From b6b4b5fe77239c6f0e367b6b289f6b09bd9bfc1b Mon Sep 17 00:00:00 2001
From: stuart <stuart>
Date: Sat, 3 May 2008 19:46:47 +0000
Subject: [PATCH] Add additional runway selection so the runway in use doesn't
 change as you roll past mid-point. Also fix possible bug for north-south
 runways.

---
 gui/dialogs/chat-menu.xml | 165 +++++++++++++++++++++-----------------
 1 file changed, 92 insertions(+), 73 deletions(-)

diff --git a/gui/dialogs/chat-menu.xml b/gui/dialogs/chat-menu.xml
index c229af03f..9b66a5cc6 100644
--- a/gui/dialogs/chat-menu.xml
+++ b/gui/dialogs/chat-menu.xml
@@ -48,7 +48,7 @@
     </color>
   </text>
   <text>
-    <halign>left</halign>    
+    <halign>left</halign>
     <property>/sim/multiplay/chat-menu/entry[1]</property>
     <live>true</live>
     <color>
@@ -130,7 +130,7 @@
       <![CDATA[
       var text = "";
       var topNode = "/sim/multiplay/chat-menu/config";
-      
+
       setprop("/sim/multiplay/chat-menu/entry", "1");
       setprop("/sim/multiplay/chat-menu/entry[1]", "2");
       setprop("/sim/multiplay/chat-menu/entry[2]", "3");
@@ -141,18 +141,17 @@
       setprop("/sim/multiplay/chat-menu/entry[7]", "8");
       setprop("/sim/multiplay/chat-menu/entry[8]", "9");
       setprop("/sim/multiplay/chat-menu/entry[9]", "0");
-      
+
       # Get the conversation tree.
       var entryNodes = props.globals.getNode("/sim/multiplay/chat-menu").getChildren("entry");
       var pos = props.globals.getNode(topNode);
-      
+
       # Get various substitution values.
       var callsign = getprop("/sim/multiplay/callsign");
 
       # Simple rounding of altitude to 100 ft.
       var altitude = int(getprop("/position/altitude-ft")/100) * 100;
-    
-      
+
       var type = getprop("/sim/description");
       if (type != "")
       {
@@ -163,7 +162,7 @@
 
       # Get the nearest airport.
       var airport = airportinfo();
-      
+
       # Get the complement of each runway to create a full set.
       foreach (var rwy; keys(airport.runways)) {
         if (!string.isdigit(rwy[0]))
@@ -177,54 +176,74 @@
           width: r.width, heading: math.mod(r.heading + 180, 360),
           threshold1: r.threshold2,
         };
-      }      
-      
+      }
+
       # Determine the active runway. We have two ways to do this:
-      # - If the aircraft is on the ground (or very close to it), we'll try to determine 
-      # the runway it is closest to.
+      # - If the aircraft is on the ground (or very close to it), we'll try to determine
+      # the runway it is closest to, and facing the correct direction for.
       # - If the aircraft is in the air, we'll work out the active runway based on the wind.
-      
+
       var active_runway = "";
       var on_ground = (getprop("/position/altitude-agl-ft") < 100);
-      
+
       if (on_ground)
       {
-        # To find out the closest runway to the aircrafts position, we'll look at the heading 
-        # required to go from the aircraft's current position to the center of each runway. 
-        # The closer this is to the runways real heading, the more likely this is the runway 
-        # we're on. Note that we can't rely on /sim/atc/runway, as this is only set on 
+        # To find out the closest runway to the aircrafts position, we'll look at the heading
+        # required to go from the aircraft's current position to the center of each runway.
+        # The closer this is to the runways real heading, the more likely this is the runway
+        # we're on. Note that we can't rely on /sim/atc/runway, as this is only set on
         # initialization.
         var max = 360;
         var loc = geo.aircraft_position();
-        
+
         foreach (var r; keys(airport.runways)) {
           var curr = airport.runways[r];
           var p = geo.Coord.new();
           p.set_latlon(curr.lat, curr.lon, airport.elevation);
-          
-          var course = loc.course_to(p);
-          var deviation = math.abs(course - curr.heading);
-          
+
+          var course = loc.course_to(p) - curr.heading;
+          while (course >= 180) course -= 360;
+          while (course < -180) course += 360;
+
+          var deviation = math.abs(course);
+
           if (deviation < max)
           {
             active_runway = r;
             max = deviation;
           }
         }
+
+        # It may be the case that we're taxiing down the runway, past the mid-point.
+        # If the aircraft is facing the "wrong" way for this runway, then take the
+        # reciprocal runway.
+        var heading = getprop("/orientation/heading-magnetic-deg");
+        var deviation = heading - airport.runways[active_runway].heading;
+
+        while (deviation >= 180) deviation -= 360;
+        while (deviation < -180) deviation += 360;
+        deviation = math.abs(deviation);
+
+        if (deviation > 90)
+        {
+          var number = math.mod(num(substr(active_runway, 0, 2)) + 18, 36);
+          var side = substr(active_runway, 2, 1);
+          active_runway = sprintf("%02d%s", number, side == "R" ? "L" : side == "L" ? "R" : side);
+        }
       }
       else
-      {      
+      {
         var wind_speed = getprop("/environment/wind-speed-kt");
         var wind_from = wind_speed ? getprop("/environment/wind-from-heading-deg") : 270;
         var max = -1;
 
         foreach (var r; keys(airport.runways)) {
           var curr = airport.runways[r];
-        
+
           var wind = wind_from - curr.heading;
           while (wind >= 180) wind -= 360;
           while (wind < -180) wind += 360;
-        
+
           var deviation = math.abs(wind) + 1e-20;
           var v = (0.01 * curr.length + 0.01 * curr.width) / deviation;
 
@@ -232,23 +251,23 @@
             max = v;
             active_runway = r;
           }
-        }        
+        }
       }
-               
-      # Find our distance and cardinal direction to the airport.            
+
+      # Find our distance and cardinal direction to the airport.
       var directions = split(",", "North,North East,East,South East,South,South West,West,North West");
       var loc = geo.aircraft_position();
-      var airportloc = geo.Coord.new();      
+      var airportloc = geo.Coord.new();
       airportloc.set_latlon(airport.lat, airport.lon, airport.elevation);
-      
+
       # We want the course _from_ the airport to the aircraft - for reporting ".. approaching from the SW"
       var airport_course = airportloc.course_to(loc);
       var airport_distance = int((airportloc.distance_to(loc) / 1609) + 0.5);
-      
+
       # Get an index into our array of directions.
       var dir = int(math.mod((airport_course + 22.5), 360) / 45);
       var airport_direction = directions[dir];
-            
+
       # Now launch the keyboard listener.
       var kbdevent = setlistener("/devices/status/keyboard/event", func (event) {
 
@@ -257,58 +276,58 @@
           return;
 
         var key = event.getNode("key");
-        
+
         if (handle_key(key.getValue()))
           key.setValue(-1);           # drop key event
       });
-      
+
       var handle_key = func (key) {
         # We only handle keys 0-9 and Esc
-        
-        if (key == 27) 
+
+        if (key == 27)
         {
           # escape -> cancel
           removelistener(kbdevent);
           gui.popdown();
           fgcommand("dialog-close", props.Node.new({"dialog-name": "chat-menu"}));
           return 1;
-        } 
-        
+        }
+
         if ((key < `0`) or (key > `9`))
         {
           # pass the event back.
-          return 0;        
+          return 0;
         }
-        
+
         if (key == `0`)
         {
-          # Go back one level.          
+          # Go back one level.
           text = "";
-          
+
           if (pos.getName() != "config")
           {
             # Build up the chat string again.
             pos = pos.getParent();
             var p = pos;
-          
-            while ((p.getName() != "config") and 
+
+            while ((p.getName() != "config") and
                    (p.getChild("name").getValue() != nil))
             {
               var t = string.trim(p.getChild("name").getValue());
-              
-              # Entries that begin with "[" are silent.              
+
+              # Entries that begin with "[" are silent.
               if (t[0] != `[`)
-              {            
+              {
                 text =  t ~ " " ~ text;
               }
-              
+
               p = p.getParent();
-            }            
+            }
           }
-          
+
           updateDialog();
         }
-                
+
         if (key == `1`)
         {
           # Go to edit mode using the inline editor.
@@ -317,18 +336,18 @@
           multiplayer.compose_message(text);
           fgcommand("dialog-close", props.Node.new({"dialog-name": "chat-menu"}));
         }
-        
+
         if ((key > `1`) and (key <= `9`))
         {
           # Select the appropriate new node and update.
           # The index starts from position 2.
-          var i = key - `2`; 
-          
+          var i = key - `2`;
+
           if (i > (size(pos.getChildren("menu")) -1))
           {
             # Drop out if the user has entered a too large value.
             return 0;
-          }   
+          }
 
           var t = entryNodes[i].getValue();
 
@@ -351,16 +370,16 @@
             fgcommand("dialog-close", props.Node.new({"dialog-name": "chat-menu"}));
           }
           else
-          {          
+          {
             # We've got more tree to traverse.
             updateDialog();
           }
         }
-        
+
         # If we got here, we consumed the event
-        return 1;        
+        return 1;
       }
-      
+
       # Substitute simple values into the string.
       # The values we handle are
       #
@@ -373,47 +392,47 @@
       #
       var subvals = func (str) {
         var t = "";
-        
-        for (var p = 0; p < size(str); p += 1) 
+
+        for (var p = 0; p < size(str); p += 1)
         {
-          if (str[p] == `!`)    t ~= airport_direction;                      
-          elsif (str[p] == `^`) t ~= airport_distance;      
+          if (str[p] == `!`)    t ~= airport_direction;
+          elsif (str[p] == `^`) t ~= airport_distance;
           elsif (str[p] == `(`) t ~= active_runway;
-          elsif (str[p] == `*`) t ~= airport.name;          
+          elsif (str[p] == `*`) t ~= airport.name;
           elsif (str[p] == `%`) t ~= type;
           elsif (str[p] == `#`) t ~= callsign;
-          elsif (str[p] == `$`) t ~= altitude;          
+          elsif (str[p] == `$`) t ~= altitude;
           else t ~= chr(str[p]);
         }
-        
+
         return t;
       }
 
       var updateDialog = func {
-      
+
         var children = pos.getChildren("menu");
         var i = 0;
         foreach(var c; children)
         {
           var p = i + 2;
           var txt = p ~ ': ' ~ subvals(c.getChild("name").getValue());
-          
+
           if (i < 9)
-          {          
+          {
             entryNodes[i].setValue(txt);
           }
           i = i + 1;
         }
-        
+
         # Set the rest of the dialog to blank.
         while (i <= 9)
-        {          
+        {
           entryNodes[i].setValue("");
           i = i + 1;
         }
-        
+
         # Write the popup.
-        gui.popupTip(text, 1000000);                
+        gui.popupTip(text, 1000000);
       }
 
       # Start by updating the dialog.