.
17 // You should have received a copy of the GNU General Public License
18 // along with this program; if not, write to the Free Software
19 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
25 #include "TimeManager.hxx"
27 #include <simgear/timing/sg_time.hxx>
28 #include <simgear/structure/event_mgr.hxx>
29 #include <simgear/misc/sg_path.hxx>
30 #include <simgear/timing/lowleveltime.h>
31 #include <simgear/structure/commands.hxx>
33 #include <Main/fg_props.hxx>
34 #include <Main/globals.hxx>
35 #include <Time/sunsolver.hxx>
39 static bool do_timeofday (const SGPropertyNode * arg)
41 const string &offset_type = arg->getStringValue("timeofday", "noon");
42 int offset = arg->getIntValue("offset", 0);
43 TimeManager* self = (TimeManager*) globals->get_subsystem("time");
44 if (offset_type == "real") {
45 // without this, setting 'real' time is a no-op, since the current
46 // wrap value (orig_warp) is retained in setTimeOffset. Ick.
47 fgSetInt("/sim/time/warp", 0);
50 self->setTimeOffset(offset_type, offset);
54 TimeManager::TimeManager() :
58 SGCommandMgr::instance()->addCommand("timeofday", do_timeofday);
61 void TimeManager::init()
64 // time manager has to be initialised early, so needs to be defensive
65 // about multiple initialisation
72 _adjustWarpOnUnfreeze = false;
74 _maxDtPerFrame = fgGetNode("/sim/max-simtime-per-frame", true);
75 _clockFreeze = fgGetNode("/sim/freeze/clock", true);
76 _timeOverride = fgGetNode("/sim/time/cur-time-override", true);
77 _warp = fgGetNode("/sim/time/warp", true);
78 _warp->addChangeListener(this);
80 _warpDelta = fgGetNode("/sim/time/warp-delta", true);
82 _longitudeDeg = fgGetNode("/position/longitude-deg", true);
83 _latitudeDeg = fgGetNode("/position/latitude-deg", true);
85 SGPath zone(globals->get_fg_root());
86 zone.append("Timezone");
87 double lon = _longitudeDeg->getDoubleValue() * SG_DEGREES_TO_RADIANS;
88 double lat = _latitudeDeg->getDoubleValue() * SG_DEGREES_TO_RADIANS;
90 _impl = new SGTime(lon, lat, zone.str(), _timeOverride->getLongValue());
92 _warpDelta->setIntValue(0);
94 globals->get_event_mgr()->addTask("updateLocalTime", this,
95 &TimeManager::updateLocalTime, 30*60 );
98 _impl->update(lon, lat, _timeOverride->getLongValue(),
99 _warp->getIntValue());
100 globals->set_time_params(_impl);
102 // frame-rate / worst-case latency / update-rate counters
103 _frameRate = fgGetNode("/sim/frame-rate", true);
104 _frameLatency = fgGetNode("/sim/frame-latency-max-ms", true);
106 _frameLatencyMax = 0.0;
110 void TimeManager::postinit()
115 void TimeManager::reinit()
122 void TimeManager::shutdown()
124 _warp->removeChangeListener(this);
126 globals->set_time_params(NULL);
130 globals->get_event_mgr()->removeTask("updateLocalTime");
133 void TimeManager::valueChanged(SGPropertyNode* aProp)
135 if (aProp == _warp) {
136 if (_clockFreeze->getBoolValue()) {
137 // if the warp is changed manually while frozen, don't modify it when
138 // un-freezing - the user wants to unfreeze with exactly the warp
140 _adjustWarpOnUnfreeze = false;
143 double lon = _longitudeDeg->getDoubleValue() * SG_DEGREES_TO_RADIANS;
144 double lat = _latitudeDeg->getDoubleValue() * SG_DEGREES_TO_RADIANS;
145 _impl->update(lon, lat,
146 _timeOverride->getLongValue(),
147 _warp->getIntValue());
151 void TimeManager::computeTimeDeltas(double& simDt, double& realDt)
153 // Update the elapsed time.
156 _firstUpdate = false;
157 _lastClockFreeze = _clockFreeze->getBoolValue();
160 bool scenery_loaded = fgGetBool("sim/sceneryloaded");
161 bool wait_for_scenery = !(scenery_loaded || fgGetBool("sim/sceneryloaded-override"));
163 if (!wait_for_scenery) {
164 throttleUpdateRate();
168 // suppress framerate while initial scenery isn't loaded yet (splash screen still active)
173 SGTimeStamp currentStamp;
174 currentStamp.stamp();
175 double dt = (currentStamp - _lastStamp).toSecs();
176 if (dt > _frameLatencyMax)
177 _frameLatencyMax = dt;
179 // Limit the time we need to spend in simulation loops
180 // That means, if the /sim/max-simtime-per-frame value is strictly positive
181 // you can limit the maximum amount of time you will do simulations for
182 // one frame to display. The cpu time spent in simulations code is roughly
183 // at least O(real_delta_time_sec). If this is (due to running debug
184 // builds or valgrind or something different blowing up execution times)
185 // larger than the real time you will no longer get any response
186 // from flightgear. This limits that effect. Just set to property from
187 // your .fgfsrc or commandline ...
188 double dtMax = _maxDtPerFrame->getDoubleValue();
189 if (0 < dtMax && dtMax < dt) {
193 int model_hz = fgGetInt("/sim/model-hz");
195 SGSubsystemGroup* fdmGroup =
196 globals->get_subsystem_mgr()->get_group(SGSubsystemMgr::FDM);
197 fdmGroup->set_fixed_update_time(1.0 / model_hz);
199 // round the real time down to a multiple of 1/model-hz.
200 // this way all systems are updated the _same_ amount of dt.
202 int multiLoop = long(floor(dt * model_hz));
203 multiLoop = SGMisc<long>::max(0, multiLoop);
204 _dtRemainder = dt - double(multiLoop)/double(model_hz);
205 dt = double(multiLoop)/double(model_hz);
208 if (_clockFreeze->getBoolValue() || wait_for_scenery) {
214 _lastStamp = currentStamp;
215 globals->inc_sim_time_sec(simDt);
217 // These are useful, especially for Nasal scripts.
218 fgSetDouble("/sim/time/delta-realtime-sec", realDt);
219 fgSetDouble("/sim/time/delta-sec", simDt);
222 void TimeManager::update(double dt)
224 bool freeze = _clockFreeze->getBoolValue();
225 time_t now = time(NULL);
228 // clock freeze requested
229 if (_timeOverride->getLongValue() == 0) {
230 _timeOverride->setLongValue(now);
231 _adjustWarpOnUnfreeze = true;
234 // no clock freeze requested
235 if (_lastClockFreeze) {
236 if (_adjustWarpOnUnfreeze) {
237 // clock just unfroze, let's set warp as the difference
238 // between frozen time and current time so we don't get a
239 // time jump (and corresponding sky object and lighting
241 int adjust = _timeOverride->getLongValue() - now;
242 SG_LOG(SG_GENERAL, SG_INFO, "adjusting on un-freeze:" << adjust);
243 _warp->setIntValue(_warp->getIntValue() + adjust);
245 _timeOverride->setLongValue(0);
248 int warpDelta = _warpDelta->getIntValue();
249 if (warpDelta != 0) {
250 _warp->setIntValue(_warp->getIntValue() + warpDelta);
254 _lastClockFreeze = freeze;
255 double lon = _longitudeDeg->getDoubleValue() * SG_DEGREES_TO_RADIANS;
256 double lat = _latitudeDeg->getDoubleValue() * SG_DEGREES_TO_RADIANS;
257 _impl->update(lon, lat,
258 _timeOverride->getLongValue(),
259 _warp->getIntValue());
264 void TimeManager::computeFrameRate()
266 // Calculate frame rate average
267 if ((_impl->get_cur_time() != _lastFrameTime)) {
268 _frameRate->setIntValue(_frameCount);
269 _frameLatency->setDoubleValue(_frameLatencyMax*1000);
271 _frameLatencyMax = 0.0;
274 _lastFrameTime = _impl->get_cur_time();
278 void TimeManager::throttleUpdateRate()
280 // common case, no throttle requested
281 double throttle_hz = fgGetDouble("/sim/frame-rate-throttle-hz", 0.0);
282 if (throttle_hz <= 0)
285 // sleep for exactly 1/hz seconds relative to the past valid timestamp
286 SGTimeStamp::sleepUntil(_lastStamp + SGTimeStamp::fromSec(1/throttle_hz));
289 // periodic time updater wrapper
290 void TimeManager::updateLocalTime()
292 SGPath zone(globals->get_fg_root());
293 zone.append("Timezone");
295 double lon = _longitudeDeg->getDoubleValue() * SG_DEGREES_TO_RADIANS;
296 double lat = _latitudeDeg->getDoubleValue() * SG_DEGREES_TO_RADIANS;
298 SG_LOG(SG_GENERAL, SG_INFO, "updateLocal(" << lon << ", " << lat << ", " << zone.str() << ")");
299 _impl->updateLocal(lon, lat, zone.str());
302 void TimeManager::initTimeOffset()
305 long int offset = fgGetLong("/sim/startup/time-offset");
306 string offset_type = fgGetString("/sim/startup/time-offset-type");
307 setTimeOffset(offset_type, offset);
310 void TimeManager::setTimeOffset(const std::string& offset_type, long int offset)
312 // Handle potential user specified time offsets
313 int orig_warp = _warp->getIntValue();
314 time_t cur_time = _impl->get_cur_time();
315 time_t currGMT = sgTimeGetGMT( gmtime(&cur_time) );
316 time_t systemLocalTime = sgTimeGetGMT( localtime(&cur_time) );
317 time_t aircraftLocalTime =
318 sgTimeGetGMT( fgLocaltime(&cur_time, _impl->get_zonename() ) );
320 // Okay, we now have several possible scenarios
321 double lon = _longitudeDeg->getDoubleValue() * SG_DEGREES_TO_RADIANS;
322 double lat = _latitudeDeg->getDoubleValue() * SG_DEGREES_TO_RADIANS;
325 if ( offset_type == "real" ) {
327 } else if ( offset_type == "dawn" ) {
328 warp = fgTimeSecondsUntilSunAngle( cur_time, lon, lat, 90.0, true );
329 } else if ( offset_type == "morning" ) {
330 warp = fgTimeSecondsUntilSunAngle( cur_time, lon, lat, 75.0, true );
331 } else if ( offset_type == "noon" ) {
332 warp = fgTimeSecondsUntilSunAngle( cur_time, lon, lat, 0.0, true );
333 } else if ( offset_type == "afternoon" ) {
334 warp = fgTimeSecondsUntilSunAngle( cur_time, lon, lat, 60.0, false );
335 } else if ( offset_type == "dusk" ) {
336 warp = fgTimeSecondsUntilSunAngle( cur_time, lon, lat, 90.0, false );
337 } else if ( offset_type == "evening" ) {
338 warp = fgTimeSecondsUntilSunAngle( cur_time, lon, lat, 100.0, false );
339 } else if ( offset_type == "midnight" ) {
340 warp = fgTimeSecondsUntilSunAngle( cur_time, lon, lat, 180.0, false );
341 } else if ( offset_type == "system-offset" ) {
344 } else if ( offset_type == "gmt-offset" ) {
345 warp = offset - (currGMT - systemLocalTime);
347 } else if ( offset_type == "latitude-offset" ) {
348 warp = offset - (aircraftLocalTime - systemLocalTime);
350 } else if ( offset_type == "system" ) {
351 warp = offset - (systemLocalTime - currGMT) - cur_time;
352 } else if ( offset_type == "gmt" ) {
353 warp = offset - cur_time;
354 } else if ( offset_type == "latitude" ) {
355 warp = offset - (aircraftLocalTime - currGMT)- cur_time;
357 SG_LOG( SG_GENERAL, SG_ALERT,
358 "TimeManager::setTimeOffset: unsupported offset: " << offset_type );
362 _warp->setIntValue( orig_warp + warp );
364 SG_LOG( SG_GENERAL, SG_INFO, "After TimeManager::setTimeOffset(): warp = "
365 << _warp->getIntValue() );