X-Git-Url: https://git.mxchange.org/?a=blobdiff_plain;f=simgear%2Fconstants.h;h=df0fc8baa3e2d74870ec68551b087322090633d5;hb=59df72c4b07bb7873f39f9a7b4ce1948c52e550a;hp=0ce5ab9e7866b26745ca10a832a654336f59fe0b;hpb=dcb95d131bc6aef1abe25d1f415e309f06e52436;p=simgear.git

diff --git a/simgear/constants.h b/simgear/constants.h
index 0ce5ab9e..df0fc8ba 100644
--- a/simgear/constants.h
+++ b/simgear/constants.h
@@ -31,14 +31,8 @@
 
 #include <simgear/compiler.h>
 
-#ifdef SG_HAVE_STD_INCLUDES
-#  include <cmath>
-#else
-#  ifdef SG_MATH_EXCEPTION_CLASH
-#    define exception C_exception
-#  endif
-#  include <math.h>
-#endif
+#include <cmath>
+
 
 #include <plib/sg.h>
 
@@ -75,6 +69,8 @@
  *  6378.165 but this is probably close enough */
 #define SG_EARTH_RAD 6378.155
 
+// Maximum terrain elevation from sea level
+#define SG_MAX_ELEVATION_M 9000.0
 
 // Earth parameters for WGS 84, taken from LaRCsim/ls_constants.h
 
@@ -128,6 +124,12 @@
 /** Knots to Miles per second */
 #define SG_KT_TO_MPS        0.5144444444444444444
 
+/** Feet per second to Knots */
+#define SG_FPS_TO_KT        0.5924838012958962841
+
+/** Knots to Feet per second */
+#define SG_KT_TO_FPS        1.6878098571011956874
+
 /** Miles per second to Miles per hour */
 #define SG_MPS_TO_MPH       2.2369362920544020312