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Maintenance: AIThermal

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initialize class members.
SPDX tags.
const variables were appropriate.
eliminate variable shadowing.
spelling.
This commit is contained in:
scttgs0 2023-05-21 21:58:50 -05:00
parent c9d08571c3
commit bb917594d8
2 changed files with 294 additions and 310 deletions
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350
src/AIModel/AIThermal.cxx
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@ -1,24 +1,10 @@
// FGAIThermal - FGAIBase-derived class creates an AI thermal
//
// Copyright (C) 2004  David P. Culp - davidculp2@comcast.net
//
// An attempt to refine the thermal shape and behaviour by WooT 2009
//
// Copyright (C) 2009 Patrice Poly ( WooT )
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License as
// published by the Free Software Foundation; either version 2 of the
// License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
/*
* SPDX-FileName: AIThermal.cxx
* SPDX-FileComment: AIBase-derived class creates an AI thermal. An attempt to refine the thermal shape and behaviour by WooT 2009
* SPDX-FileCopyrightText: Copyright (C) 2004  David P. Culp - davidculp2@comcast.net
* SPDX-FileContributor: Copyright (C) 2009 Patrice Poly ( WooT )
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include <cmath>
#include <string>
@ -36,27 +22,29 @@ FGAIThermal::FGAIThermal() : FGAIBase(object_type::otThermal, false)
max_strength = 6.0;
diameter = 0.5;
strength = factor = 0.0;
cycle_timer = 60*(rand()%31); // some random in the birth time
cycle_timer = 60 * (rand() % 31); // some random in the birth time
ground_elev_ft = 0.0;
dt_count=0.9;
alt=0.0;
dt_count = 0.9;
alt = 0.0;
}
void FGAIThermal::readFromScenario(SGPropertyNode* scFileNode) {
void FGAIThermal::readFromScenario(SGPropertyNode* scFileNode)
{
if (!scFileNode)
return;
FGAIBase::readFromScenario(scFileNode);
setMaxStrength(scFileNode->getDoubleValue("strength-fps", 8.0));
setDiameter(scFileNode->getDoubleValue("diameter-ft", 0.0)/6076.11549);
setDiameter(scFileNode->getDoubleValue("diameter-ft", 0.0) / 6076.11549);
setHeight(scFileNode->getDoubleValue("height-msl", 5000.0));
}
bool FGAIThermal::init(ModelSearchOrder searchOrder) {
bool FGAIThermal::init(ModelSearchOrder searchOrder)
{
factor = 8.0 * max_strength / (diameter * diameter * diameter);
setAltitude( height );
setAltitude(height);
_surface_wind_from_deg_node =
fgGetNode("/environment/config/boundary/entry[0]/wind-from-heading-deg", true);
_surface_wind_speed_node =
@ -69,7 +57,8 @@ bool FGAIThermal::init(ModelSearchOrder searchOrder) {
return FGAIBase::init(searchOrder);
}
void FGAIThermal::bind() {
void FGAIThermal::bind()
{
FGAIBase::bind();
tie("position/altitude-agl-ft", SGRawValuePointer<double>(&altitude_agl_ft));
tie("alt-rel", SGRawValuePointer<double>(&alt_rel));
@ -81,7 +70,8 @@ void FGAIThermal::bind() {
tie("is-dead", SGRawValuePointer<bool>(&is_dead));
}
void FGAIThermal::update(double dt) {
void FGAIThermal::update(double dt)
{
FGAIBase::update(dt);
Run(dt);
Transform();
@ -90,18 +80,19 @@ void FGAIThermal::update(double dt) {
//the formula to get the available portion of VUpMax depending on altitude
//returns a double between 0 and 1
double FGAIThermal::get_strength_fac(double alt_frac) {
double FGAIThermal::get_strength_fac(double alt_frac)
{
double PI = 4.0 * atan(1.0);
double fac = 0.0;
if ( alt_frac <=0.0 ) { // do submarines get thermals ?
if (alt_frac <= 0.0) { // do submarines get thermals ?
fac = 0.0;
} else if ((alt_frac > 0.0) && (alt_frac <= 0.1)) { // ground layer
fac = ( 0.1*( pow( (10.0*alt_frac),10.0) ) );
fac = (0.1 * (pow((10.0 * alt_frac), 10.0)));
} else if ((alt_frac > 0.1) && (alt_frac <= 1.0)) { // main body of the thermal
fac = 0.4175 - 0.5825* ( cos ( PI* (1.0-sqrt(alt_frac) ) +PI) ) ;
fac = 0.4175 - 0.5825 * (cos(PI * (1.0 - sqrt(alt_frac)) + PI));
} else if ((alt_frac > 1.0) && (alt_frac < 1.1)) { //above the ceiling, but not above the cloud
fac = (0.5 * ( 1.0 + cos ( PI*( (-2.0*alt_frac)*5.0 ) ) ) );
fac = (0.5 * (1.0 + cos(PI * ((-2.0 * alt_frac) * 5.0))));
} else if (alt_frac >= 1.1) { //above the cloud
fac = 0.0;
}
@ -110,219 +101,213 @@ double FGAIThermal::get_strength_fac(double alt_frac) {
}
void FGAIThermal::Run(double dt) {
void FGAIThermal::Run(double dt)
{
// *****************************************
// the thermal characteristics and variables
// *****************************************
// *****************************************
// the thermal characteristics and variables
// *****************************************
cycle_timer += dt;
cycle_timer += dt ;
// time
// time
// the time needed for the thermal to be completely formed
const double tmin1 = 5.0;
// the time when the thermal begins to die
const double tmin2 = 20.0;
// the time when the thermal is completely dead
const double tmin3 = 25.0;
const double alive_cycle_time = tmin3 * 60.0;
//the time of the complete cycle, including a period of inactivity
const double tmin4 = 30.0;
// some times expressed in a fraction of tmin3;
const double t1 = tmin1 / tmin3;
const double t2 = tmin2 / tmin3;
const double t3 = 1.0;
const double t4 = tmin4 / tmin3;
// the time elapsed since the thermal was born, in a 0-1 fraction of tmin3
// the time needed for the thermal to be completely formed
double tmin1 = 5.0 ;
// the time when the thermal begins to die
double tmin2 = 20.0 ;
// the time when the thermal is completely dead
double tmin3 = 25.0;
double alive_cycle_time = tmin3*60.0;
//the time of the complete cycle, including a period of inactivity
double tmin4 = 30.0;
// some times expressed in a fraction of tmin3;
double t1 = tmin1/tmin3 ;
double t2 = tmin2/tmin3 ;
double t3 = 1.0 ;
double t4 = tmin4/tmin3;
// the time elapsed since the thermal was born, in a 0-1 fraction of tmin3
time = cycle_timer / alive_cycle_time;
// comment above and uncomment below to freeze the time cycle
// time=0.5;
time = cycle_timer/alive_cycle_time;
// comment above and uncomment below to freeze the time cycle
// time=0.5;
if (time >= t4) {
cycle_timer = 60 * (rand() % 31);
}
if ( time >= t4) {
cycle_timer = 60*(rand()%31);
}
//the position of the thermal 'top'
double thermal_foot_lat = (pos.getLatitudeDeg());
double thermal_foot_lon = (pos.getLongitudeDeg());
//the position of the thermal 'top'
double thermal_foot_lat = (pos.getLatitudeDeg());
double thermal_foot_lon = (pos.getLongitudeDeg());
//the max updraft one can expect in this thermal
double MaxUpdraft=max_strength;
//the max sink one can expect in this thermal, this is a negative number
double MinUpdraft=-max_strength*0.25;
//the fraction of MaxUpdraft one can expect at our height and time
double maxstrengthavail;
//max updraft at the user altitude and time
double v_up_max;
//min updraft at the user altitude and time, this is a negative number
double v_up_min;
double wind_speed;
//the max updraft one can expect in this thermal
double MaxUpdraft = max_strength;
//the max sink one can expect in this thermal, this is a negative number
double MinUpdraft = -max_strength * 0.25;
//the fraction of MaxUpdraft one can expect at our height and time
double maxstrengthavail;
double wind_speed;
//max radius of the the thermal, including the sink area
double Rmax = diameter/2.0;
// 'shaping' of the thermal, the higher, the more conical the thermal- between 0 and 1
double shaping=0.8;
//the radius of the thermal at our altitude in FT, including sink
double Rsink;
//the relative radius of the thermal where we have updraft, between 0 an 1
double r_up_frac=0.9;
//radius of the thermal where we have updraft, in FT
double Rup;
//how far are we from the thermal center at our altitude in FEET
double dist_center;
//max radius of the the thermal, including the sink area
const double Rmax = diameter / 2.0;
// 'shaping' of the thermal, the higher, the more conical the thermal- between 0 and 1
const double shaping = 0.8;
//the radius of the thermal at our altitude in FT, including sink
double Rsink;
//radius of the thermal where we have updraft, in FT
double Rup;
//how far are we from the thermal center at our altitude in FEET
double dist_center;
//the position of the center of the thermal slice at our altitude
double slice_center_lon;
double slice_center_lat;
//the position of the center of the thermal slice at our altitude
double slice_center_lon;
double slice_center_lat;
//we need to know the thermal foot AGL altitude
//we need to know the thermal foot AGL altitude
//we could do this only once, as thermal don't move
//but then agl info is lost on user reset
//so we only do this every 10 seconds to save cpu
dt_count += dt;
if (dt_count >= 10.0 ) {
//we could do this only once, as thermal don't move
//but then agl info is lost on user reset
//so we only do this every 10 seconds to save cpu
dt_count += dt;
if (dt_count >= 10.0) {
if (getGroundElevationM(SGGeod::fromGeodM(pos, 20000), alt, 0)) {
ground_elev_ft = alt * SG_METER_TO_FEET;
do_agl_calc = false;
altitude_agl_ft = height - ground_elev_ft ;
altitude_agl_ft = height - ground_elev_ft;
dt_count = 0.0;
}
}
}
//user altitude relative to the thermal height, seen AGL from the thermal foot
//user altitude relative to the thermal height, seen AGL from the thermal foot
double user_altitude = globals->get_aircraft_position().getElevationFt();
if ( user_altitude < 1.0 ) { user_altitude = 1.0 ;}; // an ugly way to avoid NaNs for users at alt 0
double user_altitude_agl= ( user_altitude - ground_elev_ft ) ;
alt_rel = user_altitude_agl / altitude_agl_ft;
double user_altitude = globals->get_aircraft_position().getElevationFt();
if (user_altitude < 1.0) { user_altitude = 1.0; }; // an ugly way to avoid NaNs for users at alt 0
double user_altitude_agl = (user_altitude - ground_elev_ft);
alt_rel = user_altitude_agl / altitude_agl_ft;
//the updraft user feels !
double Vup;
//the updraft user feels !
double Vup;
// *********************
// environment variables
// *********************
// *********************
// environment variables
// *********************
// the wind heading at the user alt
double wind_heading_rad;
// the wind heading at the user alt
double wind_heading_rad;
// the "ambient" sink outside thermals
double global_sink = -1.0;
// the "ambient" sink outside thermals
double global_sink = -1.0;
// **************
// some constants
// **************
// **************
// some constants
// **************
double PI = 4.0 * atan(1.0);
double PI = 4.0 * atan(1.0);
// ******************
// thermal main cycle
// ******************
// ******************
// thermal main cycle
// ******************
//we get the max strenght proportion we can expect at the time and altitude, formuled between 0 and 1
//double xx;
if (time <= t1) {
xx = ( time / t1 );
maxstrengthavail = xx* get_strength_fac ( alt_rel / xx );
//we get the max strength proportion we can expect at the time and altitude, clamped between 0 and 1
//double xx;
if (time <= t1) {
xx = (time / t1);
maxstrengthavail = xx * get_strength_fac(alt_rel / xx);
is_forming = true;
is_formed = false;
is_dying = false;
is_dead = false;
} else if ((time > t1) && (time <= t2)) {
maxstrengthavail = get_strength_fac ( (alt_rel) );
} else if ((time > t1) && (time <= t2)) {
maxstrengthavail = get_strength_fac((alt_rel));
is_forming = false;
is_formed = true;
is_dying = false;
is_dead = false;
} else if ((time > t2) && (time <= t3)) {
xx= ( ( time - t2) / (1.0 - t2) ) ;
maxstrengthavail = get_strength_fac ( alt_rel - xx );
} else if ((time > t2) && (time <= t3)) {
xx = ((time - t2) / (1.0 - t2));
maxstrengthavail = get_strength_fac(alt_rel - xx);
is_forming = false;
is_formed = false;
is_dying = true;
is_dead = false;
} else {
} else {
maxstrengthavail = 0.0;
is_forming = false;
is_formed = false;
is_dying = false;
is_dead = true;
}
}
//we get the diameter of the thermal slice at the user altitude
//the thermal has a slight conic shape
//we get the diameter of the thermal slice at the user altitude
//the thermal has a slight conic shape
if ((alt_rel >= 0.0) && (alt_rel < 1.0)) {
if ((alt_rel >= 0.0) && (alt_rel < 1.0)) {
Rsink = (shaping * Rmax) + (((1.0 - shaping) * Rmax * alt_rel) / altitude_agl_ft); // in the main thermal body
} else if ((alt_rel >= 1.0) && (alt_rel < 1.1)) {
} else if ((alt_rel >= 1.0) && (alt_rel < 1.1)) {
Rsink = (Rmax / 2.0) * (1.0 + cos((10.0 * PI * alt_rel) - (2.0 * PI))); // above the ceiling
} else {
} else {
Rsink = 0.0; // above the cloud
}
}
//we get the portion of the diameter that produces lift
Rup = r_up_frac * Rsink ;
//we get the portion of the diameter that produces lift
Rup = r_up_frac * Rsink;
//we now determine v_up_max and VupMin depending on our altitude
//we now determine v_up_max and VupMin depending on our altitude
v_up_max = maxstrengthavail * MaxUpdraft;
v_up_min = maxstrengthavail * MinUpdraft;
v_up_max = maxstrengthavail * MaxUpdraft;
v_up_min = maxstrengthavail * MinUpdraft;
// Now we know, for current t and alt, v_up_max, VupMin, Rup, Rsink.
// Now we know, for current t and alt, v_up_max, VupMin, Rup, Rsink.
// We still need to know how far we are from the thermal center
// We still need to know how far we are from the thermal center
// To determine the thermal inclinaison in the wind, we use a ugly approximation,
// in which we say the thermal bends 20° (0.34906 rad ) for 10 kts wind.
// We move the thermal foot upwind, to keep the cloud model over the "center" at ceiling level.
// the displacement distance of the center of the thermal slice, at user altitude,
// and relative to a hipothetical vertical thermal, would be:
// To determine the thermal inclination in the wind, we use a ugly approximation,
// in which we say the thermal bends 20° (0.34906 rad ) for 10 kts wind.
// We move the thermal foot upwind, to keep the cloud model over the "center" at ceiling level.
// the displacement distance of the center of the thermal slice, at user altitude,
// and relative to a hypothetical vertical thermal, would be:
// get surface and 9000 ft wind
// get surface and 9000 ft wind
double ground_wind_from_deg = _surface_wind_from_deg_node->getDoubleValue();
double ground_wind_speed_kts = _surface_wind_speed_node->getDoubleValue();
double aloft_wind_from_deg = _aloft_wind_from_deg_node->getDoubleValue();
double aloft_wind_speed_kts = _aloft_wind_speed_node->getDoubleValue();
double ground_wind_from_deg = _surface_wind_from_deg_node->getDoubleValue();
double ground_wind_speed_kts = _surface_wind_speed_node->getDoubleValue();
double aloft_wind_from_deg = _aloft_wind_from_deg_node->getDoubleValue();
double aloft_wind_speed_kts = _aloft_wind_speed_node->getDoubleValue();
double ground_wind_from_rad = (PI/2.0) - PI*( ground_wind_from_deg/180.0);
double aloft_wind_from_rad = (PI/2.0) - PI*( aloft_wind_from_deg/180.0);
double ground_wind_from_rad = (PI / 2.0) - PI * (ground_wind_from_deg / 180.0);
double aloft_wind_from_rad = (PI / 2.0) - PI * (aloft_wind_from_deg / 180.0);
wind_heading_rad= PI+ 0.5*( ground_wind_from_rad + aloft_wind_from_rad );
wind_heading_rad = PI + 0.5 * (ground_wind_from_rad + aloft_wind_from_rad);
wind_speed = ground_wind_speed_kts + user_altitude * ( (aloft_wind_speed_kts -ground_wind_speed_kts ) / 9000.0 );
wind_speed = ground_wind_speed_kts + user_altitude * ((aloft_wind_speed_kts - ground_wind_speed_kts) / 9000.0);
double dt_center_alt = -(tan (0.034906*wind_speed)) * ( altitude_agl_ft-user_altitude_agl );
double dt_center_alt = -(tan(0.034906 * wind_speed)) * (altitude_agl_ft - user_altitude_agl);
// now, lets find how far we are from this shifted slice
// now, lets find how far we are from this shifted slice
double dt_slice_lon_FT = ( dt_center_alt * cos ( wind_heading_rad ));
double dt_slice_lat_FT = ( dt_center_alt * sin ( wind_heading_rad ));
double dt_slice_lon_FT = (dt_center_alt * cos(wind_heading_rad));
double dt_slice_lat_FT = (dt_center_alt * sin(wind_heading_rad));
double dt_slice_lon = dt_slice_lon_FT / ft_per_deg_lon;
double dt_slice_lat = dt_slice_lat_FT / ft_per_deg_lat;
double dt_slice_lon = dt_slice_lon_FT / ft_per_deg_lon;
double dt_slice_lat = dt_slice_lat_FT / ft_per_deg_lat;
slice_center_lon = thermal_foot_lon + dt_slice_lon;
slice_center_lat = thermal_foot_lat + dt_slice_lat;
slice_center_lon = thermal_foot_lon + dt_slice_lon;
slice_center_lat = thermal_foot_lat + dt_slice_lat;
dist_center = SGGeodesy::distanceNm(SGGeod::fromDeg(slice_center_lon, slice_center_lat),
dist_center = SGGeodesy::distanceNm(SGGeod::fromDeg(slice_center_lon, slice_center_lat),
globals->get_aircraft_position());
// Now we can calculate Vup
// Now we can calculate Vup
if (max_strength >= 0.0) { // this is a thermal
if (max_strength >= 0.0) { // this is a thermal
if ((dist_center >= 0.0) && (dist_center < Rup)) { //user is in the updraft area
Vup = v_up_max * cos(dist_center * PI / (2.0 * Rup));
@ -333,27 +318,26 @@ if (max_strength >= 0.0) { // this is a thermal
} else { // outside the thermal
Vup = global_sink;
}
}
}
else { // this is a sink, we don't want updraft on the sides, nor do we want to feel sink near or above ceiling and ground
else { // this is a sink, we don't want updraft on the sides, nor do we want to feel sink near or above ceiling and ground
if (alt_rel <= 1.1) {
double fac = (1.0 - (1.0 - 1.815 * alt_rel) * (1.0 - 1.815 * alt_rel));
Vup = fac * (global_sink + ((v_up_max - global_sink) / 2.0) * (1.0 + cos(dist_center * PI / Rmax)));
} else {
Vup = global_sink;
}
}
}
//correct for no global sink above clouds and outside thermals
if ( ( (alt_rel > 1.0) && (alt_rel <1.1)) && ( dist_center > Rsink ) ) {
Vup = global_sink * ( 11.0 -10.0 * alt_rel );
}
//correct for no global sink above clouds and outside thermals
if (((alt_rel > 1.0) && (alt_rel < 1.1)) && (dist_center > Rsink)) {
Vup = global_sink * (11.0 - 10.0 * alt_rel);
}
if ( alt_rel >= 1.1 ) {
if (alt_rel >= 1.1) {
Vup = 0.0;
}
strength = Vup;
range = dist_center;
}
strength = Vup;
range = dist_center;
}

30
src/AIModel/AIThermal.hxx
View file

@ -48,21 +48,21 @@ private:
void Run(double dt);
double get_strength_fac(double alt_frac);
double max_strength;
double strength;
double diameter;
double height = 0.0;
double factor;
double alt_rel = 0.0;
double alt;
double v_up_max = 0.0;
double v_up_min = 0.0;
double r_up_frac = 0.0;
double cycle_timer;
double dt_count;
double time = 0.0;
double xx = 0.0;
double ground_elev_ft; // ground level in ft
double max_strength{0.0};
double strength{0.0};
double diameter{0.0};
double height{0.0};
double factor{0.0};
double alt_rel{0.0};
double alt{0.0};
double v_up_max{0.0}; //max updraft at the user altitude and time
double v_up_min{0.0}; //min updraft at the user altitude and time, this is a negative number
double r_up_frac{0.9}; //the relative radius of the thermal where we have updraft, between 0 an 1
double cycle_timer{0.0};
double dt_count{0.0};
double time{0.0};
double xx{0.0};
double ground_elev_ft{0.0}; // ground level in ft
bool do_agl_calc = false;
bool is_forming = false;