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flightgear/src/AIModel/AIAircraft.cxx
ehofman 11290e8022 Remove an unnecessary property set.
2004-06-11 08:09:55 +00:00

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// FGAIAircraft - FGAIBase-derived class creates an AI airplane
//
// Written by David Culp, started October 2003.
//
// Copyright (C) 2003 David P. Culp - davidculp2@comcast.net
//
// 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., 675 Mass Ave, Cambridge, MA 02139, USA.
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <simgear/math/point3d.hxx>
#include <Main/fg_props.hxx>
#include <Main/globals.hxx>
#include <Scenery/scenery.hxx>
#include <string>
#include <math.h>
SG_USING_STD(string);
#include "AIAircraft.hxx"
//
// accel, decel, climb_rate, descent_rate, takeoff_speed, climb_speed,
// cruise_speed, descent_speed, land_speed
//
const FGAIAircraft::PERF_STRUCT FGAIAircraft::settings[] = {
// light aircraft
{2.0, 2.0, 450.0, 1000.0, 70.0, 80.0, 100.0, 80.0, 60.0},
// ww2_fighter
{4.0, 2.0, 3000.0, 1500.0, 110.0, 180.0, 250.0, 200.0, 100.0},
// jet_transport
{5.0, 2.0, 3000.0, 1500.0, 140.0, 300.0, 430.0, 300.0, 130.0},
// jet_fighter
{7.0, 3.0, 4000.0, 2000.0, 150.0, 350.0, 500.0, 350.0, 150.0},
// tanker
{5.0, 2.0, 3000.0, 1500.0, 140.0, 300.0, 430.0, 300.0, 130.0}
};
FGAIAircraft::FGAIAircraft(FGAIManager* mgr) {
manager = mgr;
_type_str = "aircraft";
_otype = otAircraft;
fp = 0;
dt_count = 0;
use_perf_vs = true;
isTanker = false;
// set heading and altitude locks
hdg_lock = false;
alt_lock = false;
}
FGAIAircraft::~FGAIAircraft() {
}
bool FGAIAircraft::init() {
refuel_node = fgGetNode("systems/refuel/contact", true);
return FGAIBase::init();
}
void FGAIAircraft::bind() {
FGAIBase::bind();
/*
props->tie("controls/gear/gear-down",
SGRawValueFunctions<bool>(FGAIAircraft::_getGearDown));
props->getNode("controls/lighting/landing-lights", true)
->alias("controls/gear/gear-down");
*/
}
void FGAIAircraft::unbind() {
FGAIBase::unbind();
// props->untie("controls/gear/gear-down");
// props->getNode("controls/lighting/landing-lights")->unalias();
}
void FGAIAircraft::update(double dt) {
Run(dt);
Transform();
FGAIBase::update(dt);
}
void FGAIAircraft::SetPerformance(const PERF_STRUCT *ps) {
performance = ps;
}
void FGAIAircraft::Run(double dt) {
FGAIAircraft::dt = dt;
if (fp) ProcessFlightPlan(dt);
double turn_radius_ft;
double turn_circum_ft;
double speed_north_deg_sec;
double speed_east_deg_sec;
double ft_per_deg_lon;
double ft_per_deg_lat;
double dist_covered_ft;
double alpha;
// get size of a degree at this latitude
ft_per_deg_lat = 366468.96 - 3717.12 * cos(pos.lat()/SG_RADIANS_TO_DEGREES);
ft_per_deg_lon = 365228.16 * cos(pos.lat() / SG_RADIANS_TO_DEGREES);
// adjust speed
double speed_diff = tgt_speed - speed;
if (fabs(speed_diff) > 0.2) {
if (speed_diff > 0.0) speed += performance->accel * dt;
if (speed_diff < 0.0) {
if (!no_roll) {
speed -= performance->decel * dt * 3;
} else {
speed -= performance->decel * dt;
}
}
}
// convert speed to degrees per second
speed_north_deg_sec = cos( hdg / SG_RADIANS_TO_DEGREES )
* speed * 1.686 / ft_per_deg_lat;
speed_east_deg_sec = sin( hdg / SG_RADIANS_TO_DEGREES )
* speed * 1.686 / ft_per_deg_lon;
// set new position
pos.setlat( pos.lat() + speed_north_deg_sec * dt);
pos.setlon( pos.lon() + speed_east_deg_sec * dt);
// adjust heading based on current bank angle
if (roll != 0.0) {
turn_radius_ft = 0.088362 * speed * speed
/ tan( fabs(roll) / SG_RADIANS_TO_DEGREES );
turn_circum_ft = SGD_2PI * turn_radius_ft;
dist_covered_ft = speed * 1.686 * dt;
alpha = dist_covered_ft / turn_circum_ft * 360.0;
hdg += alpha * sign( roll );
if ( hdg > 360.0 ) hdg -= 360.0;
if ( hdg < 0.0) hdg += 360.0;
}
// adjust target bank angle if heading lock engaged
if (hdg_lock) {
double bank_sense = 0.0;
double diff = fabs(hdg - tgt_heading);
if (diff > 180) diff = fabs(diff - 360);
double sum = hdg + diff;
if (sum > 360.0) sum -= 360.0;
if (fabs(sum - tgt_heading) < 1.0) {
bank_sense = 1.0; // right turn
} else {
bank_sense = -1.0; // left turn
}
if (diff < 30) {
tgt_roll = diff * bank_sense;
} else {
tgt_roll = 30.0 * bank_sense;
}
}
// adjust bank angle, use 9 degrees per second
double bank_diff = tgt_roll - roll;
if (fabs(bank_diff) > 0.2) {
if (bank_diff > 0.0) roll += 9.0 * dt;
if (bank_diff < 0.0) roll -= 9.0 * dt;
}
// adjust altitude (meters) based on current vertical speed (fpm)
altitude += vs / 60.0 * dt;
pos.setelev(altitude * SG_FEET_TO_METER);
double altitude_ft = altitude;
// find target vertical speed if altitude lock engaged
if (alt_lock && use_perf_vs) {
if (altitude_ft < tgt_altitude) {
tgt_vs = tgt_altitude - altitude_ft;
if (tgt_vs > performance->climb_rate)
tgt_vs = performance->climb_rate;
} else {
tgt_vs = tgt_altitude - altitude_ft;
if (tgt_vs < (-performance->descent_rate))
tgt_vs = -performance->descent_rate;
}
}
if (alt_lock && !use_perf_vs) {
double max_vs = 4*(tgt_altitude - altitude);
double min_vs = 100;
if (tgt_altitude < altitude) min_vs = -100.0;
if ((fabs(tgt_altitude - altitude) < 1500.0) &&
(fabs(max_vs) < fabs(tgt_vs))) tgt_vs = max_vs;
if (fabs(tgt_vs) < fabs(min_vs)) tgt_vs = min_vs;
}
// adjust vertical speed
double vs_diff = tgt_vs - vs;
if (fabs(vs_diff) > 10.0) {
if (vs_diff > 0.0) {
vs += 900.0 * dt;
if (vs > tgt_vs) vs = tgt_vs;
} else {
vs -= 400.0 * dt;
if (vs < tgt_vs) vs = tgt_vs;
}
}
// match pitch angle to vertical speed
if (vs > 0){
pitch = vs * 0.005;
} else {
pitch = vs * 0.002;
}
//###########################//
// do calculations for radar //
//###########################//
double radar_range_ft2 = fgGetDouble("/instrumentation/radar/range");
radar_range_ft2 *= SG_NM_TO_METER * SG_METER_TO_FEET;
radar_range_ft2 *= radar_range_ft2;
double user_latitude = manager->get_user_latitude();
double user_longitude = manager->get_user_longitude();
double lat_range = fabs(pos.lat() - user_latitude) * ft_per_deg_lat;
double lon_range = fabs(pos.lon() - user_longitude) * ft_per_deg_lon;
double range_ft2 = lat_range*lat_range + lon_range*lon_range;
//
// Test whether the target is within radar range.
//
in_range = (range_ft2 <= radar_range_ft2);
if ( in_range )
{
props->setBoolValue("radar/in-range", true);
// copy values from the AIManager
double user_altitude = manager->get_user_altitude();
double user_heading = manager->get_user_heading();
double user_pitch = manager->get_user_pitch();
double user_yaw = manager->get_user_yaw();
double user_speed = manager->get_user_speed();
// calculate range to target in feet and nautical miles
double range_ft = sqrt( range_ft2 );
range = range_ft / 6076.11549;
// calculate bearing to target
if (pos.lat() >= user_latitude) {
bearing = atan2(lat_range, lon_range) * SG_RADIANS_TO_DEGREES;
if (pos.lon() >= user_longitude) {
bearing = 90.0 - bearing;
} else {
bearing = 270.0 + bearing;
}
} else {
bearing = atan2(lon_range, lat_range) * SG_RADIANS_TO_DEGREES;
if (pos.lon() >= user_longitude) {
bearing = 180.0 - bearing;
} else {
bearing = 180.0 + bearing;
}
}
// calculate look left/right to target, without yaw correction
horiz_offset = bearing - user_heading;
if (horiz_offset > 180.0) horiz_offset -= 360.0;
if (horiz_offset < -180.0) horiz_offset += 360.0;
// calculate elevation to target
elevation = atan2( altitude_ft - user_altitude, range_ft )
* SG_RADIANS_TO_DEGREES;
// calculate look up/down to target
vert_offset = elevation + user_pitch;
/* this calculation needs to be fixed, but it isn't important anyway
// calculate range rate
double recip_bearing = bearing + 180.0;
if (recip_bearing > 360.0) recip_bearing -= 360.0;
double my_horiz_offset = recip_bearing - hdg;
if (my_horiz_offset > 180.0) my_horiz_offset -= 360.0;
if (my_horiz_offset < -180.0) my_horiz_offset += 360.0;
rdot = (-user_speed * cos( horiz_offset * SG_DEGREES_TO_RADIANS ))
+(-speed * 1.686 * cos( my_horiz_offset * SG_DEGREES_TO_RADIANS ));
*/
// now correct look left/right for yaw
horiz_offset += user_yaw;
// calculate values for radar display
y_shift = range * cos( horiz_offset * SG_DEGREES_TO_RADIANS);
x_shift = range * sin( horiz_offset * SG_DEGREES_TO_RADIANS);
rotation = hdg - user_heading;
if (rotation < 0.0) rotation += 360.0;
}
//************************************//
// Tanker code //
//************************************//
if ( isTanker) {
if ( (range_ft2 < 250.0 * 250.0) &&
(y_shift > 0.0) &&
(elevation > 0.0) ) {
refuel_node->setBoolValue(true);
} else {
refuel_node->setBoolValue(false);
}
}
}
void FGAIAircraft::AccelTo(double speed) {
tgt_speed = speed;
}
void FGAIAircraft::PitchTo(double angle) {
tgt_pitch = angle;
alt_lock = false;
}
void FGAIAircraft::RollTo(double angle) {
tgt_roll = angle;
hdg_lock = false;
}
void FGAIAircraft::YawTo(double angle) {
tgt_yaw = angle;
}
void FGAIAircraft::ClimbTo(double altitude) {
tgt_altitude = altitude;
alt_lock = true;
}
void FGAIAircraft::TurnTo(double heading) {
tgt_heading = heading;
hdg_lock = true;
}
double FGAIAircraft::sign(double x) {
if ( x < 0.0 ) { return -1.0; }
else { return 1.0; }
}
void FGAIAircraft::SetFlightPlan(FGAIFlightPlan *f) {
fp = f;
}
void FGAIAircraft::ProcessFlightPlan( double dt ) {
FGAIFlightPlan::waypoint* prev = 0; // the one behind you
FGAIFlightPlan::waypoint* curr = 0; // the one ahead
FGAIFlightPlan::waypoint* next = 0; // the next plus 1
prev = fp->getPreviousWaypoint();
curr = fp->getCurrentWaypoint();
next = fp->getNextWaypoint();
dt_count += dt;
if (!prev) { //beginning of flightplan, do this initialization once
fp->IncrementWaypoint();
prev = fp->getPreviousWaypoint(); //first waypoint
curr = fp->getCurrentWaypoint(); //second waypoint
next = fp->getNextWaypoint(); //third waypoint (might not exist!)
setLatitude(prev->latitude);
setLongitude(prev->longitude);
setSpeed(prev->speed);
setAltitude(prev->altitude);
setHeading(fp->getBearing(prev->latitude, prev->longitude, curr));
if (next) fp->setLeadDistance(speed, hdg, curr, next);
if (curr->crossat > -1000.0) { //use a calculated descent/climb rate
use_perf_vs = false;
tgt_vs = (curr->crossat - prev->altitude)/
(fp->getDistanceToGo(pos.lat(), pos.lon(), curr)/
6076.0/prev->speed*60.0);
tgt_altitude = curr->crossat;
} else {
use_perf_vs = true;
tgt_altitude = prev->altitude;
}
alt_lock = hdg_lock = true;
no_roll = prev->on_ground;
//cout << "First waypoint: " << prev->name << endl;
//cout << " Target speed: " << tgt_speed << endl;
//cout << " Target altitude: " << tgt_altitude << endl;
//cout << " Target heading: " << tgt_heading << endl << endl;
return;
} // end of initialization
// let's only process the flight plan every 100 ms.
if (dt_count < 0.1) {
return;
} else {
dt_count = 0;
// check to see if we've reached the lead point for our next turn
double dist_to_go = fp->getDistanceToGo(pos.lat(), pos.lon(), curr);
double lead_dist = fp->getLeadDistance();
if (lead_dist < (2*speed)) lead_dist = 2*speed; //don't skip over the waypoint
//cout << "dist_to_go: " << dist_to_go << ", lead_dist: " << lead_dist << endl;
if ( dist_to_go < lead_dist ) {
if (curr->finished) { //end of the flight plan, so terminate
setDie(true);
return;
}
// we've reached the lead-point for the waypoint ahead
if (next) tgt_heading = fp->getBearing(curr, next);
fp->IncrementWaypoint();
prev = fp->getPreviousWaypoint();
curr = fp->getCurrentWaypoint();
next = fp->getNextWaypoint();
if (next) fp->setLeadDistance(speed, tgt_heading, curr, next);
if (curr->crossat > -1000.0) {
use_perf_vs = false;
tgt_vs = (curr->crossat - altitude)/
(fp->getDistanceToGo(pos.lat(), pos.lon(), curr)/6076.0/speed*60.0);
tgt_altitude = curr->crossat;
} else {
use_perf_vs = true;
tgt_altitude = prev->altitude;
}
tgt_speed = prev->speed;
hdg_lock = alt_lock = true;
no_roll = prev->on_ground;
//cout << "Crossing waypoint: " << prev->name << endl;
//cout << " Target speed: " << tgt_speed << endl;
//cout << " Target altitude: " << tgt_altitude << endl;
//cout << " Target heading: " << tgt_heading << endl << endl;
} else {
double calc_bearing = fp->getBearing(pos.lat(), pos.lon(), curr);
double hdg_error = calc_bearing - tgt_heading;
if (fabs(hdg_error) > 1.0) {
TurnTo( calc_bearing );
}
}
}
}
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