X-Git-Url: https://git.street.me.uk/andy/viking.git/blobdiff_plain/6c20e59a815984bf502aa9d1af8bd93d33727f87..0eb26799f0090b0a294cf0a61d17ba94b8d19132:/src/globals.h

diff --git a/src/globals.h b/src/globals.h
index 8d8258fa..40d58d58 100644
--- a/src/globals.h
+++ b/src/globals.h
@@ -33,7 +33,27 @@
 #define MPP_TO_ALTI 0.7134044
 
 #define VIK_FEET_IN_METER 3.2808399
-#define VIK_METERS_TO_FEET(X) (X*VIK_FEET_IN_METER)
+#define VIK_METERS_TO_FEET(X) ((X)*VIK_FEET_IN_METER)
+#define VIK_FEET_TO_METERS(X) ((X)/VIK_FEET_IN_METER)
+
+#define VIK_MILES_IN_METER 0.000621371192
+#define VIK_METERS_TO_MILES(X) ((X)*VIK_MILES_IN_METER)
+#define VIK_MILES_TO_METERS(X) ((X)/VIK_MILES_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