Added some null pointer checks in FGAILocalTraffic to handle airports without tower

diff --git a/src/ATCDCL/AILocalTraffic.cxx b/src/ATCDCL/AILocalTraffic.cxx
index 2acf7d10dd612f9c027b3be771431d8ca50fc794..6c1b77d8f5da776381435328fe7c13074fdfcacc 100644 (file)
--- a/src/ATCDCL/AILocalTraffic.cxx
+++ b/src/ATCDCL/AILocalTraffic.cxx
@@ -841,7 +841,7 @@ void FGAILocalTraffic::FlyTrafficPattern(double dt) {
                // TODO - At hot 'n high airports this may be 500ft AGL though - need to make this a variable.
                if((_pos.getElevationM() - rwy.threshold_pos.getElevationM()) * SG_METER_TO_FEET > 700) {
                        double cc = 0.0;
-                       if(tower->GetCrosswindConstraint(cc)) {
+                       if(tower && tower->GetCrosswindConstraint(cc)) {
                                if(orthopos.y() > cc) {
                                        //cout << "Turning to crosswind, distance from threshold = " << orthopos.y() << '\n'; 
                                        leg = TURN1;
@@ -884,7 +884,7 @@ void FGAILocalTraffic::FlyTrafficPattern(double dt) {
                // turn 1000m out for now, taking other traffic into accout
                if(fabs(orthopos.x()) > 900) {
                        double dd = 0.0;
-                       if(tower->GetDownwindConstraint(dd)) {
+                       if(tower && tower->GetDownwindConstraint(dd)) {
                                if(fabs(orthopos.x()) > fabs(dd)) {
                                        //cout << "Turning to downwind, distance from centerline = " << fabs(orthopos.x()) << '\n'; 
                                        leg = TURN2;
@@ -930,7 +930,7 @@ void FGAILocalTraffic::FlyTrafficPattern(double dt) {
                        // For now we're assuming that we aim to follow the same glidepath regardless of wind.
                        double d1;
                        double d2;
-                       CalculateSoD((tower->GetBaseConstraint(d1) ? d1 : -1000.0), (tower->GetDownwindConstraint(d2) ? d2 : 1000.0 * patternDirection), (patternDirection ? true : false));
+                       CalculateSoD(((tower && tower->GetBaseConstraint(d1)) ? d1 : -1000.0), ((tower && tower->GetDownwindConstraint(d2)) ? d2 : 1000.0 * patternDirection), (patternDirection ? true : false));
                        if(SoD.leg == DOWNWIND) {
                                descending = (orthopos.y() < SoD.y ? true : false);
                        }
@@ -950,7 +950,7 @@ void FGAILocalTraffic::FlyTrafficPattern(double dt) {
                if(orthopos.y() < -1000.0 + turn_radius) {
                //if(orthopos.y() < -980) {
                        double bb = 0.0;
-                       if(tower->GetBaseConstraint(bb)) {
+                       if(tower && tower->GetBaseConstraint(bb)) {
                                if(fabs(orthopos.y()) > fabs(bb)) {
                                        //cout << "Turning to base, distance from threshold = " << fabs(orthopos.y()) << '\n'; 
                                        leg = TURN3;
@@ -982,7 +982,7 @@ void FGAILocalTraffic::FlyTrafficPattern(double dt) {
                        double d1;
                        // Make downwind leg position artifically large to avoid any chance of SoD being returned as
                        // on downwind when we are already on base.
-                       CalculateSoD((tower->GetBaseConstraint(d1) ? d1 : -1000.0), (10000.0 * patternDirection), (patternDirection ? true : false));
+                       CalculateSoD(((tower && tower->GetBaseConstraint(d1)) ? d1 : -1000.0), (10000.0 * patternDirection), (patternDirection ? true : false));
                        if(SoD.leg == BASE) {
                                descending = (fabs(orthopos.y()) < fabs(SoD.y) ? true : false);
                        }
@@ -1207,10 +1207,11 @@ void FGAILocalTraffic::CalculateSoD(double base_leg_pos, double downwind_leg_pos
 
 void FGAILocalTraffic::TransmitPatternPositionReport(void) {
        // airport name + "traffic" + airplane callsign + pattern direction + pattern leg + rwy + ?
-       string trns = "";
+       string trns;
        int code = 0;
-       
-       trns += tower->get_name();
+       const string& apt_name = tower ? tower->get_name() : airportID;
+
+       trns += apt_name;
        trns += " Traffic ";
        trns += plane.callsign;
        if(patternDirection == 1) {
@@ -1249,10 +1250,10 @@ void FGAILocalTraffic::TransmitPatternPositionReport(void) {
        }
        trns += ConvertRwyNumToSpokenString(rwy.rwyID);
        
-       trns += " ";
+       trns += ' ';
        
        // And add the airport name again
-       trns += tower->get_name();
+       trns += apt_name;
        
        pending_transmission = trns;
        ConditionalTransmit(60.0, code);                // Assume a report of this leg will be invalid if we can't transmit within a minute.