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flightgear/src/AIModel/AIShip.cxx
mfranz 002b880e7e Vivian MEAZZA: 
"Implement 'flightplans' for AIShips. This patch also introduces the concept
of a 'WAIT' token for AIShips: when the flightplan reaches a 'WAIT', the
AIShip stops and pauses for the specified time (secs)."
2007-03-05 21:40:39 +00:00

587 lines
17 KiB
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// FGAIShip - FGAIBase-derived class creates an AI ship
//
// Written by David Culp, started October 2003.
// with major amendments and additions by Vivian Meazza, 2004 - 2007
//
// 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.
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#ifdef _MSC_VER
# include <float.h>
# define finite _finite
#elif defined(__sun) || defined(sgi)
# include <ieeefp.h>
#endif
#include <math.h>
#include <simgear/math/sg_geodesy.hxx>
#include <simgear/math/sg_random.h>
#include "AIShip.hxx"
FGAIShip::FGAIShip(object_type ot) :
FGAIBase(ot),
_dt_count(0),
_next_run(0)
{
}
FGAIShip::~FGAIShip() {
}
void FGAIShip::readFromScenario(SGPropertyNode* scFileNode) {
if (!scFileNode)
return;
FGAIBase::readFromScenario(scFileNode);
setRudder(scFileNode->getFloatValue("rudder", 0.0));
setName(scFileNode->getStringValue("name", "Titanic"));
setRadius(scFileNode->getDoubleValue("turn-radius-ft", 2000));
std::string flightplan = scFileNode->getStringValue("flightplan");
setRepeat(scFileNode->getBoolValue("repeat", false));
if (!flightplan.empty()) {
FGAIFlightPlan* fp = new FGAIFlightPlan(flightplan);
setFlightPlan(fp);
}
}
bool FGAIShip::init(bool search_in_AI_path) {
prev = 0; // the one behind you
curr = 0; // the one ahead
next = 0; // the next plus 1
props->setStringValue("name", _name.c_str());
props->setStringValue("position/waypoint-name-prev", _prev_name.c_str());
props->setStringValue("position/waypoint-name-curr", _curr_name.c_str());
props->setStringValue("position/waypoint-name-next", _next_name.c_str());
_hdg_lock = false;
_rudder = 0.0;
no_roll = false;
_rudder_constant = 0.5;
_roll_constant = 0.001;
_speed_constant = 0.05;
_hdg_constant = 0.01;
_rd_turn_radius_ft = _sp_turn_radius_ft = turn_radius_ft;
_fp_init = false;
_missed = false;
_waiting = false;
_new_waypoint = true;
_missed_count = 0;
_wait_count = 0;
_missed_time_sec = 30;
_wp_range = _old_range = 0;
_range_rate = 0;
if (fp)
_fp_init = initFlightPlan();
return FGAIBase::init(search_in_AI_path);
}
void FGAIShip::bind() {
FGAIBase::bind();
props->tie("surface-positions/rudder-pos-deg",
SGRawValuePointer<float>(&_rudder));
props->tie("controls/heading-lock",
SGRawValuePointer<bool>(&_hdg_lock));
props->tie("controls/tgt-speed-kts",
SGRawValuePointer<double>(&tgt_speed));
props->tie("controls/tgt-heading-degs",
SGRawValuePointer<double>(&tgt_heading));
props->tie("controls/constants/rudder",
SGRawValuePointer<double>(&_rudder_constant));
props->tie("controls/constants/roll",
SGRawValuePointer<double>(&_roll_constant));
props->tie("controls/constants/rudder",
SGRawValuePointer<double>(&_rudder_constant));
props->tie("controls/constants/speed",
SGRawValuePointer<double>(&_speed_constant));
props->tie("position/waypoint-range-nm",
SGRawValuePointer<double>(&_wp_range));
props->tie("position/waypoint-range-old-nm",
SGRawValuePointer<double>(&_old_range));
props->tie("position/waypoint-range-rate-nm-sec",
SGRawValuePointer<double>(&_range_rate));
props->tie("position/waypoint-new",
SGRawValuePointer<bool>(&_new_waypoint));
props->tie("position/waypoint-missed",
SGRawValuePointer<bool>(&_missed));
props->tie("position/waypoint-missed-count",
SGRawValuePointer<double>(&_missed_count));
props->tie("position/waypoint-missed-time-sec",
SGRawValuePointer<double>(&_missed_time_sec));
props->tie("position/waypoint-wait-count",
SGRawValuePointer<double>(&_wait_count));
props->tie("position/waypoint-waiting",
SGRawValuePointer<bool>(&_waiting));
}
void FGAIShip::unbind() {
FGAIBase::unbind();
props->untie("surface-positions/rudder-pos-deg");
props->untie("controls/heading-lock");
props->untie("controls/tgt-speed-kts");
props->untie("controls/tgt-heading-degs");
props->untie("controls/constants/roll");
props->untie("controls/constants/rudder");
props->untie("controls/constants/speed");
props->untie("position/waypoint-range-nm");
props->untie("position/waypoint-range-old-nm");
props->untie("position/waypoint-range-rate-nm-sec");
props->untie("position/waypoint-new");
props->untie("position/waypoint-missed");
props->untie("position/waypoint-wait-count");
props->untie("position/waypoint-waiting");
props->untie("position/waypoint-missed-time-sec");
}
void FGAIShip::update(double dt) {
FGAIBase::update(dt);
Run(dt);
Transform();
}
void FGAIShip::Run(double dt) {
if (_fp_init)
ProcessFlightPlan(dt);
double speed_north_deg_sec;
double speed_east_deg_sec;
double alpha;
double rudder_limit;
double raw_roll;
// adjust speed
double speed_diff = tgt_speed - speed;
if (fabs(speed_diff) > 0.1) {
if (speed_diff > 0.0)
speed += _speed_constant * dt;
if (speed_diff < 0.0)
speed -= _speed_constant * dt;
}
// do not allow unreasonable ship speeds
if (speed > 40)
speed = 40;
// convert speed to degrees per second
speed_north_deg_sec = cos(hdg / SGD_RADIANS_TO_DEGREES)
* speed * 1.686 / ft_per_deg_lat;
speed_east_deg_sec = sin(hdg / SGD_RADIANS_TO_DEGREES)
* speed * 1.686 / ft_per_deg_lon;
// set new position
pos.setLatitudeDeg(pos.getLatitudeDeg() + speed_north_deg_sec * dt);
pos.setLongitudeDeg(pos.getLongitudeDeg() + speed_east_deg_sec * dt);
// adjust heading based on current _rudder angle
//cout << "turn_radius_ft " << turn_radius_ft ;
if (turn_radius_ft <= 0)
turn_radius_ft = 0; // don't allow nonsense values
if (_rudder > 45)
_rudder = 45;
if (_rudder < -45)
_rudder = -45;
//we assume that at slow speed ships will manoeuvre using engines/bow thruster
if (fabs(speed)<=5)
_sp_turn_radius_ft = 500;
else
// adjust turn radius for speed. The equation is very approximate.
// we need to allow for negative speeds
_sp_turn_radius_ft = 10 * pow ((fabs(speed) - 15), 2) + turn_radius_ft;
//cout << " speed turn radius " << _sp_turn_radius_ft ;
if (_rudder <= -0.25 || _rudder >= 0.25) {
// adjust turn radius for _rudder angle. The equation is even more approximate.
float a = 19;
float b = -0.2485;
float c = 0.543;
_rd_turn_radius_ft = (a * exp(b * fabs(_rudder)) + c) * _sp_turn_radius_ft;
//cout <<" _rudder turn radius " << _rd_turn_radius_ft << endl;
// calculate the angle, alpha, subtended by the arc traversed in time dt
alpha = ((speed * 1.686 * dt) / _rd_turn_radius_ft) * SG_RADIANS_TO_DEGREES;
// make sure that alpha is applied in the right direction
hdg += alpha * sign(_rudder);
if (hdg > 360.0)
hdg -= 360.0;
if (hdg < 0.0)
hdg += 360.0;
//adjust roll for _rudder angle and speed. Another bit of voodoo
raw_roll = -0.0166667 * speed * _rudder;
} else {
// _rudder angle is 0
raw_roll = 0;
}
//low pass filter
if (speed < 0)
roll = -roll;
roll = (raw_roll * _roll_constant) + (roll * (1 - _roll_constant));
// adjust target _rudder angle if heading lock engaged
if (_hdg_lock) {
double rudder_sense = 0.0;
double diff = fabs(hdg - tgt_heading);
//cout << "_rudder diff" << diff << endl;
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)
rudder_sense = 1.0;
else
rudder_sense = -1.0;
if (speed < 0)
rudder_sense = -rudder_sense;
if (diff < 15)
_tgt_rudder = diff * rudder_sense;
else
_tgt_rudder = 45 * rudder_sense;
}
// adjust _rudder angle
double rudder_diff = _tgt_rudder - _rudder;
// set the _rudder limit by speed
if (speed <= 40)
rudder_limit = (-0.825 * speed) + 35;
else
rudder_limit = 2;
if (fabs(rudder_diff)> 0.1) { // apply dead zone
if (rudder_diff > 0.0) {
_rudder += _rudder_constant * dt;
if (_rudder > rudder_limit) // apply the _rudder limit
_rudder = rudder_limit;
} else if (rudder_diff < 0.0) {
_rudder -= _rudder_constant * dt;
if (_rudder < -rudder_limit)
_rudder = -rudder_limit;
}
}
}//end function
void FGAIShip::AccelTo(double speed) {
tgt_speed = speed;
}
void FGAIShip::PitchTo(double angle) {
tgt_pitch = angle;
}
void FGAIShip::RollTo(double angle) {
tgt_roll = angle;
}
void FGAIShip::YawTo(double angle) {
}
void FGAIShip::ClimbTo(double altitude) {
}
void FGAIShip::TurnTo(double heading) {
tgt_heading = heading;
_hdg_lock = true;
}
double FGAIShip::sign(double x) {
if (x < 0.0)
return -1.0;
else
return 1.0;
}
void FGAIShip::setFlightPlan(FGAIFlightPlan* f) {
fp = f;
}
void FGAIShip::setName(const string& n) {
_name = n;
}
void FGAIShip::setCurrName(const string& c) {
_curr_name = c;
props->setStringValue("position/waypoint-name-curr", _curr_name.c_str());
}
void FGAIShip::setNextName(const string& n) {
_next_name = n;
props->setStringValue("position/waypoint-name-next", _next_name.c_str());
}
void FGAIShip::setPrevName(const string& p) {
_prev_name = p;
props->setStringValue("position/waypoint-name-prev", _prev_name.c_str());
}
void FGAIShip::setRepeat(bool r) {
_repeat = r;
}
void FGAIShip::setMissed(bool m) {
_missed = m;
props->setBoolValue("position/waypoint-missed", _missed);
}
void FGAIShip::ProcessFlightPlan(double dt) {
_missed = false;
_dt_count += dt;
///////////////////////////////////////////////////////////////////////////
// Check Execution time (currently once every 1 sec)
// Add a bit of randomization to prevent the execution of all flight plans
// in synchrony, which can add significant periodic framerate flutter.
///////////////////////////////////////////////////////////////////////////
if (_dt_count < _next_run)
return;
_next_run = 1.0 + (0.5 * sg_random());
// check to see if we've reached the point for our next turn
// if the range to the waypoint is less than the calculated turn
// radius we can start the turn to the next leg
_wp_range = getRange(pos.getLatitudeDeg(), pos.getLongitudeDeg(), curr->latitude, curr->longitude);
_range_rate = (_wp_range - _old_range) / _dt_count;
double sp_turn_radius_nm = _sp_turn_radius_ft / 6076.1155;
// we need to try to identify a _missed waypoint
// calculate the time needed to turn through an arc of 90 degrees, and allow an error of 30 secs
if (speed != 0)
_missed_time_sec = 30 + ((SGD_PI * sp_turn_radius_nm * 60 * 60) / (2 * fabs(speed)));
else
_missed_time_sec = 30;
if ((_range_rate > 0) && (_wp_range < 3 * sp_turn_radius_nm) && !_new_waypoint)
_missed_count += _dt_count;
if (_missed_count >= _missed_time_sec) {
setMissed(true);
} else {
setMissed(false);
}
_old_range = _wp_range;
if ((_wp_range < sp_turn_radius_nm) || _missed || _waiting && !_new_waypoint) {
if (_next_name == "END") {
if (_repeat) {
SG_LOG(SG_GENERAL, SG_INFO, "AIShip: Flightplan restarting ");
fp->restart();
prev = curr;
curr = fp->getCurrentWaypoint();
next = fp->getNextWaypoint();
setWPNames();
_wp_range = getRange(pos.getLatitudeDeg(), pos.getLongitudeDeg(), curr->latitude, curr->longitude);
_old_range = _wp_range;
_range_rate = 0;
_new_waypoint = true;
_missed_count = 0;
AccelTo(prev->speed);
} else {
SG_LOG(SG_GENERAL, SG_INFO, "AIShip: Flightplan dieing ");
setDie(true);
_dt_count = 0;
return;
}
} else if (_next_name == "WAIT") {
if (_wait_count < next->wait_time) {
SG_LOG(SG_GENERAL, SG_INFO, "AIShip: " << _name << " _waiting ");
setSpeed(0);
_waiting = true;
_wait_count += _dt_count;
_dt_count = 0;
return;
} else {
SG_LOG(SG_GENERAL, SG_INFO, "AIShip: " << _name << " wait done: getting new waypoints ");
prev = curr;
fp->IncrementWaypoint(false);
fp->IncrementWaypoint(false); // do it twice
curr = fp->getCurrentWaypoint();
next = fp->getNextWaypoint();
_waiting = false;
_wait_count = 0;
}
} else {
//now reorganise the waypoints, so that next becomes current and so on
SG_LOG(SG_GENERAL, SG_INFO, "AIShip: " << _name << " getting new waypoints ");
fp->IncrementWaypoint(false);
prev = fp->getPreviousWaypoint(); //first waypoint
curr = fp->getCurrentWaypoint(); //second waypoint
next = fp->getNextWaypoint(); //third waypoint (might not exist!)
}
setWPNames();
_new_waypoint = true;
_missed_count = 0;
_range_rate = 0;
_wp_range = getRange(pos.getLatitudeDeg(), pos.getLongitudeDeg(), curr->latitude, curr->longitude);
_old_range = _wp_range;
AccelTo(prev->speed);
} else {
_new_waypoint = false;
}
// now revise the required course for the next way point
double course = getCourse(pos.getLatitudeDeg(), pos.getLongitudeDeg(), curr->latitude, curr->longitude);
if (finite(course))
TurnTo(course);
else
SG_LOG(SG_GENERAL, SG_ALERT, "AIShip: Bearing or Range is not a finite number");
_dt_count = 0;
} // end Processing FlightPlan
void FGAIShip::setRudder(float r) {
_rudder = r;
}
void FGAIShip::setRoll(double rl) {
roll = rl;
}
double FGAIShip::getRange(double lat, double lon, double lat2, double lon2) const {
double course, distance, az2;
//calculate the bearing and range of the second pos from the first
geo_inverse_wgs_84(lat, lon, lat2, lon2, &course, &az2, &distance);
distance *= SG_METER_TO_NM;
return distance;
}
double FGAIShip::getCourse(double lat, double lon, double lat2, double lon2) const {
double course, distance, recip;
//calculate the bearing and range of the second pos from the first
geo_inverse_wgs_84(lat, lon, lat2, lon2, &course, &recip, &distance);
if (tgt_speed >= 0) {
return course;
} else {
return recip;
}
}
bool FGAIShip::initFlightPlan() {
SG_LOG(SG_GENERAL, SG_ALERT, "AIShip: " << _name << " initialising waypoints ");
fp->restart();
fp->IncrementWaypoint(false);
prev = fp->getPreviousWaypoint(); //first waypoint
curr = fp->getCurrentWaypoint(); //second waypoint
next = fp->getNextWaypoint(); //third waypoint (might not exist!)
if (curr->name == "WAIT") { // don't wait when initialising
SG_LOG(SG_GENERAL, SG_ALERT, "AIShip: " << _name << " re-initialising waypoints ");
fp->IncrementWaypoint(false);
curr = fp->getCurrentWaypoint();
next = fp->getNextWaypoint();
}
setWPNames();
setLatitude(prev->latitude);
setLongitude(prev->longitude);
setSpeed(prev->speed);
setHeading(getCourse(prev->latitude, prev->longitude, curr->latitude, curr->longitude));
_hdg_lock = true;
_wp_range = getRange(pos.getLatitudeDeg(), pos.getLongitudeDeg(), curr->latitude, curr->longitude);
_old_range = _wp_range;
_range_rate = 0;
_missed = false;
_missed_count = 0;
_new_waypoint = true;
SG_LOG(SG_GENERAL, SG_INFO, "AIShip: " << _name << " done initialising waypoints ");
if (prev)
return true;
else
return false;
} // end of initialization
void FGAIShip::setWPNames() {
if (prev != 0)
setPrevName(prev->name);
else
setPrevName("");
setCurrName(curr->name);
if (next != 0)
setNextName(next->name);
else
setNextName("");
SG_LOG(SG_GENERAL, SG_INFO, "AIShip: prev wp name " << prev->name);
SG_LOG(SG_GENERAL, SG_INFO, "AIShip: current wp name " << curr->name);
SG_LOG(SG_GENERAL, SG_INFO, "AIShip: next wp name " << next->name);
}
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