Redesign of the latitude and longitude formatting for the HUD.

This follows from http://thread.gmane.org/gmane.games.flightgear.devel/78650 and
resolves the sign bug https://sourceforge.net/p/flightgear/codetickets/1778/ .

Combined with a matching change to FGData, this changes the HUD formats from the
current set of 3 (note that the text in brackets is not shown in the HUD
preferences PUI dialog, but is show here for reference):

    0) Decimal degrees (37.618890N -122.375000W)
    1) Degrees, minutes (37*37.133N -122*22.500W)
    2) Degrees, minutes, seconds (37*37 08.0 N -122*22 30.0 W)

to (here the text in brackets will be shown in the PUI dialog):

    0) DDD format (37.618890N 122.375000W)
    1) DMM format (37*37.133'N 122*22.500'W)
    2) DMS format (37*37'08.0"N 122*22'30.0"W)
    3) Signed DDD format (37.618890 -122.375000)
    4) Signed DMM format (37*37.133' -122*22.500')
    5) Signed DMS format (37*37'08.0" -122*22'30.0")
    6) Zero padded DDD (51.477500N 000.461389W)
    7) Zero padded DMM (51*28.650'N 000*27.683'W)
    8) Zero padded DMS (51*28'39.0"N 000*27'41.0"W)
    9) Trinity House Navigation (51* 28'.650N 000* 27'.683W)

diff --git a/src/Main/fg_props.cxx b/src/Main/fg_props.cxx
index 43b3228cb4cb08a1566d5adaeaf68b0e24bd0118..f348bc3bd02b1e02e250b6fbb7d913d22b67deaa 100644 (file)
--- a/src/Main/fg_props.cxx
+++ b/src/Main/fg_props.cxx
@@ -366,85 +366,160 @@ SGConstPropertyNode_ptr FGProperties::_longDeg;
 SGConstPropertyNode_ptr FGProperties::_latDeg;
 SGConstPropertyNode_ptr FGProperties::_lonLatformat;
 
-const char *
-FGProperties::getLongitudeString ()
-{
-  static char buf[32];
-  double d = _longDeg->getDoubleValue();
-  int format = _lonLatformat->getIntValue();
-  char c = d < 0.0 ? 'W' : 'E';
-  d = fabs(d);
+/*
+ * Format the latitude and longitude floats into a character array using a variety of coordinate formats.
+ */
+static void
+formatLatLongString (double deg, int format, char *buf, char c) {
+  double min, sec;
+  int sign = deg < 0.0 ? -1 : 1;
+  deg = fabs(deg);
 
   if (format == 0) {
-    snprintf(buf, 32, "%3.6f%c", d, c);
+    // d.dddddd' (DDD format).
+    snprintf(buf, 32, "%3.6f%c", deg, c);
 
   } else if (format == 1) {
-    // dd mm.mmm' (DMM-Format) -- uses a round-off factor tailored to the
+    // d mm.mmm' (DMM format) -- uses a round-off factor tailored to the
     // required precision of the minutes field (three decimal places),
     // preventing minute values of 60.
-    double min = (d - int(d)) * 60.0;
+    min = (deg - int(deg)) * 60.0;
     if (min >= 59.9995) {
         min -= 60.0;
-        d += 1.0;
+        deg += 1.0;
     }
-    snprintf(buf, 32, "%d*%06.3f%c", int(d), fabs(min), c);
+    snprintf(buf, 32, "%d*%06.3f'%c", int(deg), fabs(min), c);
 
-  } else {
-    // mm'ss.s'' (DMS-Format) -- uses a round-off factor tailored to the
+  } else if (format == 2) {
+    // d mm'ss.s" (DMS format) -- uses a round-off factor tailored to the
     // required precision of the seconds field (one decimal place),
     // preventing second values of 60.
-    double min = (d - int(d)) * 60.0;
-    double sec = (min - int(min)) * 60.0;
+    min = (deg - int(deg)) * 60.0;
+    sec = (min - int(min)) * 60.0;
     if (sec >= 59.95) {
         sec -= 60.0;
         min += 1.0;
         if (min >= 60.0) {
             min -= 60.0;
-            d += 1.0;
+            deg += 1.0;
         }
     }
-    snprintf(buf, 32, "%d*%02d %04.1f%c", int(d),
-        int(min), fabs(sec), c);
-  }
-  buf[31] = '\0';
-  return buf;
-}
+    snprintf(buf, 32, "%d*%02d'%04.1f\"%c", int(deg), int(min), fabs(sec), c);
 
-const char *
-FGProperties::getLatitudeString ()
-{
-  static char buf[32];
-  double d = _latDeg->getDoubleValue();
-  int format = _lonLatformat->getIntValue();
-  char c = d < 0.0 ? 'S' : 'N';
-  d = fabs(d);
+  } else if (format == 3) {
+    // d.dddddd' (signed DDD format).
+    snprintf(buf, 32, "%3.6f", sign*deg);
 
-  if (format == 0) {
-    snprintf(buf, 32, "%3.6f%c", d, c);
+  } else if (format == 4) {
+    // d mm.mmm' (signed DMM format).
+    min = (deg - int(deg)) * 60.0;
+    if (min >= 59.9995) {
+        min -= 60.0;
+        deg += 1.0;
+    }
+    if (sign == 1) {
+        snprintf(buf, 32, "%d*%06.3f'", int(deg), fabs(min));
+    } else {
+        snprintf(buf, 32, "-%d*%06.3f'", int(deg), fabs(min));
+    }
 
-  } else if (format == 1) {
-    double min = (d - int(d)) * 60.0;
+  } else if (format == 5) {
+    // d mm'ss.s" (signed DMS format).
+    min = (deg - int(deg)) * 60.0;
+    sec = (min - int(min)) * 60.0;
+    if (sec >= 59.95) {
+        sec -= 60.0;
+        min += 1.0;
+        if (min >= 60.0) {
+            min -= 60.0;
+            deg += 1.0;
+        }
+    }
+    if (sign == 1) {
+        snprintf(buf, 32, "%d*%02d'%04.1f\"", int(deg), int(min), fabs(sec));
+    } else {
+        snprintf(buf, 32, "-%d*%02d'%04.1f\"", int(deg), int(min), fabs(sec));
+    }
+
+  } else if (format == 6) {
+    // dd.dddddd X, ddd.dddddd X (zero padded DDD format).
+    if (c == 'N' || c == 'S') {
+      snprintf(buf, 32, "%09.6f%c", deg, c);
+    } else {
+      snprintf(buf, 32, "%010.6f%c", deg, c);
+    }
+
+  } else if (format == 7) {
+    // dd mm.mmm' X, ddd mm.mmm' X (zero padded DMM format).
+    min = (deg - int(deg)) * 60.0;
     if (min >= 59.9995) {
         min -= 60.0;
-        d += 1.0;
+        deg += 1.0;
+    }
+    if (c == 'N' || c == 'S') {
+      snprintf(buf, 32, "%02d*%06.3f'%c", int(deg), fabs(min), c);
+    } else {
+      snprintf(buf, 32, "%03d*%06.3f'%c", int(deg), fabs(min), c);
     }
-    snprintf(buf, 32, "%d*%06.3f%c", int(d), fabs(min), c);
 
-  } else {
-    double min = (d - int(d)) * 60.0;
-    double sec = (min - int(min)) * 60.0;
+  } else if (format == 8) {
+    // dd mm'ss.s" X, dd mm'ss.s" X (zero padded DMS format).
+    min = (deg - int(deg)) * 60.0;
+    sec = (min - int(min)) * 60.0;
     if (sec >= 59.95) {
         sec -= 60.0;
         min += 1.0;
         if (min >= 60.0) {
             min -= 60.0;
-            d += 1.0;
+            deg += 1.0;
         }
     }
-    snprintf(buf, 32, "%d*%02d %04.1f%c", int(d),
-        int(min), fabs(sec), c);
+    if (c == 'N' || c == 'S') {
+      snprintf(buf, 32, "%02d*%02d'%04.1f\"%c", int(deg), int(min), fabs(sec), c);
+    } else {
+      snprintf(buf, 32, "%03d*%02d'%04.1f\"%c", int(deg), int(min), fabs(sec), c);
+    }
+
+  } else if (format == 9) {
+    // dd* mm'.mmm X, ddd* mm'.mmm X (Trinity House Navigation standard).
+    min = (deg - int(deg)) * 60.0;
+    if (min >= 59.9995) {
+        min -= 60.0;
+        deg += 1.0;
+    }
+    if (c == 'N' || c == 'S') {
+        snprintf(buf, 32, "%02d* %02d'.%03d%c", int(deg), int(min), int(round((min-int(min))*1000)), c);
+    } else {
+        snprintf(buf, 32, "%03d* %02d'.%03d%c", int(deg), int(min), int(round((min-int(min))*1000)), c);
+    }
+
+  } else {
+    // Empty the buffer for all invalid formats.
+    buf[0] = '\0';
   }
-  buf[31] = '\0';
+}
+
+const char *
+FGProperties::getLongitudeString ()
+{
+  static char buf[32];
+  double d = _longDeg->getDoubleValue();
+  int format = _lonLatformat->getIntValue();
+
+  char c = d < 0.0 ? 'W' : 'E';
+  formatLatLongString(d, format, buf, c);
+  return buf;
+}
+
+const char *
+FGProperties::getLatitudeString ()
+{
+  static char buf[32];
+  double d = _latDeg->getDoubleValue();
+  int format = _lonLatformat->getIntValue();
+
+  char c = d < 0.0 ? 'S' : 'N';
+  formatLatLongString(d, format, buf, c);
   return buf;
 }