// SG_PI and SGD_PI (float and double) come from plib/sg.h
-// 2 * PI
+/** 2 * PI */
#define SGD_2PI 6.28318530717958647692
-// PI / 2
+/** PI / 2 */
#ifdef M_PI_2
# define SGD_PI_2 M_PI_2
#else
# define SGD_PI_2 1.57079632679489661923
#endif
-// PI / 4
+/** PI / 4 */
#define SGD_PI_4 0.78539816339744830961
-#ifndef M_E
-# define M_E 2.7182818284590452354
+/** \def SG_E "e" */
+#ifdef M_E
+# define SG_E M_E
+#else
+# define SG_E 2.7182818284590452354
#endif
-// SG_ONE_SECOND is pi/180/60/60, or about 100 feet at earths' equator
+/** pi/180/60/60, or about 100 feet at earths' equator */
#define SG_ONE_SECOND 4.848136811E-6
-// Radius of Earth in kilometers at the equator. Another source had
-// 6378.165 but this is probably close enough
+/** Radius of Earth in kilometers at the equator. Another source had
+ * 6378.165 but this is probably close enough */
#define SG_EARTH_RAD 6378.155
// Earth parameters for WGS 84, taken from LaRCsim/ls_constants.h
-// Value of earth radius from [8]
-#define EQUATORIAL_RADIUS_FT 20925650. // ft
-#define EQUATORIAL_RADIUS_M 6378138.12 // meter
-// Radius squared
-#define RESQ_FT 437882827922500. // ft
-#define RESQ_M 40680645877797.1344 // meter
-
-#if 0
-// Value of earth flattening parameter from ref [8]
-//
-// Note: FP = f
-// E = 1-f
-// EPS = sqrt(1-(1-f)^2)
-//
+/** Value of earth radius from LaRCsim (ft) */
+#define SG_EQUATORIAL_RADIUS_FT 20925650.
-#define FP 0.003352813178
-#define E 0.996647186
-#define EPS 0.081819221
-#define INVG 0.031080997
+/** Value of earth radius from LaRCsim (meter) */
+#define SG_EQUATORIAL_RADIUS_M 6378138.12
-// Time Related Parameters
+/** Radius squared (ft) */
+#define SG_EQ_RAD_SQUARE_FT 437882827922500.
-#define MJD0 2415020.0
-#define J2000 (2451545.0 - MJD0)
-#define SIDRATE .9972695677
-#endif
+/** Radius squared (meter) */
+#define SG_EQ_RAD_SQUARE_M 40680645877797.1344
// Conversions
-// Degrees to Radians
-#define DEG_TO_RAD 0.017453292 // deg*pi/180 = rad
-
-// Radians to Degrees
-#define RAD_TO_DEG 57.29577951 // rad*180/pi = deg
+/** Arc seconds to radians. (arcsec*pi)/(3600*180) = rad */
+#define SG_ARCSEC_TO_RAD 4.84813681109535993589e-06
-// Arc seconds to radians // (arcsec*pi)/(3600*180) = rad
-#define ARCSEC_TO_RAD 4.84813681109535993589e-06
+/** Radians to arc seconds. (rad*3600*180)/pi = arcsec */
+#define SG_RAD_TO_ARCSEC 206264.806247096355156
-// Radians to arc seconds // (rad*3600*180)/pi = arcsec
-#define RAD_TO_ARCSEC 206264.806247096355156
+/** Feet to Meters */
+#define SG_FEET_TO_METER 0.3048
-// Feet to Meters
-#define FEET_TO_METER 0.3048
+/** Meters to Feet */
+#define SG_METER_TO_FEET 3.28083989501312335958
-// Meters to Feet
-#define METER_TO_FEET 3.28083989501312335958
+/** Meters to Nautical Miles. 1 nm = 6076.11549 feet */
+#define SG_METER_TO_NM 0.00053995680
-// Meters to Nautical Miles, 1 nm = 6076.11549 feet
-#define METER_TO_NM 0.00053995680
+/** Nautical Miles to Meters */
+#define SG_NM_TO_METER 1852.0000
-// Nautical Miles to Meters
-#define NM_TO_METER 1852.0000
+/** Radians to Nautical Miles. 1 nm = 1/60 of a degree */
+#define SG_NM_TO_RAD 0.00029088820866572159
-// Radians to Nautical Miles, 1 nm = 1/60 of a degree
-#define NM_TO_RAD 0.00029088820866572159
+/** Nautical Miles to Radians */
+#define SG_RAD_TO_NM 3437.7467707849392526
-// Nautical Miles to Radians
-#define RAD_TO_NM 3437.7467707849392526
-
-// For divide by zero avoidance, this will be close enough to zero
+/** For divide by zero avoidance, this will be close enough to zero */
#define SG_EPSILON 0.0000001
-// Highest binobj format version we know how to read/write. This starts at
-// 0 and can go up to 65535
+/** Highest binobj format version we know how to read/write. This starts at
+ * 0 and can go up to 65535 */
#define SG_BINOBJ_VERSION 5
-// for backwards compatibility
+
+/** for backwards compatibility */
#define SG_SCENERY_FILE_FORMAT "0.4"