X-Git-Url: https://git.street.me.uk/andy/viking.git/blobdiff_plain/9ac936f269ba5b2a62798014f2054eb6462a05af..ab1e06931aa45edfe302f6a9cab91773b2444d4d:/src/globals.h?ds=sidebyside

diff --git a/src/globals.h b/src/globals.h
index 8e0aa0b1..fb4d6f90 100644
--- a/src/globals.h
+++ b/src/globals.h
@@ -34,6 +34,22 @@
 
 #define VIK_FEET_IN_METER 3.2808399
 #define VIK_METERS_TO_FEET(X) ((X)*VIK_FEET_IN_METER)
+#define VIK_FEET_TO_METERS(X) (X/VIK_FEET_IN_METER)
+
+/* MPS - Metres Per Second */
+/* MPH - Metres Per Hour */
+#define VIK_MPH_IN_MPS 2.23693629
+#define VIK_MPS_TO_MPH(X) (X*VIK_MPH_IN_MPS)
+#define VIK_MPH_TO_MPS(X) (X/VIK_MPH_IN_MPS)
+
+/* KPH - Kilometres Per Hour */
+#define VIK_KPH_IN_MPS 3.6
+#define VIK_MPS_TO_KPH(X) (X*VIK_KPH_IN_MPS)
+#define VIK_KPH_TO_MPS(X) (X/VIK_KPH_IN_MPS)
+
+#define VIK_KNOTS_IN_MPS 1.94384449
+#define VIK_MPS_TO_KNOTS(X) (X*VIK_KNOTS_IN_MPS)
+#define VIK_KNOTS_TO_MPS(X) (X/VIK_KNOTS_IN_MPS)
 
 #define VIK_DEFAULT_ALTITUDE 0.0
 #define VIK_DEFAULT_DOP 0.0