From 49434e3085977698e2cb5879cc709f7148c914c7 Mon Sep 17 00:00:00 2001
From: daveluff <daveluff>
Date: Tue, 15 Apr 2003 10:37:58 +0000
Subject: [PATCH] Fixed some stuff in runway number to spoken string function,
 and added Alexander's function to get the minimum angular difference between
 two headings from approach to ATCutils

---
 src/ATC/ATCutils.cxx | 28 ++++++++++++++++++++++++++--
 src/ATC/ATCutils.hxx |  4 ++++
 2 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/src/ATC/ATCutils.cxx b/src/ATC/ATCutils.cxx
index 1c182357e..20a781902 100644
--- a/src/ATC/ATCutils.cxx
+++ b/src/ATC/ATCutils.cxx
@@ -80,7 +80,7 @@ string ConvertRwyNumToSpokenString(int n) {
 	return(str);
 }
 
-// Assumes we get a two-digit string optionally appended with R or L
+// Assumes we get a two-digit string optionally appended with L, R or C
 // eg 01 07L 29R 36
 // Anything else is not guaranteed to be handled correctly!
 string ConvertRwyNumToSpokenString(string s) {
@@ -88,7 +88,16 @@ string ConvertRwyNumToSpokenString(string s) {
 		return(ConvertRwyNumToSpokenString(atoi(s.c_str())));
 	} else {
 		string r = ConvertRwyNumToSpokenString(atoi(s.substr(0,2).c_str()));
-		return(r += (s.substr(2,1) == "L" ? " left" : " right"));	// Warning - not much error checking there!
+		if(s.substr(2,1) == "L") {
+			r += " left";
+		} else if(s.substr(2,1) == "R") {
+			r += " right";
+		} else if(s.substr(2,1) == "C") {
+			r += " center";
+		} else {
+			SG_LOG(SG_ATC, SG_WARN, "WARNING: Unknown suffix " << s.substr(2,1) << " from runway ID " << s << " in ConvertRwyNumToSpokenString(...)");
+		}
+		return(r);
 	}
 }
 	
@@ -128,6 +137,8 @@ string GetPhoneticIdent(int i) {
 	return("Error");
 }
 
+//================================================================================================================
+
 // Given two positions (lat & lon in degrees), get the HORIZONTAL separation (in meters)
 double dclGetHorizontalSeparation(Point3D pos1, Point3D pos2) {
 	double x;	//East-West separation
@@ -238,6 +249,19 @@ void dclBoundHeading(double &hdg) {
 	}
 }
 
+// smallest difference between two angles in degrees
+// difference is negative if a1 > a2 and positive if a2 > a1
+double GetAngleDiff_deg( const double &a1, const double &a2) {
+  
+  double a3 = a2 - a1;
+  while (a3 < 180.0) a3 += 360.0;
+  while (a3 > 180.0) a3 -= 360.0;
+
+  return a3;
+}
+
+//================================================================================================================
+
 // Airport stuff.  The next two functions are straight copies of their fg.... equivalents
 // in fg_init.cxx, and are just here temporarily until some rationalisation occurs.
 // find basic airport location info from airport database
diff --git a/src/ATC/ATCutils.hxx b/src/ATC/ATCutils.hxx
index b48739047..420b61632 100644
--- a/src/ATC/ATCutils.hxx
+++ b/src/ATC/ATCutils.hxx
@@ -77,6 +77,10 @@ double GetHeadingFromTo(Point3D A, Point3D B);
 // Given a heading (in degrees), bound it from 0 -> 360
 void dclBoundHeading(double &hdg);
 
+// smallest difference between two angles in degrees
+// difference is negative if a1 > a2 and positive if a2 > a1
+double GetAngleDiff_deg( const double &a1, const double &a2);
+
 
 /*******************************
 *
-- 
2.39.5