From 255d521f0a26360d27f381cc8184c0152bc9fa31 Mon Sep 17 00:00:00 2001
From: oliskoli <oliskoli>
Date: Sat, 14 Apr 2007 15:25:20 +0000
Subject: [PATCH] Use global defined index of datum WGS84 and OSGB36.

---
 compegps.c   |  9 ++-------
 defs.h       |  2 ++
 dmtlog.c     | 13 +++++--------
 garmin_txt.c |  2 +-
 4 files changed, 10 insertions(+), 16 deletions(-)

diff --git a/compegps.c b/compegps.c
index 3156c55bd..b65b6912b 100644
--- a/compegps.c
+++ b/compegps.c
@@ -106,16 +106,11 @@ static
 void fix_datum(double *lat, double *lon)
 {
 	double amt;
-	static int wgs84;
-
-	if (wgs84 == 0) {
-		wgs84 = GPS_Lookup_Datum_Index("WGS 84");
-	}
 
 	/*
 	 * Avoid FP jitter in the common case.
  	 */
-	if (input_datum != wgs84) {
+	if (input_datum != DATUM_WGS84) {
 		GPS_Math_Known_Datum_To_WGS84_M(*lat, *lon, 0.0, lat, lon, 
 			&amt, input_datum);
 	}
@@ -341,7 +336,7 @@ static void
 compegps_rd_init(const char *fname)
 {
 	fin = gbfopen(fname, "rb", MYNAME);
-	input_datum = GPS_Lookup_Datum_Index("WGS 84");
+	input_datum = DATUM_WGS84;
 }
 
 static void
diff --git a/defs.h b/defs.h
index 43d30bd95..c0c68e56d 100644
--- a/defs.h
+++ b/defs.h
@@ -861,6 +861,8 @@ typedef enum {
 
 #define GRID_INDEX_MIN	grid_lat_lon_ddd
 #define GRID_INDEX_MAX	grid_utm
+
+#define DATUM_OSGB36	86
 #define DATUM_WGS84	118
 
 int parse_coordinates(const char *str, int datum, const grid_type grid,
diff --git a/dmtlog.c b/dmtlog.c
index 785ab0050..9a88c50aa 100644
--- a/dmtlog.c
+++ b/dmtlog.c
@@ -38,7 +38,7 @@ static char *xmlbin;
 static waypoint *xmlwpt;
 static route_head *xmltrk;
 static char *xmlgrid;
-static int xmldatum, datum_WGS84, datum_OSGB36;
+static int xmldatum;
 static double xmlEasting, xmlNorthing;
 static double xmlLatitude, xmlLongitude;
 static double xmlAltitude;
@@ -105,7 +105,7 @@ static xg_tag_mapping tlog3b_xgcb_map[] = {
 static void
 convert_datum(waypoint *wpt, int datum)
 {
-	if (datum != datum_WGS84) {
+	if (datum != DATUM_WGS84) {
 		double lat = wpt->latitude;
 		double lon = wpt->longitude;
 		double alt = wpt->altitude;
@@ -122,7 +122,7 @@ finalize_pt(waypoint *wpt)
 	if (strcmp(xmlgrid, "BNG") == 0) {
 		GPS_Math_NGENToAiry1830LatLon(xmlEasting, xmlNorthing, 
 		&wpt->latitude, &wpt->longitude);
-		xmldatum = datum_OSGB36;
+		xmldatum = DATUM_OSGB36;
 	}
 	else {
 		wpt->latitude = xmlLatitude;
@@ -219,7 +219,7 @@ static void
 tlog3b_xgcb_wptst(const char *args, const char **unused)
 {
 	xmlwpt = waypt_new();
-	xmldatum = datum_WGS84;
+	xmldatum = DATUM_WGS84;
 }
 
 
@@ -227,7 +227,7 @@ static void
 tlog3b_xgcb_tptst(const char *args, const char **unused)
 {
 	xmlwpt = waypt_new();
-	xmldatum = datum_WGS84;
+	xmldatum = DATUM_WGS84;
 }
 
 
@@ -551,9 +551,6 @@ dmtlog_rd_init(const char *fname)
 {
 	fin = gbfopen_le(fname, "rb", MYNAME);
 	
-	datum_OSGB36 = GPS_Lookup_Datum_Index("OSGB36");
-	datum_WGS84 = GPS_Lookup_Datum_Index("WGS84");
-	
 	xmlbin = NULL;
 	xmltrk = NULL;
 	xmlwpt = NULL;
diff --git a/garmin_txt.c b/garmin_txt.c
index bb8444f02..3638510d3 100644
--- a/garmin_txt.c
+++ b/garmin_txt.c
@@ -765,7 +765,7 @@ garmin_txt_wr_init(const char *fname)
 	
 	switch(grid_index) {
 	case grid_bng: /* force datum to "Ord Srvy Grt Britn" */
-		datum_index = gt_lookup_datum_index("OSGB36", MYNAME);
+		datum_index = DATUM_OSGB36;
 		break;
 	default:
 		datum_index = gt_lookup_datum_index(datum_str, MYNAME);
-- 
2.30.2