Add true and false global variables as aliases for boolean types to distinguish the use of "int" from "bool".

aerotow.nas

@@ -9,6 +9,16 @@
 # under the GNU Public License v3 (GPLv3)
 #
 
+#
+# Global aliases for boolean types to distinguish the use of "int" from "bool".
+# NOTE: unfortunately, it doesn't work as an assignment of a default value for a function parameter!
+#
+var true  = 1;
+var false = 0;
+
+#
+# Global object of Aerotow
+#
 var g_Aerotow = nil;
 
 #

gui/dialogs/towrope-configuration.xml

@@ -327,11 +327,11 @@
             <binding>
                 <command>nasal</command>
                 <script><![CDATA[
-                    setprop("/sim/hitches/aerotow/tow/length", 60.0);
+                    setprop("/sim/hitches/aerotow/tow/length", 60.0);              # hitch.nas 60.0
-                    setprop("/sim/hitches/aerotow/tow/brake-force", 100000.0);
+                    setprop("/sim/hitches/aerotow/tow/brake-force", 100000.0);     # hitch.nas 12345.0
-                    setprop("/sim/hitches/aerotow/tow/elastic-constant", 10000.0);
+                    setprop("/sim/hitches/aerotow/tow/elastic-constant", 10000.0); # hitch.nas 9111.0
-                    setprop("/sim/hitches/aerotow/rope/rope-diameter-mm", 20);
+                    setprop("/sim/hitches/aerotow/rope/rope-diameter-mm", 20);     # hitch.nas 20
-                    setprop("/sim/hitches/aerotow/tow/weight-per-m-kg-m", 1.0);
+                    setprop("/sim/hitches/aerotow/tow/weight-per-m-kg-m", 0.35);   # hitch.nas 0.35
                 ]]></script>
             </binding>
         </button>

nasal/aerotow.nas

@@ -55,7 +55,7 @@ var Aerotow = {
         me.message.success("Aerotow on the way");
 
         # Stop playing engine sound
-        setprop(me.addonNodePath ~ "/addon-devel/sound/enable", 0);
+        setprop(me.addonNodePath ~ "/addon-devel/sound/enable", false);
 
         # Wait a second for the engine sound to turn off
         Timer.new().singleShot(1, me, func () {
@@ -80,15 +80,15 @@ var Aerotow = {
     #
     # Main function to prepare AI scenario and run it.
     #
-    # Return 1 on successful, otherwise 0.
+    # Return true on successful, otherwise false.
     #
     startAerotow: func () {
         if (!me.scenario.unload()) {
-            return 0;
+            return false;
         }
 
         if (!me.scenario.generateXml()) {
-            return 0;
+            return false;
         }
 
         return me.scenario.load();
@@ -97,10 +97,10 @@ var Aerotow = {
     #
     # Function for unload our AI scenario.
     #
-    # Return 1 on successful, otherwise 0.
+    # Return true on successful, otherwise false.
     #
     stopAerotow: func () {
-        var withMessages = 1;
+        var withMessages = true;
         return me.scenario.unload(withMessages);
     },
 };

nasal/aircraft.nas

@@ -50,7 +50,7 @@ var Aircraft = {
     #
     # name - Name of aircraft to check.
     #
-    # Return 1 when match, otherwise 0.
+    # Return true when match, otherwise false.
     #
     isModelName: func (name) {
         return name == me.name or name == me.nameMenuCall;
@@ -69,8 +69,8 @@ var Aircraft = {
     # Return selected Aircraft object
     #
     # addon - Addon object
-    # isRouteMode - Use 1 to get the plane for the "Aerotow Route" dialog,
+    # isRouteMode - Use true to get the plane for the "Aerotow Route" dialog,
-    #               use 0 (default) for call the airplane for towing.
+    #               use false (default) for call the airplane for towing.
     #
     getSelected: func (addon, isRouteMode = 0) {
         var name = Aircraft.getSelectedAircraftName(addon, isRouteMode);
@@ -89,10 +89,10 @@ var Aircraft = {
     #
     #
     # addon - Addon object
-    # isRouteMode - Use 1 to get the plane for the "Aerotow Route" dialog,
+    # isRouteMode - Use true to get the plane for the "Aerotow Route" dialog,
-    #               use 0 (default) for call the airplane for towing.
+    #               use false (default) for call the airplane for towing.
     #
-    getSelectedAircraftName: func (addon, isRouteMode = 0) {
+    getSelectedAircraftName: func (addon, isRouteMode) {
         if (isRouteMode) {
             return getprop(addon.node.getPath() ~ "/addon-devel/route/ai-model") or g_Aircrafts[0].name;
         }

nasal/dialogs/route.nas

@@ -64,9 +64,9 @@ var RouteDialog = {
     calculateAltChangeAndTotals: func () {
         var totalDistance = 0.0;
         var totalAlt = 0.0;
-        var isEnd = 0;
+        var isEnd = false;
 
-        var isRouteMode = 1;
+        var isRouteMode = true;
         var aircraft = Aircraft.getSelected(me.addon, isRouteMode);
 
         for (var i = 0; i < me.maxRouteWaypoints; i += 1) {
@@ -84,7 +84,7 @@ var RouteDialog = {
                     totalAlt += altChange;
                 }
                 else {
-                    isEnd = 1;
+                    isEnd = true;
                 }
             }
         }

nasal/dialogs/thermal.nas

@@ -62,7 +62,7 @@ var Thermal = {
     #
     # Add thermal 300 m before glider position.
     #
-    # Return 1 on successful, otherwise 0.
+    # Return true on successful, otherwise false.
     #
     add: func () {
         var heading = getprop("/orientation/heading-deg") or 0;
@@ -87,10 +87,10 @@ var Thermal = {
 
         if (fgcommand("add-aiobject", args)) {
             me.message.success("The thermal has been added");
-            return 1;
+            return true;
         }
 
         me.message.error("Adding thermal failed");
-        return 0;
+        return false;
     },
 };

nasal/flight-plan.nas

@@ -124,17 +124,17 @@ var FlightPlan = {
     #
     # Initialize flight plan and set it to property tree
     #
-    # Return 1 on successful, otherwise 0.
+    # Return true on successful, otherwise false.
     #
     initial: func () {
         var location = me.getLocation();
         if (location == nil) {
-            return 0;
+            return false;
         }
 
         var aircraft = Aircraft.getSelected(me.addon);
 
-        var isGliderPos = 0;
+        var isGliderPos = false;
         me.initAircraftVariable(location, isGliderPos);
 
         # inittial readonly waypoint
@@ -189,28 +189,28 @@ var FlightPlan = {
 
         setprop(me.addonNodePath ~ "/addon-devel/route/wpts/description", "Default route around the start location");
 
-        return 1;
+        return true;
     },
 
     #
     # Generate the XML file with the flight plane for our plane for AI scenario.
-    # The file will be stored to $Fobj.HOME/Export/aerotown-addon-flightplan.xml.
+    # The file will be stored to $HOME/Export/Addons/org.flightgear.addons.Aerotow/AI/FlightPlans/aerotown-addon-flightplan.xml.
     #
-    # Return 1 on successful, otherwise 0.
+    # Return true on successful, otherwise false.
     #
     generateXml: func () {
         me.wptCount = 0;
 
         var location = me.getLocation();
         if (location == nil) {
-            return 0;
+            return false;
         }
 
         me.flightPlanWriter.open();
 
         var aircraft = Aircraft.getSelected(me.addon);
 
-        var isGliderPos = 1;
+        var isGliderPos = true;
         me.initAircraftVariable(location, isGliderPos);
 
         # Start at 2 o'clock from the glider...
@@ -218,7 +218,7 @@ var FlightPlan = {
         me.addWptGround({"hdgChange": 60, "dist": 25}, {"altChange": 0, "ktas": 5});
 
         # Reset coord and heading
-        isGliderPos = 0;
+        isGliderPos = false;
         me.initAircraftVariable(location, isGliderPos);
 
         var gliderOffsetM = me.getGliderOffsetFromRunwayThreshold(location);
@@ -268,7 +268,7 @@ var FlightPlan = {
 
         me.flightPlanWriter.close();
 
-        return 1;
+        return true;
     },
 
     #
@@ -286,9 +286,9 @@ var FlightPlan = {
     # Initialize AI aircraft variable
     #
     # location - Object of location from which the glider start.
-    # isGliderPos - Pass 1 for set AI aircraft's coordinates as glider position, 0 set coordinates as runway threshold.
+    # isGliderPos - Pass true for set AI aircraft's coordinates as glider position, false set coordinates as runway threshold.
     #
-    initAircraftVariable: func (location, isGliderPos = 1) {
+    initAircraftVariable: func (location, isGliderPos) {
         var gliderCoord = geo.aircraft_position();
 
         # Set coordinates as glider position or runway threshold
@@ -318,7 +318,7 @@ var FlightPlan = {
             return rwyThreshold.distance_to(gliderCoord);
         }
 
-        # We are not on the runway
+        # We are not on the runway, return 0 distance
         return 0;
     },
 

nasal/scenario.nas

@@ -38,7 +38,7 @@ var Scenario = {
         obj.listeners = [];
         obj.routeDialog = RouteDialog.new(addon, message);
         obj.flightPlan = FlightPlan.new(addon, message, obj.routeDialog);
-        obj.isScenarioLoaded = 0;
+        obj.isScenarioLoaded = false;
         obj.scenarioPath = addon.storagePath ~ "/" ~ Scenario.FILENAME_SCENARIO;
 
         obj.flightPlan.initial();
@@ -64,11 +64,13 @@ var Scenario = {
 
     #
     # Generate the XML file with the AI scenario.
-    # The file will be stored to $FG_HOME/Export/aerotown-addon.xml.
+    # The file will be stored to $FG_HOME/Export/Addons/org.flightgear.addons.Aerotow/aerotown-addon.xml.
+    #
+    # Return true on successful, otherwise false
     #
     generateXml: func () {
         if (!me.flightPlan.generateXml()) {
-            return 0;
+            return false;
         }
 
         var scenarioXml = {
@@ -82,7 +84,7 @@ var Scenario = {
                         "class":      "aerotow-dragger",
                         "model":      Aircraft.getSelected(me.addon).modelPath,
                         "flightplan": FlightPlan.FILENAME_FLIGHTPLAN,
-                        "repeat":     1,
+                        "repeat":     true, # start again indefinitely
                     }
                 }
             }
@@ -93,7 +95,7 @@ var Scenario = {
 
         me.addScenarioToPropertyList();
 
-        return 1;
+        return true;
     },
 
     #
@@ -114,67 +116,67 @@ var Scenario = {
     },
 
     #
-    # Return 1 if scenario is already added to "/sim/ai/scenarios" property list, otherwise return 0.
+    # Return true if scenario is already added to "/sim/ai/scenarios" property list, otherwise return false.
     #
     isAlreadyAdded: func () {
         foreach (var scenario; props.globals.getNode("/sim/ai/scenarios").getChildren("scenario")) {
             var id = scenario.getChild("id");
             if (id != nil and id.getValue() == Scenario.SCENARIO_ID) {
-                return 1;
+                return true;
             }
         }
 
-        return 0;
+        return false;
     },
 
     #
     # Load scenario
     #
-    # Return 1 on successful, otherwise 0.
+    # Return true on successful, otherwise false.
     #
     load: func () {
         var args = props.Node.new({ "name": Scenario.SCENARIO_ID });
         if (fgcommand("load-scenario", args)) {
-            me.isScenarioLoaded = 1;
+            me.isScenarioLoaded = true;
             me.message.success("Let's fly!");
 
             # Enable engine sound
-            setprop(me.addonNodePath ~ "/addon-devel/sound/enable", 1);
+            setprop(me.addonNodePath ~ "/addon-devel/sound/enable", true);
-            return 1;
+            return true;
         }
 
         me.message.error("Tow failed!");
-        return 0;
+        return false;
     },
 
     #
     # Unload scenario
     #
-    # withMessages - Set 1 to display messages.
+    # withMessages - Set true to display messages.
     #
-    # Return 1 on successful, otherwise 0.
+    # Return true on successful, otherwise false.
     #
     unload: func (withMessages = 0) {
         if (me.isScenarioLoaded) {
             var args = props.Node.new({ "name": Scenario.SCENARIO_ID });
             if (fgcommand("unload-scenario", args)) {
-                me.isScenarioLoaded = 0;
+                me.isScenarioLoaded = false;
 
                 if (withMessages) {
                     me.message.success("Aerotown disabled");
                 }
-                return 1;
+                return true;
             }
 
             if (withMessages) {
                 me.message.error("Aerotown disable failed");
             }
-            return 0;
+            return false;
         }
 
         if (withMessages) {
             me.message.success("Aerotown already disabled");
         }
-        return 1;
+        return true;
     },
 };

nasal/timer.nas

@@ -33,7 +33,7 @@ var Timer = {
         var timer = maketimer(delaySec, self, func () {
             callback();
         });
-        timer.singleShot = 1;
+        timer.singleShot = true;
         timer.start();
 
         return timer;