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Further progress towards interactive tower control. Very much an initial stab at a first iteration of a tricky problem, ie don't look too closely - some of it is ugly!

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This commit is contained in:
daveluff 2003-09-19 16:51:27 +00:00
parent bac252c23d
commit 6e73e7dc08
2 changed files with 411 additions and 53 deletions
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421
src/ATC/tower.cxx
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@ -43,6 +43,8 @@ longFinalReported(false),
longFinalAcknowledged(false),
finalReported(false),
finalAcknowledged(false),
onRwy(false),
nextOnRwy(false),
opType(TTT_UNKNOWN),
leg(LEG_UNKNOWN),
isUser(false)
@ -59,6 +61,8 @@ longFinalReported(false),
longFinalAcknowledged(false),
finalReported(false),
finalAcknowledged(false),
onRwy(false),
nextOnRwy(false),
opType(TTT_UNKNOWN),
leg(LEG_UNKNOWN),
isUser(false)
@ -75,6 +79,8 @@ longFinalReported(false),
longFinalAcknowledged(false),
finalReported(false),
finalAcknowledged(false),
onRwy(false),
nextOnRwy(false),
opType(TTT_UNKNOWN),
leg(LEG_UNKNOWN),
isUser(false)
@ -92,6 +98,8 @@ longFinalReported(false),
longFinalAcknowledged(false),
finalReported(false),
finalAcknowledged(false),
onRwy(false),
nextOnRwy(false),
opType(TTT_UNKNOWN),
leg(LEG_UNKNOWN),
isUser(false)
@ -116,6 +124,8 @@ FGTower::FGTower() {
rwyListItr = rwyList.begin();
circuitListItr = circuitList.begin();
trafficListItr = trafficList.begin();
freqClear = true;
}
FGTower::~FGTower() {
@ -192,6 +202,7 @@ void FGTower::Init() {
// Assume the user is started at the threshold ready to take-off
TowerPlaneRec* t = new TowerPlaneRec;
t->plane.callsign = "Charlie Foxtrot Sierra"; // C-FGFS !!! - fixme - this is a bit hardwired
t->plane.type = GA_SINGLE;
t->opType = TTT_UNKNOWN; // We don't know if the user wants to do circuits or a departure...
t->leg = TAKEOFF_ROLL;
t->isUser = true;
@ -258,9 +269,79 @@ void FGTower::Update(double dt) {
t->planePtr->RegisterTransmission(3); // cleared to line-up
t->leg = TAKEOFF_ROLL;
//} else if(arriving plane < some threshold away) {
} else if(0) { // FIXME
} else if(GetTrafficETA(2) < 150.0) {
trns += " cleared immediate take-off";
// TODO - add traffic is... ?
if(trafficList.size()) {
tower_plane_rec_list_iterator trfcItr = trafficList.begin();
trfcItr++; // At the moment the holding plane should be first in trafficList.
// Note though that this will break if holding planes aren't put in trafficList in the future.
TowerPlaneRec* trfc = *trfcItr;
trns += "... traffic is";
switch(trfc->plane.type) {
case UNKNOWN:
break;
case GA_SINGLE:
trns += " a Cessna"; // TODO - add ability to specify actual plane type somewhere
break;
case GA_HP_SINGLE:
trns += " a Piper";
break;
case GA_TWIN:
trns += " a King-air";
break;
case GA_JET:
trns += " a Learjet";
break;
case MEDIUM:
trns += " a Regional";
break;
case HEAVY:
trns += " a Heavy";
break;
case MIL_JET:
trns += " Military";
break;
}
if(trfc->opType == STRAIGHT_IN || trfc->opType == TTT_UNKNOWN) {
double miles_out = CalcDistOutMiles(trfc);
if(miles_out < 2) {
trns += " on final";
} else {
trns += " on ";
trns += ConvertNumToSpokenDigits((int)miles_out);
trns += " mile final";
}
} else if(trfc->opType == CIRCUIT) {
switch(trfc->leg) {
case FINAL:
trns += " on final";
break;
case TURN4:
trns += " turning final";
break;
case BASE:
trns += " on base";
break;
case TURN3:
trns += " turning base";
break;
case DOWNWIND:
trns += " in circuit";
break;
// And to eliminate compiler warnings...
case TAKEOFF_ROLL: break;
case CLIMBOUT: break;
case TURN1: break;
case CROSSWIND: break;
case TURN2: break;
case LANDING_ROLL: break;
case LEG_UNKNOWN: break;
}
}
} else {
// By definition there should be some arriving traffic if we're cleared for immediate takeoff
SG_LOG(SG_ATC, SG_WARN, "Warning: Departing traffic cleared for *immediate* take-off despite no arriving traffic in FGTower");
}
t->clearedToTakeOff = true;
t->planePtr->RegisterTransmission(4); // cleared to take-off - TODO differentiate between immediate and normal take-off
t->leg = TAKEOFF_ROLL;
@ -282,17 +363,64 @@ void FGTower::Update(double dt) {
holdListItr = holdList.begin();
}
} else {
// possibly tell him to hold and what position he is?
// Tell him to hold and what position he is.
// Not currently sure under which circumstances we do or don't bother transmitting this.
string trns = t->plane.callsign;
trns += " hold position";
if(display) {
globals->get_ATC_display()->RegisterSingleMessage(trns, 0);
}
t->holdShortReported = false;
t->clearanceCounter = 0;
// TODO - add some idea of what traffic is blocking him.
}
} else {
t->clearanceCounter += (dt * holdList.size() * ii_max);
}
}
} else { // not responding to report, but still need to clear if clear
if(t->nextOnRwy) {
if(rwyOccupied) {
// Do nothing for now - consider acknowloging hold short eventually
} else {
// Lets Roll !!!!
string trns = t->plane.callsign;
//if(departed plane < some threshold in time away) {
if(0) { // FIXME
trns += " line up";
t->clearedToLineUp = true;
t->planePtr->RegisterTransmission(3); // cleared to line-up
t->leg = TAKEOFF_ROLL;
//} else if(arriving plane < some threshold away) {
} else if(GetTrafficETA(2) < 150.0) {
trns += " cleared immediate take-off";
// TODO - add traffic is... ?
t->clearedToTakeOff = true;
t->planePtr->RegisterTransmission(4); // cleared to take-off - TODO differentiate between immediate and normal take-off
t->leg = TAKEOFF_ROLL;
} else {
trns += " cleared for take-off";
// TODO - add traffic is... ?
t->clearedToTakeOff = true;
t->planePtr->RegisterTransmission(4); // cleared to take-off
t->leg = TAKEOFF_ROLL;
}
if(display) {
globals->get_ATC_display()->RegisterSingleMessage(trns, 0);
}
rwyList.push_back(t);
rwyOccupied = true;
holdList.erase(holdListItr);
holdListItr = holdList.begin();
}
}
// TODO - remove the considerable code duplication above!
}
++holdListItr;
}
}
// Do the runway list - we'll do the whole runway list since it's important and there'll never be many planes on the rwy at once!!
// FIXME - at the moment it looks like we're only doing the first plane from the rwy list.
if(ii == 5) {
if(rwyOccupied) {
if(!rwyList.size()) {
@ -313,10 +441,14 @@ void FGTower::Update(double dt) {
rwyList.pop_front();
} else if(t->opType == CIRCUIT) {
circuitList.push_back(t);
//cout << "Oggy oggy oggy\n";
AddToTrafficList(t);
rwyList.pop_front();
} else if(t->opType == TTT_UNKNOWN) {
depList.push_back(t);
circuitList.push_back(t);
//cout << "Aggy aggy aggy\n";
AddToTrafficList(t);
rwyList.pop_front();
} else {
// HELP - we shouldn't ever get here!!!
@ -365,9 +497,10 @@ void FGTower::Update(double dt) {
if(t->opType == TTT_UNKNOWN) {
if(tortho.y() > 5000) {
// 5 km out from threshold - assume it's a departure
t->opType = OUTBOUND;
t->opType = OUTBOUND; // TODO - could check if the user has climbed significantly above circuit altitude as well.
// Since we are unknown operation we should be in depList already.
circuitList.erase(circuitListItr);
RemoveFromTrafficList(t->plane.callsign);
circuitListItr = circuitList.begin();
}
} else if(t->opType == CIRCUIT) {
@ -408,6 +541,8 @@ void FGTower::Update(double dt) {
//cout << "Turn2\n";
} else {
t->leg = TURN3;
// Probably safe now to assume the user is flying a circuit
t->opType = CIRCUIT;
//cout << "Turn3\n";
}
} else {
@ -464,6 +599,29 @@ void FGTower::Update(double dt) {
}
}
// Do one plane from the approach list
if(ii == 7) {
if(appList.size()) {
if(appListItr == appList.end()) {
appListItr = appList.begin();
}
TowerPlaneRec* t = *appListItr;
//cout << "t = " << t << endl;
if(t->isUser) {
t->pos.setlon(user_lon_node->getDoubleValue());
t->pos.setlat(user_lat_node->getDoubleValue());
t->pos.setelev(user_elev_node->getDoubleValue());
} else {
// TODO - set/update the position if it's an AI plane
}
if(t->nextOnRwy && !(t->clearedToLand)) {
// check distance away and whether runway occupied
// and schedule transmission if necessary
}
++appListItr;
}
}
doCommunication();
if(!separateGround) {
@ -633,71 +791,198 @@ bool FGTower::OnAnyRunway(Point3D pt) {
}
// Calculate the eta of each plane to the threshold.
// Returns true if successful
bool FGTower::RemoveFromTrafficList(string id) {
tower_plane_rec_list_iterator twrItr;
for(twrItr = trafficList.begin(); twrItr != trafficList.end(); twrItr++) {
TowerPlaneRec* tpr = *twrItr;
if(tpr->plane.callsign == id) {
trafficList.erase(twrItr);
return(true);
}
}
SG_LOG(SG_ATC, SG_WARN, "Warning - unable to remove aircraft " << id << " from trafficList in FGTower");
return(false);
}
// Add a tower plane rec with ETA to the traffic list in the correct position ETA-wise
// and set nextOnRwy if so.
// Returns true if this could cause a threshold ETA conflict with other traffic, false otherwise.
// For planes holding they are put in the first position with time to go, and the return value is
// true if in the first position (nextOnRwy) and false otherwise.
bool FGTower::AddToTrafficList(TowerPlaneRec* t, bool holding) {
//cout << "AddToTrafficList called, currently size = " << trafficList.size() << ", holding = " << holding << '\n';
double separation_time = 90.0; // seconds - this is currently a guess for light plane separation, and includes a few seconds for a holding plane to taxi onto the rwy.
bool conflict = false;
double lastETA = 0.0;
bool firstTime = true;
// FIXME - make this more robust for different plane types eg. light following heavy.
tower_plane_rec_list_iterator twrItr;
for(twrItr = trafficList.begin(); twrItr != trafficList.end(); twrItr++) {
TowerPlaneRec* tpr = *twrItr;
if(holding) {
//cout << (tpr->isUser ? "USER!\n" : "NOT user\n");
//cout << "tpr->eta - lastETA = " << tpr->eta - lastETA << '\n';
if(tpr->eta - lastETA > separation_time) {
t->nextOnRwy = firstTime;
trafficList.insert(twrItr, t);
return(firstTime);
}
firstTime = false;
} else {
if(t->eta < tpr->eta) {
// Ugg - this one's tricky.
// It depends on what the two planes are doing and whether there's a conflict what we do.
if(tpr->eta - t->eta > separation_time) { // No probs, plane 2 can squeeze in before plane 1 with no apparent conflict
if(tpr->nextOnRwy) {
tpr->nextOnRwy = false;
t->nextOnRwy = true;
}
trafficList.insert(twrItr, t);
} else { // Ooops - this ones tricky - we have a potential conflict!
conflict = true;
}
return(conflict);
}
}
}
// If we get here we must be at the end of the list, or maybe the list is empty.
if(!trafficList.size()) {
t->nextOnRwy = true;
// conflict and firstTime should be false and true respectively in this case anyway.
}
trafficList.push_back(t);
return(holding ? firstTime : conflict);
}
// Calculate the eta of a plane to the threshold.
// For ground traffic this is the fastest they can get there.
// For air traffic this is the middle approximation.
void FGTower::doThresholdETACalc() {
void FGTower::CalcETA(TowerPlaneRec* tpr) {
// For now we'll be very crude and hardwire expected speeds to C172-like values
// The speeds below are specified in knots IAS and then converted to m/s
double app_ias = 100.0 * 0.514444; // Speed during straight-in approach
double circuit_ias = 80.0 * 0.514444; // Speed around circuit
double final_ias = 70.0 * 0.514444; // Speed during final approach
tower_plane_rec_list_iterator twrItr;
// Sign convention - dist_out is -ve for approaching planes and +ve for departing planes
// dist_across is +ve in the pattern direction - ie a plane correctly on downwind will have a +ve dist_across
for(twrItr = trafficList.begin(); twrItr != trafficList.end(); twrItr++) {
TowerPlaneRec* tpr = *twrItr;
Point3D op = ortho.ConvertToLocal(tpr->pos);
double dist_out_m = op.y();
double dist_across_m = fabs(op.x()); // FIXME = the fabs is a hack to cope with the fact that we don't know the circuit direction yet
//cout << "Doing ETA calc for " << tpr->plane.callsign << '\n';
if(tpr->opType == CIRCUIT) {
// It's complicated - depends on if base leg is delayed or not
if(tpr->leg == LANDING_ROLL) {
tpr->eta = 0;
} else if((tpr->leg == FINAL) || (tpr->leg == TURN4)) {
tpr->eta = fabs(dist_out_m) / final_ias;
} else if((tpr->leg == BASE) || (tpr->leg == TURN3)) {
tpr->eta = (fabs(dist_out_m) / final_ias) + (dist_across_m / circuit_ias);
} else {
// Need to calculate where base leg is likely to be
// FIXME - for now I'll hardwire it to 1000m which is what AILocalTraffic uses!!!
// TODO - as a matter of design - AILocalTraffic should get the nominal no-traffic base turn distance from Tower, since in real life the published pattern might differ from airport to airport
double nominal_base_dist_out_m = -1000;
double current_base_dist_out_m = nominal_base_dist_out_m;
double nominal_dist_across_m = 1000; // Hardwired value from AILocalTraffic
double nominal_cross_dist_out_m = 1000; // Bit of a guess - AI plane turns to crosswind at 600ft agl.
tpr->eta = fabs(current_base_dist_out_m) / final_ias; // final
if((tpr->leg == DOWNWIND) || (tpr->leg == TURN2)) {
tpr->eta += dist_across_m / circuit_ias;
tpr->eta += fabs(current_base_dist_out_m - dist_out_m) / circuit_ias;
} else if((tpr->leg == CROSSWIND) || (tpr->leg == TURN1)) {
tpr->eta += nominal_dist_across_m / circuit_ias; // should we use the dist across of the previous plane if there is previous still on downwind?
tpr->eta += fabs(current_base_dist_out_m - nominal_cross_dist_out_m) / circuit_ias;
tpr->eta += (nominal_dist_across_m - dist_across_m) / circuit_ias;
} else {
// We've only just started - why not use a generic estimate?
}
}
} else if((tpr->opType == INBOUND) || (tpr->opType == STRAIGHT_IN)) {
// It's simpler!
Point3D op = ortho.ConvertToLocal(tpr->pos);
double dist_out_m = op.y();
double dist_across_m = fabs(op.x()); // FIXME = the fabs is a hack to cope with the fact that we don't know the circuit direction yet
//cout << "Doing ETA calc for " << tpr->plane.callsign << '\n';
if(tpr->opType == STRAIGHT_IN) {
double dist_to_go_m = sqrt((dist_out_m * dist_out_m) + (dist_across_m * dist_across_m));
if(dist_to_go_m < 1000) {
tpr->eta = dist_to_go_m / final_ias;
} else {
// Must be outbound - ignore it!
tpr->eta = (1000.0 / final_ias) + ((dist_to_go_m - 1000.0) / app_ias);
}
} else if(tpr->opType == CIRCUIT || tpr->opType == TTT_UNKNOWN) { // Hack alert - UNKNOWN has sort of been added here as a temporary hack.
// It's complicated - depends on if base leg is delayed or not
if(tpr->leg == LANDING_ROLL) {
tpr->eta = 0;
} else if((tpr->leg == FINAL) || (tpr->leg == TURN4)) {
tpr->eta = fabs(dist_out_m) / final_ias;
} else if((tpr->leg == BASE) || (tpr->leg == TURN3)) {
tpr->eta = (fabs(dist_out_m) / final_ias) + (dist_across_m / circuit_ias);
} else {
// Need to calculate where base leg is likely to be
// FIXME - for now I'll hardwire it to 1000m which is what AILocalTraffic uses!!!
// TODO - as a matter of design - AILocalTraffic should get the nominal no-traffic base turn distance from Tower, since in real life the published pattern might differ from airport to airport
double nominal_base_dist_out_m = -1000;
double current_base_dist_out_m;
if(!GetBaseConstraint(current_base_dist_out_m)) {
current_base_dist_out_m = nominal_base_dist_out_m;
}
double nominal_dist_across_m = 1000; // Hardwired value from AILocalTraffic
double current_dist_across_m;
if(!GetDownwindConstraint(current_dist_across_m)) {
current_dist_across_m = nominal_dist_across_m;
}
double nominal_cross_dist_out_m = 1000; // Bit of a guess - AI plane turns to crosswind at 600ft agl.
tpr->eta = fabs(current_base_dist_out_m) / final_ias; // final
if((tpr->leg == DOWNWIND) || (tpr->leg == TURN2)) {
tpr->eta += dist_across_m / circuit_ias;
tpr->eta += fabs(current_base_dist_out_m - dist_out_m) / circuit_ias;
} else if((tpr->leg == CROSSWIND) || (tpr->leg == TURN1)) {
tpr->eta += nominal_dist_across_m / circuit_ias; // should we use the dist across of the previous plane if there is previous still on downwind?
tpr->eta += fabs(current_base_dist_out_m - nominal_cross_dist_out_m) / circuit_ias;
tpr->eta += (nominal_dist_across_m - dist_across_m) / circuit_ias;
} else {
// We've only just started - why not use a generic estimate?
}
}
//cout << "ETA = " << tpr->eta << '\n';
} else {
tpr->eta = 99999;
}
}
// Calculate the distance of a plane to the threshold in meters
// TODO - Modify to calculate flying distance of a plane in the circuit
double FGTower::CalcDistOutM(TowerPlaneRec* tpr) {
return(dclGetHorizontalSeparation(rwy.threshold_pos, tpr->pos));
}
// Calculate the distance of a plane to the threshold in miles
// TODO - Modify to calculate flying distance of a plane in the circuit
double FGTower::CalcDistOutMiles(TowerPlaneRec* tpr) {
return(CalcDistOutM(tpr) / 1600.0); // FIXME - use a proper constant if possible.
}
// Iterate through all the lists and call CalcETA for all the planes.
void FGTower::doThresholdETACalc() {
tower_plane_rec_list_iterator twrItr;
// Do the approach list first
for(twrItr = appList.begin(); twrItr != appList.end(); twrItr++) {
TowerPlaneRec* tpr = *twrItr;
CalcETA(tpr);
}
// Then the circuit list
for(twrItr = circuitList.begin(); twrItr != circuitList.end(); twrItr++) {
TowerPlaneRec* tpr = *twrItr;
CalcETA(tpr);
}
}
// Check that the planes in traffic list are correctly ordered,
// that the nearest (timewise) is flagged next on rwy, and return
// true if any threshold use conflicts are detected, false otherwise.
bool FGTower::doThresholdUseOrder() {
return(true);
bool conflict = false;
// TODO - write some code here!
return(conflict);
}
void FGTower::doCommunication() {
}
// Return the ETA of plane no. list_pos (1-based) in the traffic list.
// i.e. list_pos = 1 implies next to use runway.
double FGTower::GetTrafficETA(unsigned int list_pos) {
if(trafficList.size() < list_pos) {
return(99999);
}
tower_plane_rec_list_iterator twrItr;
twrItr = trafficList.begin();
for(unsigned int i = 1; i < list_pos; i++, twrItr++);
//cout << "ETA returned = " << (*twrItr)->eta << '\n';
return((*twrItr)->eta);
}
void FGTower::ContactAtHoldShort(PlaneRec plane, FGAIPlane* requestee, tower_traffic_type operation) {
// HACK - assume that anything contacting at hold short is new for now - FIXME LATER
TowerPlaneRec* t = new TowerPlaneRec;
@ -709,8 +994,20 @@ void FGTower::ContactAtHoldShort(PlaneRec plane, FGAIPlane* requestee, tower_tra
t->clearedToTakeOff = false;
t->opType = operation;
// HACK ALERT - THIS IS HARDWIRED FOR TESTING - FIXME TODO ETC
t->nextOnRwy = true;
//cout << "Hold Short reported by " << plane.callsign << '\n';
bool next = AddToTrafficList(t, true);
if(next) {
//cout << "Next to take off - respond with clearance\n";
double teta = GetTrafficETA(2);
if(teta < 150.0) {
t->clearanceCounter = 7.0; // This reduces the delay before response to 3 secs if an immediate takeoff is reqd
//cout << "Reducing response time to request due imminent traffic\n";
}
} else {
//cout << "Not next to take off - respond with hold\n";
}
//cout << "t = " << t << '\n';
@ -719,7 +1016,31 @@ void FGTower::ContactAtHoldShort(PlaneRec plane, FGAIPlane* requestee, tower_tra
void FGTower::RequestLandingClearance(string ID) {
//cout << "Request Landing Clearance called...\n";
// Assume this comes from the user - have another function taking a pointer to the AIplane for the AI traffic.
// For now we'll also assume that the user is a light plane and can get him/her to join the circuit if necessary.
TowerPlaneRec* t = new TowerPlaneRec;
t->isUser = true;
t->clearedToLand = false;
t->pos.setlon(user_lon_node->getDoubleValue());
t->pos.setlat(user_lat_node->getDoubleValue());
t->pos.setelev(user_elev_node->getDoubleValue());
// TODO
// Calculate where the user is in relation to the active runway and it's circuit
// and set the op-type as appropriate.
// HACK - to get up and running I'm going to assume that the user contacts tower on a staight-in final for now.
t->opType = STRAIGHT_IN;
t->plane.type = GA_SINGLE; // FIXME - Another assumption!
t->plane.callsign = ID;
appList.push_back(t); // Not necessarily permanent
AddToTrafficList(t);
}
void FGTower::RequestDepartureClearance(string ID) {
//cout << "Request Departure Clearance called...\n";
}

43
src/ATC/tower.hxx
View file

@ -50,7 +50,7 @@ enum tower_traffic_type {
TTT_UNKNOWN, // departure, but we don't know if for circuits or leaving properly
STRAIGHT_IN
// Umm - what's the difference between INBOUND and STRAIGHT_IN ?
};
}; // TODO - need some differentiation of IFR and VFR traffic in order to give the former priority.
// Structure for holding details of a plane under tower control.
// Not fixed yet - may include more stuff later.
@ -141,6 +141,15 @@ public:
bool GetCrosswindConstraint(double& cpos);
bool GetDownwindConstraint(double& dpos);
bool GetBaseConstraint(double& bpos);
// Returns true if OK to transmit on this frequency
inline bool FreqClear() { return freqClear; }
// Indicate that the frequency is in use
inline void FreqInUse() { freqClear = false; }
// The idea is that AI traffic or the user ATC dialog box calls FreqInUse() when they begin transmitting,
// and that the tower control sets freqClear back to true following a reply.
// AI traffic should check FreqClear() is true prior to transmitting.
// The user will just have to wait for a gap in dialog as in real life.
private:
FGATCMgr* ATCmgr;
@ -153,14 +162,23 @@ private:
// Figure out if a given position lies on a runway or not
bool OnAnyRunway(Point3D pt);
// Calculate the eta of each plane to the threshold.
// Calculate the eta of a plane to the threshold.
// For ground traffic this is the fastest they can get there.
// For air traffic this is the middle approximation.
void CalcETA(TowerPlaneRec* tpr);
// Iterate through all the lists and call CalcETA for all the planes.
void doThresholdETACalc();
// Order the list of traffic as per expected threshold use and flag any conflicts
bool doThresholdUseOrder();
// Calculate the crow-flys distance of a plane to the threshold in meters
double CalcDistOutM(TowerPlaneRec* tpr);
// Calculate the crow-flys distance of a plane to the threshold in miles
double CalcDistOutMiles(TowerPlaneRec* tpr);
void doCommunication();
void IssueLandingClearance(TowerPlaneRec* tpr);
@ -170,6 +188,8 @@ private:
bool display; // Flag to indicate whether we should be outputting to the ATC display.
bool displaying; // Flag to indicate whether we are outputting to the ATC display.
bool freqClear; // Flag to indicate if the frequency is clear of ongoing dialog
// environment - need to make sure we're getting the surface winds and not winds aloft.
SGPropertyNode* wind_from_hdg; //degrees
SGPropertyNode* wind_speed_knots; //knots
@ -189,12 +209,18 @@ private:
// or possibly another data structure with the positions of the inactive planes.
// Need a data structure to hold outstanding communications from aircraft.
// Linked-list of planes on approach ordered with nearest first (timewise).
// Linked-list of planes on approach to active rwy ordered with nearest first (timewise).
// Includes planes that have landed but not yet vacated runway.
// Somewhat analagous to the paper strips used (used to be used?) in real life.
// Doesn't include planes in circuit until they turn onto base/final?
// TODO - may need to alter this for operation to more than one active rwy.
tower_plane_rec_list_type appList;
tower_plane_rec_list_iterator appListItr;
// What should we do with planes approaching the airport to join the circuit somewhere
// but not on straight-in though? - put them in here for now.
tower_plane_rec_list_type circuitAppList;
tower_plane_rec_list_iterator circuitAppListItr;
// List of departed planes (planes doing circuits go into circuitList not depList after departure)
tower_plane_rec_list_type depList;
@ -215,6 +241,17 @@ private:
// List of all planes due to use a given rwy arranged in projected order of rwy use
tower_plane_rec_list_type trafficList; // TODO - needs to be expandable to more than one rwy
tower_plane_rec_list_iterator trafficListItr;
// Returns true if successful
bool RemoveFromTrafficList(string id);
// Return the ETA of plane no. list_pos (1-based) in the traffic list.
// i.e. list_pos = 1 implies next to use runway.
double GetTrafficETA(unsigned int list_pos);
// Add a tower plane rec with ETA to the traffic list in the correct position ETA-wise.
// Returns true if this could cause a threshold ETA conflict with other traffic, false otherwise.
bool AddToTrafficList(TowerPlaneRec* t, bool holding = false);
// Ground can be separate or handled by tower in real life.
// In the program we will always use a separate FGGround class, but we need to know