1 // groundnet.cxx - Implimentation of the FlightGear airport ground handling code
3 // Written by Durk Talsma, started June 2005.
5 // Copyright (C) 2004 Durk Talsma.
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.
30 #include <simgear/debug/logstream.hxx>
31 #include <simgear/route/waypoint.hxx>
33 #include <Airports/dynamics.hxx>
35 #include <AIModel/AIFlightPlan.hxx>
37 #include "groundnetwork.hxx"
39 /***************************************************************************
41 **************************************************************************/
43 void FGTaxiSegment::setStart(FGTaxiNodeVector *nodes)
45 FGTaxiNodeVectorIterator i = nodes->begin();
46 while (i != nodes->end())
48 //cerr << "Scanning start node index" << (*i)->getIndex() << endl;
49 if ((*i)->getIndex() == startNode)
51 start = (*i)->getAddress();
52 (*i)->addSegment(this);
57 SG_LOG(SG_GENERAL, SG_ALERT, "Could not find start node " << startNode << endl);
60 void FGTaxiSegment::setEnd(FGTaxiNodeVector *nodes)
62 FGTaxiNodeVectorIterator i = nodes->begin();
63 while (i != nodes->end())
65 //cerr << "Scanning end node index" << (*i)->getIndex() << endl;
66 if ((*i)->getIndex() == endNode)
68 end = (*i)->getAddress();
73 SG_LOG(SG_GENERAL, SG_ALERT, "Could not find end node " << endNode << endl);
78 // There is probably a computationally cheaper way of
80 void FGTaxiSegment::setTrackDistance()
82 length = SGGeodesy::distanceM(start->getGeod(), end->getGeod());
86 void FGTaxiSegment::setCourseDiff(double crse)
88 headingDiff = fabs(course-crse);
90 if (headingDiff > 180)
91 headingDiff = fabs(headingDiff - 360);
95 /***************************************************************************
97 **************************************************************************/
98 bool FGTaxiRoute::next(int *nde)
100 //for (intVecIterator i = nodes.begin(); i != nodes.end(); i++)
101 // cerr << "FGTaxiRoute contains : " << *(i) << endl;
102 //cerr << "Offset from end: " << nodes.end() - currNode << endl;
103 //if (currNode != nodes.end())
104 // cerr << "true" << endl;
106 // cerr << "false" << endl;
107 //if (nodes.size() != (routes.size()) +1)
108 // cerr << "ALERT: Misconfigured TaxiRoute : " << nodes.size() << " " << routes.size() << endl;
110 if (currNode == nodes.end())
113 if (currNode != nodes.begin()) // make sure route corresponds to the end node
119 bool FGTaxiRoute::next(int *nde, int *rte)
121 //for (intVecIterator i = nodes.begin(); i != nodes.end(); i++)
122 // cerr << "FGTaxiRoute contains : " << *(i) << endl;
123 //cerr << "Offset from end: " << nodes.end() - currNode << endl;
124 //if (currNode != nodes.end())
125 // cerr << "true" << endl;
127 // cerr << "false" << endl;
128 if (nodes.size() != (routes.size()) +1) {
129 SG_LOG(SG_GENERAL, SG_ALERT, "ALERT: Misconfigured TaxiRoute : " << nodes.size() << " " << routes.size());
132 if (currNode == nodes.end())
135 //*rte = *(currRoute);
136 if (currNode != nodes.begin()) // Make sure route corresponds to the end node
143 // If currNode points to the first node, this means the aircraft is not on the taxi node
144 // yet. Make sure to return a unique identifyer in this situation though, because otherwise
145 // the speed adjust AI code may be unable to resolve whether two aircraft are on the same
146 // taxi route or not. the negative of the preceding route seems a logical choice, as it is
147 // unique for any starting location.
148 // Note that this is probably just a temporary fix until I get Parking / tower control working.
149 *rte = -1 * *(currRoute);
155 void FGTaxiRoute::rewind(int route)
161 if (!(next(&currPoint, &currRoute))) {
162 SG_LOG(SG_GENERAL,SG_ALERT, "Error in rewinding TaxiRoute: current" << currRoute
163 << " goal " << route);
165 } while (currRoute != route);
171 /***************************************************************************
173 **************************************************************************/
174 bool compare_nodes(FGTaxiNode *a, FGTaxiNode *b) {
178 bool compare_segments(FGTaxiSegment *a, FGTaxiSegment *b) {
182 FGGroundNetwork::FGGroundNetwork()
190 currTraffic = activeTraffic.begin();
194 FGGroundNetwork::~FGGroundNetwork()
196 for (FGTaxiNodeVectorIterator node = nodes.begin();
203 pushBackNodes.clear();
204 for (FGTaxiSegmentVectorIterator seg = segments.begin();
205 seg != segments.end();
213 void FGGroundNetwork::addSegment(const FGTaxiSegment &seg)
215 segments.push_back(new FGTaxiSegment(seg));
218 void FGGroundNetwork::addNode(const FGTaxiNode &node)
220 nodes.push_back(new FGTaxiNode(node));
223 void FGGroundNetwork::addNodes(FGParkingVec *parkings)
226 FGParkingVecIterator i = parkings->begin();
227 while (i != parkings->end())
229 n.setIndex(i->getIndex());
230 n.setLatitude(i->getLatitude());
231 n.setLongitude(i->getLongitude());
232 nodes.push_back(new FGTaxiNode(n));
240 void FGGroundNetwork::init()
244 sort(nodes.begin(), nodes.end(), compare_nodes);
245 //sort(segments.begin(), segments.end(), compare_segments());
246 FGTaxiSegmentVectorIterator i = segments.begin();
247 while(i != segments.end()) {
248 (*i)->setStart(&nodes);
249 (*i)->setEnd (&nodes);
250 (*i)->setTrackDistance();
251 (*i)->setIndex(index);
252 if ((*i)->isPushBack()) {
253 pushBackNodes.push_back((*i)->getEnd());
255 //SG_LOG(SG_GENERAL, SG_BULK, "initializing segment " << (*i)->getIndex() << endl);
256 //SG_LOG(SG_GENERAL, SG_BULK, "Track distance = " << (*i)->getLength() << endl);
257 //SG_LOG(SG_GENERAL, SG_BULK, "Track runs from " << (*i)->getStart()->getIndex() << " to "
258 // << (*i)->getEnd()->getIndex() << endl);
263 i = segments.begin();
264 while(i != segments.end()) {
265 FGTaxiSegmentVectorIterator j = (*i)->getEnd()->getBeginRoute();
266 while (j != (*i)->getEnd()->getEndRoute())
268 if ((*j)->getEnd()->getIndex() == (*i)->getStart()->getIndex())
270 // int start1 = (*i)->getStart()->getIndex();
271 // int end1 = (*i)->getEnd() ->getIndex();
272 // int start2 = (*j)->getStart()->getIndex();
273 // int end2 = (*j)->getEnd()->getIndex();
274 // int oppIndex = (*j)->getIndex();
275 //cerr << "Opposite of " << (*i)->getIndex() << " (" << start1 << "," << end1 << ") "
276 // << "happens to be " << oppIndex << " (" << start2 << "," << end2 << ") " << endl;
277 (*i)->setOpposite(*j);
284 //FGTaxiNodeVectorIterator j = nodes.begin();
285 //while (j != nodes.end()) {
286 // if ((*j)->getHoldPointType() == 3) {
287 // pushBackNodes.push_back((*j));
291 //cerr << "Done initializing ground network" << endl;
295 int FGGroundNetwork::findNearestNode(const SGGeod& aGeod)
297 double minDist = HUGE_VAL;
300 for (FGTaxiNodeVectorIterator itr = nodes.begin(); itr != nodes.end(); itr++)
302 double d = SGGeodesy::distanceM(aGeod, (*itr)->getGeod());
306 index = (*itr)->getIndex();
307 //cerr << "Minimum distance of " << minDist << " for index " << index << endl;
314 int FGGroundNetwork::findNearestNode(double lat, double lon)
316 return findNearestNode(SGGeod::fromDeg(lon, lat));
319 FGTaxiNode *FGGroundNetwork::findNode(unsigned idx)
321 for (FGTaxiNodeVectorIterator
323 itr != nodes.end(); itr++)
325 if (itr->getIndex() == idx)
326 return itr->getAddress();
329 if ((idx >= 0) && (idx < nodes.size()))
330 return nodes[idx]->getAddress();
335 FGTaxiSegment *FGGroundNetwork::findSegment(unsigned idx)
337 for (FGTaxiSegmentVectorIterator
338 itr = segments.begin();
339 itr != segments.end(); itr++)
341 if (itr->getIndex() == idx)
342 return itr->getAddress();
345 if ((idx > 0) && (idx <= segments.size()))
346 return segments[idx-1]->getAddress();
349 //cerr << "Alert: trying to find invalid segment " << idx << endl;
355 FGTaxiRoute FGGroundNetwork::findShortestRoute(int start, int end, bool fullSearch)
357 //implements Dijkstra's algorithm to find shortest distance route from start to end
358 //taken from http://en.wikipedia.org/wiki/Dijkstra's_algorithm
360 //double INFINITE = 100000000000.0;
361 // initialize scoring values
362 int nParkings = parent->getDynamics()->getNrOfParkings();
363 FGTaxiNodeVector *currNodesSet;
365 currNodesSet = &nodes;
367 currNodesSet = &pushBackNodes;
370 for (FGTaxiNodeVectorIterator
371 itr = currNodesSet->begin();
372 itr != currNodesSet->end(); itr++) {
373 (*itr)->setPathScore(HUGE_VAL); //infinity by all practical means
374 (*itr)->setPreviousNode(0); //
375 (*itr)->setPreviousSeg (0); //
378 FGTaxiNode *firstNode = findNode(start);
379 firstNode->setPathScore(0);
381 FGTaxiNode *lastNode = findNode(end);
383 FGTaxiNodeVector unvisited(*currNodesSet); // working copy
385 while (!unvisited.empty()) {
386 FGTaxiNode* best = *(unvisited.begin());
387 for (FGTaxiNodeVectorIterator
388 itr = unvisited.begin();
389 itr != unvisited.end(); itr++) {
390 if ((*itr)->getPathScore() < best->getPathScore())
394 FGTaxiNodeVectorIterator newend = remove(unvisited.begin(), unvisited.end(), best);
395 unvisited.erase(newend, unvisited.end());
397 if (best == lastNode) { // found route or best not connected
400 for (FGTaxiSegmentVectorIterator
401 seg = best->getBeginRoute();
402 seg != best->getEndRoute(); seg++) {
403 if (fullSearch || (*seg)->isPushBack()) {
404 FGTaxiNode* tgt = (*seg)->getEnd();
405 double alt = best->getPathScore() + (*seg)->getLength() + (*seg)->getPenalty(nParkings);
406 if (alt < tgt->getPathScore()) { // Relax (u,v)
407 tgt->setPathScore(alt);
408 tgt->setPreviousNode(best);
409 tgt->setPreviousSeg(*seg); //
412 // // cerr << "Skipping TaxiSegment " << (*seg)->getIndex() << endl;
418 if (lastNode->getPathScore() == HUGE_VAL) {
419 // no valid route found
421 SG_LOG( SG_GENERAL, SG_ALERT, "Failed to find route from waypoint " << start << " to " << end << " at " <<
426 //exit(1); //TODO exit more gracefully, no need to stall the whole sim with broken GN's
428 // assemble route from backtrace information
429 intVec nodes, routes;
430 FGTaxiNode* bt = lastNode;
431 while (bt->getPreviousNode() != 0) {
432 nodes.push_back(bt->getIndex());
433 routes.push_back(bt->getPreviousSegment()->getIndex());
434 bt = bt->getPreviousNode();
436 nodes.push_back(start);
437 reverse(nodes.begin(), nodes.end());
438 reverse(routes.begin(), routes.end());
440 return FGTaxiRoute(nodes, routes, lastNode->getPathScore(), 0);
444 int FGTaxiSegment::getPenalty(int nGates) {
446 if (end->getIndex() < nGates) {
449 if (end->getIsOnRunway()) { // For now. In future versions, need to find out whether runway is active.
455 /* ATC Related Functions */
457 void FGGroundNetwork::announcePosition(int id, FGAIFlightPlan *intendedRoute, int currentPosition,
458 double lat, double lon, double heading,
459 double speed, double alt, double radius, int leg,
460 FGAIAircraft *aircraft)
462 TrafficVectorIterator i = activeTraffic.begin();
463 // Search search if the current id alread has an entry
464 // This might be faster using a map instead of a vector, but let's start by taking a safe route
465 if (activeTraffic.size()) {
466 //while ((i->getId() != id) && i != activeTraffic.end()) {
467 while (i != activeTraffic.end()) {
468 if (i->getId() == id) {
474 // Add a new TrafficRecord if no one exsists for this aircraft.
475 if (i == activeTraffic.end() || (activeTraffic.size() == 0)) {
478 rec.setPositionAndIntentions(currentPosition, intendedRoute);
479 rec.setPositionAndHeading(lat, lon, heading, speed, alt);
480 rec.setRadius(radius); // only need to do this when creating the record.
481 rec.setAircraft(aircraft);
482 activeTraffic.push_back(rec);
484 i->setPositionAndIntentions(currentPosition, intendedRoute);
485 i->setPositionAndHeading(lat, lon, heading, speed, alt);
489 void FGGroundNetwork::signOff(int id) {
490 TrafficVectorIterator i = activeTraffic.begin();
491 // Search search if the current id alread has an entry
492 // This might be faster using a map instead of a vector, but let's start by taking a safe route
493 if (activeTraffic.size()) {
494 //while ((i->getId() != id) && i != activeTraffic.end()) {
495 while (i != activeTraffic.end()) {
496 if (i->getId() == id) {
502 if (i == activeTraffic.end() || (activeTraffic.size() == 0)) {
503 SG_LOG(SG_GENERAL, SG_ALERT, "AI error: Aircraft without traffic record is signing off");
505 i = activeTraffic.erase(i);
509 void FGGroundNetwork::update(int id, double lat, double lon, double heading, double speed, double alt,
511 // Check whether aircraft are on hold due to a preceding pushback. If so, make sure to
512 // Transmit air-to-ground "Ready to taxi request:
513 // Transmit ground to air approval / hold
514 // Transmit confirmation ...
515 // Probably use a status mechanism similar to the Engine start procedure in the startup controller.
518 TrafficVectorIterator i = activeTraffic.begin();
519 // Search search if the current id has an entry
520 // This might be faster using a map instead of a vector, but let's start by taking a safe route
521 TrafficVectorIterator current, closest;
522 if (activeTraffic.size()) {
523 //while ((i->getId() != id) && i != activeTraffic.end()) {
524 while (i != activeTraffic.end()) {
525 if (i->getId() == id) {
531 // update position of the current aircraft
532 if (i == activeTraffic.end() || (activeTraffic.size() == 0)) {
533 SG_LOG(SG_GENERAL, SG_ALERT, "AI error: updating aircraft without traffic record");
535 i->setPositionAndHeading(lat, lon, heading, speed, alt);
541 // Update every three secs, but add some randomness
542 // to prevent all IA objects doing this in synchrony
543 //if (getDt() < (3.0) + (rand() % 10))
547 current->clearResolveCircularWait();
548 current->setWaitsForId(0);
549 checkSpeedAdjustment(id, lat, lon, heading, speed, alt);
550 checkHoldPosition (id, lat, lon, heading, speed, alt);
551 if (checkForCircularWaits(id)) {
552 i->setResolveCircularWait();
557 Scan for a speed adjustment change. Find the nearest aircraft that is in front
558 and adjust speed when we get too close. Only do this when current position and/or
559 intentions of the current aircraft match current taxiroute position of the proximate
560 aircraft. For traffic that is on other routes we need to issue a "HOLD Position"
561 instruction. See below for the hold position instruction.
563 Note that there currently still is one flaw in the logic that needs to be addressed.
564 There can be situations where one aircraft is in front of the current aircraft, on a separate
565 route, but really close after an intersection coming off the current route. This
566 aircraft is still close enough to block the current aircraft. This situation is currently
567 not addressed yet, but should be.
570 void FGGroundNetwork::checkSpeedAdjustment(int id, double lat,
571 double lon, double heading,
572 double speed, double alt)
575 TrafficVectorIterator current, closest;
576 TrafficVectorIterator i = activeTraffic.begin();
577 bool otherReasonToSlowDown = false;
578 bool previousInstruction;
579 if (activeTraffic.size())
581 //while ((i->getId() != id) && (i != activeTraffic.end()))
582 while (i != activeTraffic.end()) {
583 if (i->getId() == id) {
593 if (i == activeTraffic.end() || (activeTraffic.size() == 0)) {
594 SG_LOG(SG_GENERAL, SG_ALERT, "AI error: Trying to access non-existing aircraft in FGGroundNetwork::checkSpeedAdjustment");
599 previousInstruction = current->getSpeedAdjustment();
600 double mindist = HUGE_VAL;
601 if (activeTraffic.size())
603 double course, dist, bearing, minbearing, az2;
604 SGGeod curr(SGGeod::fromDegM(lon, lat, alt));
605 //TrafficVector iterator closest;
607 for (TrafficVectorIterator i = activeTraffic.begin();
608 i != activeTraffic.end(); i++)
614 SGGeod other(SGGeod::fromDegM(i->getLongitude(),
615 i->getLatitude(), i->getAltitude()));
616 SGGeodesy::inverse(curr, other, course, az2, dist);
617 bearing = fabs(heading-course);
619 bearing = 360-bearing;
620 if ((dist < mindist) && (bearing < 60.0))
624 minbearing = bearing;
627 //Check traffic at the tower controller
628 if (towerController->hasActiveTraffic())
630 for (TrafficVectorIterator i = towerController->getActiveTraffic().begin();
631 i != towerController->getActiveTraffic().end(); i++)
633 //cerr << "Comparing " << current->getId() << " and " << i->getId() << endl;
634 SGGeod other(SGGeod::fromDegM(i->getLongitude(),
637 SGGeodesy::inverse(curr, other, course, az2, dist);
638 bearing = fabs(heading-course);
640 bearing = 360-bearing;
641 if ((dist < mindist) && (bearing < 60.0))
645 minbearing = bearing;
646 otherReasonToSlowDown = true;
650 // Finally, check UserPosition
651 double userLatitude = fgGetDouble("/position/latitude-deg");
652 double userLongitude = fgGetDouble("/position/longitude-deg");
653 SGGeod user(SGGeod::fromDeg(userLongitude,userLatitude));
654 SGGeodesy::inverse(curr, user, course, az2, dist);
656 bearing = fabs(heading-course);
658 bearing = 360-bearing;
659 if ((dist < mindist) && (bearing < 60.0))
663 minbearing = bearing;
664 otherReasonToSlowDown = true;
667 current->clearSpeedAdjustment();
669 if (current->checkPositionAndIntentions(*closest) || otherReasonToSlowDown)
671 double maxAllowableDistance = (1.1*current->getRadius()) + (1.1*closest->getRadius());
672 if (mindist < 2*maxAllowableDistance)
674 if (current->getId() == closest->getWaitsForId())
677 current->setWaitsForId(closest->getId());
678 if (closest->getId() != current->getId())
679 current->setSpeedAdjustment(closest->getSpeed()* (mindist/100));
681 current->setSpeedAdjustment(0); // This can only happen when the user aircraft is the one closest
682 if (mindist < maxAllowableDistance)
684 //double newSpeed = (maxAllowableDistance-mindist);
685 //current->setSpeedAdjustment(newSpeed);
686 //if (mindist < 0.5* maxAllowableDistance)
688 current->setSpeedAdjustment(0);
697 Check for "Hold position instruction".
698 The hold position should be issued under the following conditions:
699 1) For aircraft entering or crossing a runway with active traffic on it, or landing aircraft near it
700 2) For taxiing aircraft that use one taxiway in opposite directions
701 3) For crossing or merging taxiroutes.
704 void FGGroundNetwork::checkHoldPosition(int id, double lat,
705 double lon, double heading,
706 double speed, double alt)
709 TrafficVectorIterator current;
710 TrafficVectorIterator i = activeTraffic.begin();
711 if (activeTraffic.size())
713 //while ((i->getId() != id) && i != activeTraffic.end())
714 while (i != activeTraffic.end()) {
715 if (i->getId() == id) {
725 if (i == activeTraffic.end() || (activeTraffic.size() == 0)) {
726 SG_LOG(SG_GENERAL, SG_ALERT, "AI error: Trying to access non-existing aircraft in FGGroundNetwork::checkHoldPosition");
729 current->setHoldPosition(false);
730 SGGeod curr(SGGeod::fromDegM(lon, lat, alt));
732 for (i = activeTraffic.begin();
733 i != activeTraffic.end(); i++)
735 if (i->getId() != current->getId())
737 int node = current->crosses(this, *i);
740 FGTaxiNode* taxiNode = findNode(node);
742 // Determine whether it's save to continue or not.
743 // If we have a crossing route, there are two possibilities:
744 // 1) This is an interestion
745 // 2) This is oncoming two-way traffic, using the same taxiway.
746 //cerr << "Hold check 1 : " << id << " has common node " << node << endl;
748 SGGeod other(SGGeod::fromDegM(i->getLongitude(), i->getLatitude(), i->getAltitude()));
751 if (current->isOpposing(this, *i, node))
755 //cerr << "Hold check 2 : " << node << " has opposing segment " << endl;
756 // issue a "Hold Position" as soon as we're close to the offending node
757 // For now, I'm doing this as long as the other aircraft doesn't
758 // have a hold instruction as soon as we're within a reasonable
759 // distance from the offending node.
760 // This may be a bit of a conservative estimate though, as it may
761 // be well possible that both aircraft can both continue to taxi
762 // without crashing into each other.
767 if (SGGeodesy::distanceM(other, taxiNode->getGeod()) > 200) // 2.0*i->getRadius())
770 //cerr << "Hold check 3 : " << id <<" Other aircraft approaching node is still far away. (" << dist << " nm). Can safely continue "
776 //cerr << "Hold check 4: " << id << " Would need to wait for other aircraft : distance = " << dist << " meters" << endl;
780 double dist = SGGeodesy::distanceM(curr, taxiNode->getGeod());
781 if (!(i->hasHoldPosition()))
784 if ((dist < 200) && //2.5*current->getRadius()) &&
786 (i->onRoute(this, *current)) &&
787 //((i->onRoute(this, *current)) || ((!(i->getSpeedAdjustment())))) &&
788 (!(current->getId() == i->getWaitsForId())))
789 //(!(i->getSpeedAdjustment()))) // &&
790 //(!(current->getSpeedAdjustment())))
793 current->setHoldPosition(true);
794 current->setWaitsForId(i->getId());
795 //cerr << "Hold check 5: " << current->getCallSign() <<" Setting Hold Position: distance to node (" << node << ") "
796 // << dist << " meters. Waiting for " << i->getCallSign();
798 //cerr <<" [opposing] " << endl;
800 // cerr << "[non-opposing] " << endl;
801 //if (i->hasSpeefAdjustment())
803 // cerr << " (which in turn waits for ) " << i->
807 //cerr << "Hold check 6: " << id << " No need to hold yet: Distance to node : " << dist << " nm"<< endl;
816 * Check whether situations occur where the current aircraft is waiting for itself
817 * due to higher order interactions.
818 * A 'circular' wait is a situation where a waits for b, b waits for c, and c waits
819 * for a. Ideally each aircraft only waits for one other aircraft, so by tracing
820 * through this list of waiting aircraft, we can check if we'd eventually end back
821 * at the current aircraft.
823 * Note that we should consider the situation where we are actually checking aircraft
824 * d, which is waiting for aircraft a. d is not part of the loop, but is held back by
825 * the looping aircraft. If we don't check for that, this function will get stuck into
829 bool FGGroundNetwork::checkForCircularWaits(int id)
831 //cerr << "Performing Wait check " << id << endl;
833 TrafficVectorIterator current, other;
834 TrafficVectorIterator i = activeTraffic.begin();
835 int trafficSize = activeTraffic.size();
837 while (i != activeTraffic.end()) {
838 if (i->getId() == id) {
847 if (i == activeTraffic.end() || (trafficSize == 0)) {
848 SG_LOG(SG_GENERAL, SG_ALERT, "AI error: Trying to access non-existing aircraft in FGGroundNetwork::checkForCircularWaits");
852 target = current->getWaitsForId();
853 //bool printed = false; // Note that this variable is for debugging purposes only.
857 //cerr << "aircraft waits for user" << endl;
862 while ((target > 0) && (target != id) && counter++ < trafficSize) {
864 TrafficVectorIterator i = activeTraffic.begin();
866 //while ((i->getId() != id) && i != activeTraffic.end())
867 while (i != activeTraffic.end()) {
868 if (i->getId() == target) {
877 if (i == activeTraffic.end() || (trafficSize == 0)) {
878 //cerr << "[Waiting for traffic at Runway: DONE] " << endl << endl;;
879 // The target id is not found on the current network, which means it's at the tower
880 //SG_LOG(SG_GENERAL, SG_ALERT, "AI error: Trying to access non-existing aircraft in FGGroundNetwork::checkForCircularWaits");
884 target = other->getWaitsForId();
886 // actually this trap isn't as impossible as it first seemed:
887 // the setWaitsForID(id) is set to current when the aircraft
888 // is waiting for the user controlled aircraft.
889 //if (current->getId() == other->getId()) {
890 // cerr << "Caught the impossible trap" << endl;
891 // cerr << "Current = " << current->getId() << endl;
892 // cerr << "Other = " << other ->getId() << endl;
893 // for (TrafficVectorIterator at = activeTraffic.begin();
894 // at != activeTraffic.end();
896 // cerr << "currently active aircraft : " << at->getCallSign() << " with Id " << at->getId() << " waits for " << at->getWaitsForId() << endl;
899 if (current->getId() == other->getId())
902 //cerr << current->getCallSign() << " (" << current->getId() << ") " << " -> " << other->getCallSign()
903 // << " (" << other->getId() << "); " << endl;;
913 // cerr << "[done] " << endl << endl;;
915 SG_LOG(SG_GENERAL, SG_WARN, "Detected circular wait condition: Id = " << id << "target = " << target);
922 // Note that this function is probably obsolete...
923 bool FGGroundNetwork::hasInstruction(int id)
925 TrafficVectorIterator i = activeTraffic.begin();
926 // Search search if the current id has an entry
927 // This might be faster using a map instead of a vector, but let's start by taking a safe route
928 if (activeTraffic.size())
930 //while ((i->getId() != id) && i != activeTraffic.end()) {
931 while (i != activeTraffic.end()) {
932 if (i->getId() == id) {
938 if (i == activeTraffic.end() || (activeTraffic.size() == 0)) {
939 SG_LOG(SG_GENERAL, SG_ALERT, "AI error: checking ATC instruction for aircraft without traffic record");
941 return i->hasInstruction();
946 FGATCInstruction FGGroundNetwork::getInstruction(int id)
948 TrafficVectorIterator i = activeTraffic.begin();
949 // Search search if the current id has an entry
950 // This might be faster using a map instead of a vector, but let's start by taking a safe route
951 if (activeTraffic.size()) {
952 //while ((i->getId() != id) && i != activeTraffic.end()) {
953 while (i != activeTraffic.end()) {
954 if (i->getId() == id) {
960 if (i == activeTraffic.end() || (activeTraffic.size() == 0)) {
961 SG_LOG(SG_GENERAL, SG_ALERT, "AI error: requesting ATC instruction for aircraft without traffic record");
963 return i->getInstruction();
965 return FGATCInstruction();