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- use SGGeodesy

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- fade out strong lift when disabled
- some tiny optimizations
This commit is contained in:
torsten 2009-06-10 19:52:39 +00:00 committed by Tim Moore
parent a29e5ce666
commit 93cc7e0e5b
2 changed files with 38 additions and 53 deletions
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78
src/Environment/ridge_lift.cxx
View file

@ -57,15 +57,17 @@ static inline double sign(double x) {
static const double BOUNDARY1_m = 40.0;
const double FGRidgeLift::dist_probe_m[] = { // in meters
0.0,
250.0,
750.0,
2000.0,
-100.0
};
//constructor
FGRidgeLift::FGRidgeLift ()
{
dist_probe_m[0] = 0.0; // in meters
dist_probe_m[1] = 250.0;
dist_probe_m[2] = 750.0;
dist_probe_m[3] = 2000.0;
dist_probe_m[4] = -100.0;
strength = 0.0;
timer = 0.0;
for( int i = 0; i < 5; i++ )
@ -92,11 +94,10 @@ void FGRidgeLift::init(void)
_surface_wind_speed_node =
fgGetNode("/environment/config/boundary/entry[0]/wind-speed-kt"
, true);
_earth_radius_node = fgGetNode("/position/sea-level-radius-ft", true);
_user_longitude_node = fgGetNode("/position/longitude-deg", true);
_user_latitude_node = fgGetNode("/position/latitude-deg", true);
_user_altitude_ft_node = fgGetNode("/position/altitude-ft", true);
_user_altitude_agl_ft_node = fgGetNode("/position/altitude-agl-ft", true);
_ground_elev_node = fgGetNode("/position/ground-elev-ft", true );
}
void FGRidgeLift::bind() {
@ -142,60 +143,48 @@ void FGRidgeLift::unbind() {
void FGRidgeLift::update(double dt) {
if( dt <= 0 ) // paused, do nothing but keep current lift
if( dt <= SGLimitsd::min() ) // paused, do nothing but keep current lift
return;
if( _enabled_node && false == _enabled_node->getBoolValue() ) {
// do nothing if lift has been zeroed
if( strength != 0.0 ) {
if( strength > 0.1 ) {
// slowly fade out strong lifts
strength = fgGetLowPass( strength, 0, dt );
} else {
strength = 0.0;
_ridge_lift_fps_node->setDoubleValue( 0 );
}
_ridge_lift_fps_node->setDoubleValue( strength );
}
return;
}
//get the windspeed at ground level
double ground_wind_from_rad = _surface_wind_from_deg_node->getDoubleValue() * SG_DEGREES_TO_RADIANS;
double ground_wind_speed_mps = _surface_wind_speed_node->getDoubleValue() * SG_NM_TO_METER / 3600;
timer -= dt;
if (timer <= 0.0 ) {
// copy values
double user_latitude_rad = _user_latitude_node->getDoubleValue() * SG_DEGREES_TO_RADIANS;
double user_longitude_rad = _user_longitude_node->getDoubleValue() * SG_DEGREES_TO_RADIANS;
SGGeoc myPosition = SGGeoc::fromDegM( probe_lon_deg[0], probe_lat_deg[0], 20000.0 );
double ground_wind_from_rad = _surface_wind_from_deg_node->getDoubleValue() * SG_DEGREES_TO_RADIANS + SG_PI;
double earth_rad_m = _earth_radius_node->getDoubleValue() * SG_FEET_TO_METER;
if( earth_rad_m < SG_EPSILON )
earth_rad_m = SG_EARTH_RAD * 1000;
// probe0 is current position
probe_lat_deg[0] = _user_latitude_node->getDoubleValue();
probe_lon_deg[0] = _user_longitude_node->getDoubleValue();
probe_elev_m[0] = _ground_elev_node->getDoubleValue() * SG_FEET_TO_METER;
// Placing the probes
for (int i = 0; i < sizeof(probe_lat_rad)/sizeof(probe_lat_rad[0]); i++) {
double probe_radius_ratio = dist_probe_m[i]/earth_rad_m;
double sin_probe_radius_ratio = sin(probe_radius_ratio);
probe_lat_rad[i] = asin(sin(user_latitude_rad)*cos(probe_radius_ratio)
+cos(user_latitude_rad)*sin_probe_radius_ratio*cos(ground_wind_from_rad));
if (fabs(fabs(probe_lat_rad[i])-SG_PI/2.0) < SG_EPSILON ) {
probe_lon_rad[i] = user_latitude_rad; // probe on a pole
} else {
probe_lon_rad[i] = fmod((user_longitude_rad+asin(sin(ground_wind_from_rad)
*sin_probe_radius_ratio/cos(probe_lat_rad[i]))+SG_PI)
,SGD_2PI)-SG_PI;
}
probe_lat_deg[i]= probe_lat_rad[i] * SG_RADIANS_TO_DEGREES;
probe_lon_deg[i]= probe_lon_rad[i] * SG_RADIANS_TO_DEGREES;
}
for (int i = 0; i < sizeof(probe_elev_m)/sizeof(probe_elev_m[0]); i++) {
if (!globals->get_scenery()->get_elevation_m(SGGeod::fromGeodM(
SGGeod::fromRad(probe_lon_rad[i],probe_lat_rad[i]), 20000), probe_elev_m[i], 0)) {
probe_elev_m[i] = 0.1;
// compute the remaining probes
for (int i = 1; i < sizeof(probe_lat_deg)/sizeof(probe_lat_deg[0]); i++) {
SGGeoc probe = myPosition.advanceRadM( ground_wind_from_rad, dist_probe_m[i] );
probe_lat_deg[i] = probe.getLatitudeDeg();
probe_lon_deg[i] = probe.getLongitudeDeg();
if (!globals->get_scenery()->get_elevation_m(
SGGeod::fromDegM(probe_lon_deg[i],probe_lat_deg[i], 20000), probe_elev_m[i], NULL )) {
// no ground found? use elevation of previous probe :-(
probe_elev_m[i] = probe_elev_m[i-1];
}
}
// slopes
double adj_slope[4];
double adj_slope[sizeof(slope)];
slope[0] = (probe_elev_m[0] - probe_elev_m[1]) / dist_probe_m[1];
slope[1] = (probe_elev_m[1] - probe_elev_m[2]) / dist_probe_m[2];
slope[2] = (probe_elev_m[2] - probe_elev_m[3]) / dist_probe_m[3];
@ -245,6 +234,7 @@ void FGRidgeLift::update(double dt) {
(user_altitude_agl_m - boundary2_m) / max(probe_elev_m[0],200.0));
}
double ground_wind_speed_mps = _surface_wind_speed_node->getDoubleValue() * SG_NM_TO_METER / 3600;
double lift_mps = lift_factor* ground_wind_speed_mps * agl_factor;
//the updraft, finally, in ft per second

9
src/Environment/ridge_lift.hxx
View file

@ -56,17 +56,13 @@ public:
inline double get_slope( int index ) const { return slope[index]; };
private:
double dist_probe_m[5];
static const double dist_probe_m[5];
double strength;
double timer;
double probe_lat_rad[5];
double probe_lon_rad[5];
double probe_lat_deg[5];
double probe_lon_deg[5];
double probe_elev_m[5];
double slope[4];
@ -79,11 +75,10 @@ private:
SGPropertyNode_ptr _surface_wind_from_deg_node;
SGPropertyNode_ptr _surface_wind_speed_node;
SGPropertyNode_ptr _user_altitude_ft_node;
SGPropertyNode_ptr _user_altitude_agl_ft_node;
SGPropertyNode_ptr _earth_radius_node;
SGPropertyNode_ptr _user_longitude_node;
SGPropertyNode_ptr _user_latitude_node;
SGPropertyNode_ptr _ground_elev_node;
};