Add more realistic aerodynamic effects for helicopters

src/obj.h

@@ -961,6 +961,9 @@ typedef struct {
 	 */
 	float		center_to_ground_height;
 
+	/* Rate of heading change due to torque (radians/cycle) */
+	float torque_velocity;
+
 
 	/* Moveable parts */
 	sar_obj_part_struct	**part;

src/sfm.h

@@ -42,6 +42,18 @@
  */
 #define SFMDefaultGravity	9.80665
 
+
+/*
+ *	Effective transactional lift speed value in m/s.
+ */
+#define SFMETLSpeed 12.35  // 24 knots
+
+/*
+ *	Transverse Flow Effect (TF) values in m/s.
+ */
+#define SFMTFStart 2.57 // 5 knots
+#define SFMTFEnd 12.86  // 25 knots
+
 /*
  *	Core structure:
  */
@@ -61,7 +73,11 @@ typedef struct {
 	SFMPositionStruct       actual_wind_vector;	/* In meters per Cycle */    
 	unsigned long		wind_flags;
 	SFMBoolean		wind_enabled;
-	/* Callbacks, typical inputs are; realm pointer,
+
+	/* Realism setting */
+	SFMFlightPhysicsLevel	flight_physics_level;
+
+        /* Callbacks, typical inputs are; realm pointer,
 	 * model pointer, client data
 	 */
 

src/sfmmodel.c

@@ -297,6 +297,10 @@ SFMBoolean SFMModelChangeValues(
 	{
 	    model->wingspan = value->wingspan;
 	}
+	if(flags & SFMFlagRotorDiameter)
+	{
+	    model->rotor_diameter = value->rotor_diameter;
+	}
 	if(flags & SFMFlagGearState)
 	{
 	    model->gear_state = value->gear_state;

src/sfmmodel.h

@@ -78,6 +78,8 @@
 #define SFMFlagStopped			((SFMFlags)1 << 41)
 #define SFMFlagLength			((SFMFlags)1 << 42)
 #define SFMFlagWingspan			((SFMFlags)1 << 43)
+#define SFMFlagRotorDiameter		((SFMFlags)1 << 44)
+#define SFMFlagSingleMainRotor		((SFMFlags)1 << 45)
 
 /*
  *	Flight model types:
@@ -148,6 +150,7 @@ typedef struct {
 	double			service_ceiling;	/* Meters. */
 	double			length;		/* Meters */
 	double			wingspan;	/* Meters */
+	double			rotor_diameter;	/* Meters */
 	double			belly_height;	/* Undercarrage to center, meters. */
 	SFMBoolean		gear_state;	/* True when down. */
 	int			gear_type;	/* One of SFMGearType*. */
@@ -165,6 +168,7 @@ typedef struct {
 								 * ground height,
 								 * in meters.
 								 */
+	double			torque_velocity;	/* Radians/cycle internal */
 	double			heading_control_coeff;	/* -1.0 to 1.0. */
 	double			pitch_control_coeff;	/* -1.0 to 1.0. */
 	double			bank_control_coeff;	/* -1.0 to 1.0. */