Make geoid separation availble to the Garmin.

3 files changed, 10 insertions, 1 deletions

diff --git a/garmin.c b/garmin.c
index 0124fe20..35bfd482 100644
--- a/garmin.c
+++ b/garmin.c
@@ -334,6 +334,10 @@ static int PrintPacket(struct gps_device_t *session, Packet_t *pkt)
 			, session->gpsdata.status);
 
 	    gpsd_report(3, "UTC Time: %lf\n", session->gpsdata.fix.time);
+	    gpsd_report(3, "Geoid: from garmin %lf, calculated %lf\n"
+		, pvt->msl_hght
+		, wgs84_separation(session->gpsdata.fix.latitude
+			, session->gpsdata.fix.longitude));
 	    gpsd_report(3, "Alt: %.3f, Epe: %.3f, Eph: %.3f, Epv: %.3f, Fix: %d, Gps_tow: %f, Lat: %.3f, Lon: %.3f, LonVel: %.3f, LatVel: %.3f, AltVel: %.3f, MslHgt: %.3f, Leap: %d, GarminDays: %ld\n"
 			, pvt->alt
 			, pvt->epe
diff --git a/geoid.c b/geoid.c
index 74599dd4..55d6901b 100644
--- a/geoid.c
+++ b/geoid.c
@@ -21,7 +21,9 @@ static double bilinear(double x1, double y1, double x2, double y2, double x, dou
  return (z22*(y-y1)*(x-x1)+z12*(y2-y)*(x-x1)+z21*(y-y1)*(x2-x)+z11*(y2-y)*(x2-x))/delta;
 }
 
-static double wgs84_separation(double lat, double lon)
+
+/* return wgs84 to MSL geoid separtion in meters, given a lat/lot */
+double wgs84_separation(double lat, double lon)
 {
 #define GEOID_ROW	19
 #define GEOID_COL	37
diff --git a/gpsutils.h b/gpsutils.h
index f6ef23c0..b396d115 100644
--- a/gpsutils.h
+++ b/gpsutils.h
@@ -6,3 +6,6 @@ extern double iso8601_to_unix(char *);
 extern char *unix_to_iso8601(double t, char *);
 extern double gpstime_to_unix(int, double, int);
 extern double earth_distance(double, double, double, double);
+
+/* return wgs84 to MSL geoid separtion in meters, given a lat/lot */
+extern double wgs84_separation(double lat, double lon);