/******************************************************************************
* AIFlightPlanCreate.cxx
* Written by Durk Talsma, started May, 2004.
*
* 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
#include <cstdlib>
#include <cstdio>
#include "AIFlightPlan.hxx"
#include <simgear/math/sg_geodesy.hxx>
#include <simgear/props/props.hxx>
#include <simgear/props/props_io.hxx>
#include <Airports/airport.hxx>
#include <Airports/runways.hxx>
#include <Airports/dynamics.hxx>
#include "AIAircraft.hxx"
#include "performancedata.hxx"
#include <Environment/environment_mgr.hxx>
#include <Environment/environment.hxx>
#include <FDM/LaRCsim/basic_aero.h>
#include <Navaids/navrecord.hxx>
using std::string;
/* FGAIFlightPlan::create()
* dynamically create a flight plan for AI traffic, based on data provided by the
* Traffic Manager, when reading a filed flightplan failes. (DT, 2004/07/10)
*
* This is the top-level function, and the only one that is publicly available.
*
*/
// Check lat/lon values during initialization;
bool FGAIFlightPlan::create(FGAIAircraft * ac, FGAirport * dep,
FGAirport * arr, int legNr, double alt,
double speed, double latitude,
double longitude, bool firstFlight,
double radius, const string & fltType,
const string & aircraftType,
const string & airline, double distance)
{
bool retVal = true;
int currWpt = wpt_iterator - waypoints.begin();
switch (legNr) {
case 1:
retVal = createPushBack(ac, firstFlight, dep,
radius, fltType, aircraftType, airline);
// Pregenerate the taxi leg.
//if (retVal) {
// waypoints.back()->setName( waypoints.back()->getName() + string("legend"));
// retVal = createTakeoffTaxi(ac, false, dep, radius, fltType, aircraftType, airline);
//}
break;
case 2:
retVal = createTakeoffTaxi(ac, firstFlight, dep, radius, fltType,
aircraftType, airline);
break;
case 3:
retVal = createTakeOff(ac, firstFlight, dep, speed, fltType);
break;
case 4:
retVal = createClimb(ac, firstFlight, dep, arr, speed, alt, fltType);
break;
case 5:
retVal = createCruise(ac, firstFlight, dep, arr, latitude, longitude, speed,
alt, fltType);
break;
case 6:
retVal = createDescent(ac, arr, latitude, longitude, speed, alt, fltType,
distance);
break;
case 7:
retVal = createLanding(ac, arr, fltType);
break;
case 8:
retVal = createLandingTaxi(ac, arr, radius, fltType, aircraftType, airline);
break;
case 9:
retVal = createParking(ac, arr, radius);
break;
default:
//exit(1);
SG_LOG(SG_AI, SG_ALERT,
"AIFlightPlan::create() attempting to create unknown leg"
" this is probably an internal program error");
break;
}
wpt_iterator = waypoints.begin() + currWpt;
//don't increment leg right away, but only once we pass the actual last waypoint that was created.
// to do so, mark the last waypoint with a special status flag
if (retVal) {
waypoints.back()->setName( waypoints.back()->getName() + string("legend"));
// "It's pronounced Leg-end" (Roger Glover (Deep Purple): come Hell or High Water DvD, 1993)
}
//leg++;
return retVal;
}
FGAIWaypoint * FGAIFlightPlan::createOnGround(FGAIAircraft * ac,
const std::string & aName,
const SGGeod & aPos, double aElev,
double aSpeed)
{
FGAIWaypoint *wpt = new FGAIWaypoint;
wpt->setName (aName );
wpt->setLongitude (aPos.getLongitudeDeg() );
wpt->setLatitude (aPos.getLatitudeDeg() );
wpt->setAltitude (aElev );
wpt->setSpeed (aSpeed );
wpt->setCrossat (-10000.1 );
wpt->setGear_down (true );
wpt->setFlaps_down (true );
wpt->setFinished (false );
wpt->setOn_ground (true );
wpt->setRouteIndex (0 );
return wpt;
}
FGAIWaypoint * FGAIFlightPlan::createInAir(FGAIAircraft * ac,
const std::string & aName,
const SGGeod & aPos, double aElev,
double aSpeed)
{
FGAIWaypoint * wpt = createOnGround(ac, aName, aPos, aElev, aSpeed);
wpt->setGear_down (false );
wpt->setFlaps_down (false );
wpt->setOn_ground (false );
wpt->setCrossat (aElev );
return wpt;
}
FGAIWaypoint * FGAIFlightPlan::clone(FGAIWaypoint * aWpt)
{
FGAIWaypoint *wpt = new FGAIWaypoint;
wpt->setName ( aWpt->getName () );
wpt->setLongitude ( aWpt->getLongitude() );
wpt->setLatitude ( aWpt->getLatitude() );
wpt->setAltitude ( aWpt->getAltitude() );
wpt->setSpeed ( aWpt->getSpeed() );
wpt->setCrossat ( aWpt->getCrossat() );
wpt->setGear_down ( aWpt->getGear_down() );
wpt->setFlaps_down ( aWpt->getFlaps_down() );
wpt->setFinished ( aWpt->isFinished() );
wpt->setOn_ground ( aWpt->getOn_ground() );
wpt->setRouteIndex ( 0 );
return wpt;
}
FGAIWaypoint * FGAIFlightPlan::cloneWithPos(FGAIAircraft * ac, FGAIWaypoint * aWpt,
const std::string & aName,
const SGGeod & aPos)
{
FGAIWaypoint *wpt = clone(aWpt);
wpt->setName ( aName );
wpt->setLongitude ( aPos.getLongitudeDeg () );
wpt->setLatitude ( aPos.getLatitudeDeg () );
return wpt;
}
void FGAIFlightPlan::createDefaultTakeoffTaxi(FGAIAircraft * ac,
FGAirport * aAirport,
FGRunway * aRunway)
{
SGGeod runwayTakeoff = aRunway->pointOnCenterline(5.0);
double airportElev = aAirport->getElevation();
FGAIWaypoint *wpt;
wpt =
createOnGround(ac, "Airport Center", aAirport->geod(), airportElev,
ac->getPerformance()->vTaxi());
pushBackWaypoint(wpt);
wpt =
createOnGround(ac, "Runway Takeoff", runwayTakeoff, airportElev,
ac->getPerformance()->vTaxi());
pushBackWaypoint(wpt);
}
bool FGAIFlightPlan::createTakeoffTaxi(FGAIAircraft * ac, bool firstFlight,
FGAirport * apt,
double radius,
const string & fltType,
const string & acType,
const string & airline)
{
// If this function is called during initialization,
// make sure we obtain a valid gate ID first
// and place the model at the location of the gate.
if (firstFlight)
{
gate = apt->getDynamics()->getAvailableParking(radius, fltType,
acType, airline);
if (!gate.isValid()) {
SG_LOG(SG_AI, SG_WARN, "Could not find parking for a " <<
acType <<
" of flight type " << fltType <<
" of airline " << airline <<
" at airport " << apt->getId());
}
}
const string& rwyClass = getRunwayClassFromTrafficType(fltType);
// Only set this if it hasn't been set by ATC already.
if (activeRunway.empty()) {
//cerr << "Getting runway for " << ac->getTrafficRef()->getCallSign() << " at " << apt->getId() << endl;
double depHeading = ac->getTrafficRef()->getCourse();
apt->getDynamics()->getActiveRunway(rwyClass, 1, activeRunway,
depHeading);
}
FGRunway * rwy = apt->getRunwayByIdent(activeRunway);
assert( rwy != NULL );
SGGeod runwayTakeoff = rwy->pointOnCenterline(5.0);
FGGroundNetwork *gn = apt->getDynamics()->getGroundNetwork();
if (!gn->exists()) {
createDefaultTakeoffTaxi(ac, apt, rwy);
return true;
}
PositionedID runwayId = 0;
if (gn->getVersion() > 0) {
runwayId = gn->findNearestNodeOnRunway(runwayTakeoff);
} else {
runwayId = gn->findNearestNode(runwayTakeoff);
}
// A negative gateId indicates an overflow parking, use a
// fallback mechanism for this.
// Starting from gate 0 in this case is a bit of a hack
// which requires a more proper solution later on.
// delete taxiRoute;
// taxiRoute = new FGTaxiRoute;
// Determine which node to start from.
PositionedID node = 0;
// Find out which node to start from
FGParking *park = gate.parking();
if (park) {
node = park->getPushBackPoint();
if (node == -1) {
node = park->guid();
} else if (node == 0) {
// Handle case where parking doesn't have a node
if (firstFlight) {
node = park->guid();
} else {
node = lastNodeVisited;
}
}
}
FGTaxiRoute taxiRoute;
if ( runwayId != 0 )
taxiRoute = gn->findShortestRoute(node, runwayId);
if (taxiRoute.empty()) {
createDefaultTakeoffTaxi(ac, apt, rwy);
return true;
}
taxiRoute.first();
//bool isPushBackPoint = false;
if (firstFlight) {
// If this is called during initialization, randomly
// skip a number of waypoints to get a more realistic
// taxi situation.
int nrWaypointsToSkip = rand() % taxiRoute.size();
// but make sure we always keep two active waypoints
// to prevent a segmentation fault
for (int i = 0; i < nrWaypointsToSkip - 3; i++) {
taxiRoute.next(&node);
}
gate.release(); // free up our gate as required
} else {
if (taxiRoute.size() > 1) {
taxiRoute.next(&node); // chop off the first waypoint, because that is already the last of the pushback route
}
}
// push each node on the taxi route as a waypoint
// int route;
//cerr << "Building taxi route" << endl;
// Note that the line wpt->setRouteIndex was commented out by revision [afcdbd] 2012-01-01,
// which breaks the rendering functions.
// These can probably be generated on the fly however.
while (taxiRoute.next(&node)) {
char buffer[10];
snprintf(buffer, 10, "%lld", (long long int) node);
FGTaxiNode *tn =
apt->getDynamics()->getGroundNetwork()->findNode(node);
FGAIWaypoint *wpt =
createOnGround(ac, buffer, tn->geod(), apt->getElevation(),
ac->getPerformance()->vTaxi());
// TODO: find an alternative way to pass route information to the waypoint.
//wpt->setRouteIndex(route);
//cerr << "Nodes left " << taxiRoute->nodesLeft() << " ";
if (taxiRoute.nodesLeft() == 1) {
// Note that we actually have hold points in the ground network, but this is just an initial test.
//cerr << "Setting departurehold point: " << endl;
wpt->setName( wpt->getName() + string("DepartureHold"));
}
if (taxiRoute.nodesLeft() == 0) {
wpt->setName(wpt->getName() + string("Accel"));
}
pushBackWaypoint(wpt);
}
// Acceleration point, 105 meters into the runway,
SGGeod accelPoint = rwy->pointOnCenterline(105.0);
FGAIWaypoint *wpt = createOnGround(ac, "accel", accelPoint, apt->getElevation(), ac->getPerformance()->vRotate());
pushBackWaypoint(wpt);
//cerr << "[done]" << endl;
return true;
}
void FGAIFlightPlan::createDefaultLandingTaxi(FGAIAircraft * ac,
FGAirport * aAirport)
{
SGGeod lastWptPos =
SGGeod::fromDeg(waypoints.back()->getLongitude(),
waypoints.back()->getLatitude());
double airportElev = aAirport->getElevation();
FGAIWaypoint *wpt;
wpt =
createOnGround(ac, "Runway Exit", lastWptPos, airportElev,
ac->getPerformance()->vTaxi());
pushBackWaypoint(wpt);
wpt =
createOnGround(ac, "Airport Center", aAirport->geod(), airportElev,
ac->getPerformance()->vTaxi());
pushBackWaypoint(wpt);
if (gate.isValid()) {
wpt = createOnGround(ac, "ENDtaxi", gate.parking()->geod(), airportElev,
ac->getPerformance()->vTaxi());
pushBackWaypoint(wpt);
}
}
bool FGAIFlightPlan::createLandingTaxi(FGAIAircraft * ac, FGAirport * apt,
double radius,
const string & fltType,
const string & acType,
const string & airline)
{
gate = apt->getDynamics()->getAvailableParking(radius, fltType,
acType, airline);
SGGeod lastWptPos = waypoints.back()->getPos();
FGGroundNetwork *gn = apt->getDynamics()->getGroundNetwork();
// Find a route from runway end to parking/gate.
if (!gn->exists()) {
createDefaultLandingTaxi(ac, apt);
return true;
}
PositionedID runwayId = 0;
if (gn->getVersion() == 1) {
runwayId = gn->findNearestNodeOnRunway(lastWptPos);
} else {
runwayId = gn->findNearestNode(lastWptPos);
}
//cerr << "Using network node " << runwayId << endl;
// A negative gateId indicates an overflow parking, use a
// fallback mechanism for this.
// Starting from gate 0 doesn't work, so don't try it
FGTaxiRoute taxiRoute;
if (gate.isValid())
taxiRoute = gn->findShortestRoute(runwayId, gate.parking()->guid());
if (taxiRoute.empty()) {
createDefaultLandingTaxi(ac, apt);
return true;
}
PositionedID node;
taxiRoute.first();
int size = taxiRoute.size();
// Omit the last two waypoints, as
// those are created by createParking()
// int route;
for (int i = 0; i < size - 2; i++) {
taxiRoute.next(&node);
char buffer[10];
snprintf(buffer, 10, "%lld", (long long int) node);
FGTaxiNode *tn = gn->findNode(node);
FGAIWaypoint *wpt =
createOnGround(ac, buffer, tn->geod(), apt->getElevation(),
ac->getPerformance()->vTaxi());
//TODO: find an alternative way to pass route information to the waypoint.
//wpt->setRouteIndex(route);
pushBackWaypoint(wpt);
}
return true;
}
static double accelDistance(double v0, double v1, double accel)
{
double t = fabs(v1 - v0) / accel; // time in seconds to change velocity
// area under the v/t graph: (t * v0) + (dV / 2t) where (dV = v1 - v0)
return t * 0.5 * (v1 + v0);
}
// find the horizontal distance to gain the specific altiude, holding
// a constant pitch angle. Used to compute distance based on standard FD/AP
// PITCH mode prior to VS or CLIMB engaging. Visually, we want to avoid
// a dip in the nose angle after rotation, during initial climb-out.
static double pitchDistance(double pitchAngleDeg, double altGainM)
{
return altGainM / tan(pitchAngleDeg * SG_DEGREES_TO_RADIANS);
}
/*******************************************************************
* CreateTakeOff
* A note on units:
* - Speed -> knots -> nm/hour
* - distance along runway =-> meters
* - accel / decel -> is given as knots/hour, but this is highly questionable:
* for a jet_transport performance class, a accel / decel rate of 5 / 2 is
* given respectively. According to performance data.cxx, a value of kts / second seems
* more likely however.
*
******************************************************************/
bool FGAIFlightPlan::createTakeOff(FGAIAircraft * ac, bool firstFlight,
FGAirport * apt, double speed,
const string & fltType)
{
const double ACCEL_POINT = 105.0;
// climb-out angle in degrees. could move this to the perf-db but this
// value is pretty sane
const double INITIAL_PITCH_ANGLE = 10.0;
double accel = ac->getPerformance()->acceleration();
double vTaxi = ac->getPerformance()->vTaxi();
double vRotate = ac->getPerformance()->vRotate();
double vTakeoff = ac->getPerformance()->vTakeoff();
double accelMetric = accel * SG_KT_TO_MPS;
double vTaxiMetric = vTaxi * SG_KT_TO_MPS;
double vRotateMetric = vRotate * SG_KT_TO_MPS;
FGAIWaypoint *wpt;
// Get the current active runway, based on code from David Luff
// This should actually be unified and extended to include
// Preferential runway use schema's
// NOTE: DT (2009-01-18: IIRC, this is currently already the case,
// because the getActive runway function takes care of that.
if (firstFlight) {
const string& rwyClass = getRunwayClassFromTrafficType(fltType);
double heading = ac->getTrafficRef()->getCourse();
apt->getDynamics()->getActiveRunway(rwyClass, 1, activeRunway,
heading);
}
FGRunway * rwy = apt->getRunwayByIdent(activeRunway);
assert( rwy != NULL );
double airportElev = apt->getElevation();
double d = accelDistance(vTaxiMetric, vRotateMetric, accelMetric) + ACCEL_POINT;
SGGeod accelPoint = rwy->pointOnCenterline(d);
wpt = createOnGround(ac, "rotate", accelPoint, airportElev, vTakeoff);
pushBackWaypoint(wpt);
double vRef = vTakeoff + 20; // climb-out at v2 + 20kts
double gearUpDist = d + pitchDistance(INITIAL_PITCH_ANGLE, 400 * SG_FEET_TO_METER);
accelPoint = rwy->pointOnCenterline(gearUpDist);
wpt = cloneWithPos(ac, wpt, "gear-up", accelPoint);
wpt->setSpeed(vRef);
wpt->setCrossat(airportElev + 400);
wpt->setOn_ground(false);
wpt->setGear_down(false);
pushBackWaypoint(wpt);
// limit climbout speed to 240kts below 10000'
double vClimbBelow10000 = std::min(240.0, ac->getPerformance()->vClimb());
// create two climb-out points. This is important becuase the first climb point will
// be a (sometimes large) turn towards the destination, and we don't want to
// commence that turn below 2000'
double climbOut = d + pitchDistance(INITIAL_PITCH_ANGLE, 2000 * SG_FEET_TO_METER);
accelPoint = rwy->pointOnCenterline(climbOut);
wpt = createInAir(ac, "2000'", accelPoint, airportElev + 2000, vClimbBelow10000);
pushBackWaypoint(wpt);
climbOut = d + pitchDistance(INITIAL_PITCH_ANGLE, 2500 * SG_FEET_TO_METER);
accelPoint = rwy->pointOnCenterline(climbOut);
wpt = createInAir(ac, "2500'", accelPoint, airportElev + 2500, vClimbBelow10000);
pushBackWaypoint(wpt);
return true;
}
/*******************************************************************
* CreateClimb
* initialize the Aircraft at the parking location
******************************************************************/
bool FGAIFlightPlan::createClimb(FGAIAircraft * ac, bool firstFlight,
FGAirport * apt, FGAirport* arrival,
double speed, double alt,
const string & fltType)
{
FGAIWaypoint *wpt;
// string fPLName;
double vClimb = ac->getPerformance()->vClimb();
if (firstFlight) {
const string& rwyClass = getRunwayClassFromTrafficType(fltType);
double heading = ac->getTrafficRef()->getCourse();
apt->getDynamics()->getActiveRunway(rwyClass, 1, activeRunway,
heading);
}
if (sid) {
for (wpt_vector_iterator i = sid->getFirstWayPoint();
i != sid->getLastWayPoint(); i++) {
pushBackWaypoint(clone(*(i)));
//cerr << " Cloning waypoint " << endl;
}
} else {
FGRunway* runway = apt->getRunwayByIdent(activeRunway);
SGGeod cur = runway->end();
if (!waypoints.empty()) {
cur = waypoints.back()->getPos();
}
// compute course towards destination
double course = SGGeodesy::courseDeg(cur, arrival->geod());
SGGeod climb1 = SGGeodesy::direct(cur, course, 10 * SG_NM_TO_METER);
wpt = createInAir(ac, "10000ft climb", climb1, 10000, vClimb);
wpt->setGear_down(true);
wpt->setFlaps_down(true);
pushBackWaypoint(wpt);
SGGeod climb2 = SGGeodesy::direct(cur, course, 20 * SG_NM_TO_METER);
wpt = createInAir(ac, "18000ft climb", climb2, 18000, vClimb);
pushBackWaypoint(wpt);
}
return true;
}
/*******************************************************************
* CreateDescent
* Generate a flight path from the last waypoint of the cruise to
* the permission to land point
******************************************************************/
bool FGAIFlightPlan::createDescent(FGAIAircraft * ac, FGAirport * apt,
double latitude, double longitude,
double speed, double alt,
const string & fltType,
double requiredDistance)
{
bool reposition = false;
FGAIWaypoint *wpt;
double vDescent = ac->getPerformance()->vDescent();
double vApproach = ac->getPerformance()->vApproach();
//Beginning of Descent
const string& rwyClass = getRunwayClassFromTrafficType(fltType);
double heading = ac->getTrafficRef()->getCourse();
apt->getDynamics()->getActiveRunway(rwyClass, 2, activeRunway,
heading);
FGRunway * rwy = apt->getRunwayByIdent(activeRunway);
assert( rwy != NULL );
// Create a slow descent path that ends 250 lateral to the runway.
double initialTurnRadius = getTurnRadius(vDescent, true);
//double finalTurnRadius = getTurnRadius(vApproach, true);
// get length of the downwind leg for the intended runway
double distanceOut = apt->getDynamics()->getApproachController()->getRunway(rwy->name())->getApproachDistance(); //12 * SG_NM_TO_METER;
//time_t previousArrivalTime= apt->getDynamics()->getApproachController()->getRunway(rwy->name())->getEstApproachTime();
SGGeod current = SGGeod::fromDegM(longitude, latitude, 0);
SGGeod initialTarget = rwy->pointOnCenterline(-distanceOut);
SGGeod refPoint = rwy->pointOnCenterline(0);
double distance = SGGeodesy::distanceM(current, initialTarget);
double azimuth = SGGeodesy::courseDeg(current, initialTarget);
double dummyAz2;
// To prevent absurdly steep approaches, compute the origin from where the approach should have started
SGGeod origin;
if (ac->getTrafficRef()->getCallSign() ==
fgGetString("/ai/track-callsign")) {
//cerr << "Reposition information: Actual distance " << distance << ". required distance " << requiredDistance << endl;
//exit(1);
}
if (distance < requiredDistance * 0.8) {
reposition = true;
SGGeodesy::direct(initialTarget, azimuth,
-requiredDistance, origin, dummyAz2);
distance = SGGeodesy::distanceM(current, initialTarget);
azimuth = SGGeodesy::courseDeg(current, initialTarget);
} else {
origin = current;
}
double dAlt = 0; // = alt - (apt->getElevation() + 2000);
FGTaxiNode * tn = 0;
if (apt->getDynamics()->getGroundNetwork()) {
int node = apt->getDynamics()->getGroundNetwork()->findNearestNode(refPoint);
tn = apt->getDynamics()->getGroundNetwork()->findNode(node);
}
if (tn) {
dAlt = alt - ((tn->getElevationFt()) + 2000);
} else {
dAlt = alt - (apt->getElevation() + 2000);
}
double nPoints = 100;
char buffer[16];
// The descent path contains the following phases:
// 1) a linear glide path from the initial position to
// 2) a semi circle turn to final
// 3) approach
//cerr << "Phase 1: Linear Descent path to runway" << rwy->name() << endl;
// Create an initial destination point on a semicircle
//cerr << "lateral offset : " << lateralOffset << endl;
//cerr << "Distance : " << distance << endl;
//cerr << "Azimuth : " << azimuth << endl;
//cerr << "Initial Lateral point: " << lateralOffset << endl;
// double lat = refPoint.getLatitudeDeg();
// double lon = refPoint.getLongitudeDeg();
//cerr << "Reference point (" << lat << ", " << lon << ")." << endl;
// lat = initialTarget.getLatitudeDeg();
// lon = initialTarget.getLongitudeDeg();
//cerr << "Initial Target point (" << lat << ", " << lon << ")." << endl;
double ratio = initialTurnRadius / distance;
if (ratio > 1.0)
ratio = 1.0;
if (ratio < -1.0)
ratio = -1.0;
double newHeading = asin(ratio) * SG_RADIANS_TO_DEGREES;
double newDistance =
cos(newHeading * SG_DEGREES_TO_RADIANS) * distance;
//cerr << "new distance " << newDistance << ". additional Heading " << newHeading << endl;
double side = azimuth - rwy->headingDeg();
double lateralOffset = initialTurnRadius;
if (side < 0)
side += 360;
if (side < 180) {
lateralOffset *= -1;
}
// Calculate the ETA at final, based on remaining distance, and approach speed.
// distance should really consist of flying time to terniary target, plus circle
// but the distance to secondary target should work as a reasonable approximation
// aditionally add the amount of distance covered by making a turn of "side"
double turnDistance = (2 * M_PI * initialTurnRadius) * (side / 360.0);
time_t remaining =
(turnDistance + distance) / ((vDescent * SG_NM_TO_METER) / 3600.0);
time_t now = time(NULL) + fgGetLong("/sim/time/warp");
//if (ac->getTrafficRef()->getCallSign() == fgGetString("/ai/track-callsign")) {
// cerr << " Arrival time estimation: turn angle " << side << ". Turn distance " << turnDistance << ". Linear distance " << distance << ". Time to go " << remaining << endl;
// //exit(1);
//}
time_t eta = now + remaining;
//choose a distance to the runway such that it will take at least 60 seconds more
// time to get there than the previous aircraft.
// Don't bother when aircraft need to be repositioned, because that marks the initialization phased...
time_t newEta;
if (reposition == false) {
newEta =
apt->getDynamics()->getApproachController()->getRunway(rwy->
name
())->
requestTimeSlot(eta);
} else {
newEta = eta;
}
//if ((eta < (previousArrivalTime+60)) && (reposition == false)) {
arrivalTime = newEta;
time_t additionalTimeNeeded = newEta - eta;
double distanceCovered =
((vApproach * SG_NM_TO_METER) / 3600.0) * additionalTimeNeeded;
distanceOut += distanceCovered;
//apt->getDynamics()->getApproachController()->getRunway(rwy->name())->setEstApproachTime(eta+additionalTimeNeeded);
//cerr << "Adding additional distance: " << distanceCovered << " to allow " << additionalTimeNeeded << " seconds of flying time" << endl << endl;
//} else {
//apt->getDynamics()->getApproachController()->getRunway(rwy->name())->setEstApproachTime(eta);
//}
//cerr << "Timing information : Previous eta: " << previousArrivalTime << ". Current ETA : " << eta << endl;
SGGeod secondaryTarget =
rwy->pointOffCenterline(-distanceOut, lateralOffset);
initialTarget = rwy->pointOnCenterline(-distanceOut);
distance = SGGeodesy::distanceM(origin, secondaryTarget);
azimuth = SGGeodesy::courseDeg(origin, secondaryTarget);
// lat = secondaryTarget.getLatitudeDeg();
// lon = secondaryTarget.getLongitudeDeg();
//cerr << "Secondary Target point (" << lat << ", " << lon << ")." << endl;
//cerr << "Distance : " << distance << endl;
//cerr << "Azimuth : " << azimuth << endl;
ratio = initialTurnRadius / distance;
if (ratio > 1.0)
ratio = 1.0;
if (ratio < -1.0)
ratio = -1.0;
newHeading = asin(ratio) * SG_RADIANS_TO_DEGREES;
newDistance = cos(newHeading * SG_DEGREES_TO_RADIANS) * distance;
//cerr << "new distance realative to secondary target: " << newDistance << ". additional Heading " << newHeading << endl;
if (side < 180) {
azimuth += newHeading;
} else {
azimuth -= newHeading;
}
SGGeod tertiaryTarget;
SGGeodesy::direct(origin, azimuth,
newDistance, tertiaryTarget, dummyAz2);
// lat = tertiaryTarget.getLatitudeDeg();
// lon = tertiaryTarget.getLongitudeDeg();
//cerr << "tertiary Target point (" << lat << ", " << lon << ")." << endl;
for (int i = 1; i < nPoints; i++) {
SGGeod result;
double currentDist = i * (newDistance / nPoints);
double currentAltitude = alt - (i * (dAlt / nPoints));
SGGeodesy::direct(origin, azimuth, currentDist, result, dummyAz2);
snprintf(buffer, 16, "descent%03d", i);
wpt = createInAir(ac, buffer, result, currentAltitude, vDescent);
wpt->setCrossat(currentAltitude);
wpt->setTrackLength((newDistance / nPoints));
pushBackWaypoint(wpt);
//cerr << "Track Length : " << wpt->trackLength;
//cerr << " Position : " << result.getLatitudeDeg() << " " << result.getLongitudeDeg() << " " << currentAltitude << endl;
}
//cerr << "Phase 2: Circle " << endl;
double initialAzimuth =
SGGeodesy::courseDeg(secondaryTarget, tertiaryTarget);
double finalAzimuth =
SGGeodesy::courseDeg(secondaryTarget, initialTarget);
//cerr << "Angles from secondary target: " << initialAzimuth << " " << finalAzimuth << endl;
int increment, startval, endval;
// circle right around secondary target if orig of position is to the right of the runway
// i.e. use negative angles; else circle leftward and use postivi
if (side < 180) {
increment = -1;
startval = floor(initialAzimuth);
endval = ceil(finalAzimuth);
if (endval > startval) {
endval -= 360;
}
} else {
increment = 1;
startval = ceil(initialAzimuth);
endval = floor(finalAzimuth);
if (endval < startval) {
endval += 360;
}
}
//cerr << "creating circle between " << startval << " and " << endval << " using " << increment << endl;
//FGTaxiNode * tn = apt->getDynamics()->getGroundNetwork()->findNearestNode(initialTarget);
double currentAltitude = 0;
if (tn) {
currentAltitude = (tn->getElevationFt()) + 2000;
} else {
currentAltitude = apt->getElevation() + 2000;
}
double trackLength = (2 * M_PI * initialTurnRadius) / 360.0;
for (int i = startval; i != endval; i += increment) {
SGGeod result;
//double currentAltitude = apt->getElevation() + 2000;
SGGeodesy::direct(secondaryTarget, i,
initialTurnRadius, result, dummyAz2);
snprintf(buffer, 16, "turn%03d", i);
wpt = createInAir(ac, buffer, result, currentAltitude, vDescent);
wpt->setCrossat(currentAltitude);
wpt->setTrackLength(trackLength);
//cerr << "Track Length : " << wpt->trackLength;
pushBackWaypoint(wpt);
//cerr << " Position : " << result.getLatitudeDeg() << " " << result.getLongitudeDeg() << " " << currentAltitude << endl;
}
// The approach leg should bring the aircraft to approximately 4-6 nm out, after which the landing phase should take over.
//cerr << "Phase 3: Approach" << endl;
//cerr << "Done" << endl;
// Erase the two bogus BOD points: Note check for conflicts with scripted AI flightPlans
IncrementWaypoint(true);
IncrementWaypoint(true);
if (reposition) {
double tempDistance;
//double minDistance = HUGE_VAL;
//string wptName;
tempDistance = SGGeodesy::distanceM(current, initialTarget);
time_t eta =
tempDistance / ((vDescent * SG_NM_TO_METER) / 3600.0) + now;
time_t newEta =
apt->getDynamics()->getApproachController()->getRunway(rwy->
name
())->
requestTimeSlot(eta);
arrivalTime = newEta;
double newDistance =
((vDescent * SG_NM_TO_METER) / 3600.0) * (newEta - now);
//cerr << "Repositioning information : eta" << eta << ". New ETA " << newEta << ". Diff = " << (newEta - eta) << ". Distance = " << tempDistance << ". New distance = " << newDistance << endl;
IncrementWaypoint(true); // remove waypoint BOD2
while (checkTrackLength("final001") > newDistance) {
IncrementWaypoint(true);
}
//cerr << "Repositioning to waypoint " << (*waypoints.begin())->name << endl;
ac->resetPositionFromFlightPlan();
}
waypoints[1]->setName( (waypoints[1]->getName() + string("legend")));
return true;
}
/**
* compute the distance along the centerline, to the ILS glideslope
* transmitter. Return -1 if there's no GS for the runway
*/
static double runwayGlideslopeTouchdownDistance(FGRunway* rwy)
{
FGNavRecord* gs = rwy->glideslope();
if (!gs) {
return -1;
}
SGVec3d runwayPosCart = SGVec3d::fromGeod(rwy->pointOnCenterline(0.0));
// compute a unit vector in ECF cartesian space, from the runway beginning to the end
SGVec3d runwayDirectionVec = normalize(SGVec3d::fromGeod(rwy->end()) - runwayPosCart);
SGVec3d gsTransmitterVec = gs->cart() - runwayPosCart;
// project the gsTransmitterVec along the runwayDirctionVec to get out
// final value (in metres)
double dist = dot(runwayDirectionVec, gsTransmitterVec);
return dist;
}
/*******************************************************************
* CreateLanding
* Create a flight path from the "permision to land" point (currently
hardcoded at 5000 meters from the threshold) to the threshold, at
a standard glide slope angle of 3 degrees.
Position : 50.0354 8.52592 384 364 11112
******************************************************************/
bool FGAIFlightPlan::createLanding(FGAIAircraft * ac, FGAirport * apt,
const string & fltType)
{
double vTouchdown = ac->getPerformance()->vTouchdown();
double vTaxi = ac->getPerformance()->vTaxi();
double decel = ac->getPerformance()->decelerationOnGround();
double vApproach = ac->getPerformance()->vApproach();
double vTouchdownMetric = vTouchdown * SG_KT_TO_MPS;
double vTaxiMetric = vTaxi * SG_KT_TO_MPS;
double decelMetric = decel * SG_KT_TO_MPS;
char buffer[12];
FGRunway * rwy = apt->getRunwayByIdent(activeRunway);
assert( rwy != NULL );
SGGeod threshold = rwy->threshold();
double currElev = threshold.getElevationFt();
double touchdownDistance = runwayGlideslopeTouchdownDistance(rwy);
if (touchdownDistance < 0.0) {
double landingLength = rwy->lengthM() - (rwy->displacedThresholdM());
// touchdown 25% of the way along the landing area
touchdownDistance = rwy->displacedThresholdM() + (landingLength * 0.25);
}
SGGeod coord;
// find glideslope entry point, 2000' above touchdown elevation
double glideslopeEntry = -((2000 * SG_FEET_TO_METER) / tan(3.0)) + touchdownDistance;
FGAIWaypoint *wpt = createInAir(ac, "Glideslope begin", rwy->pointOnCenterline(glideslopeEntry),
currElev + 2000, vApproach);
pushBackWaypoint(wpt);
// deceleration point, 500' above touchdown elevation - slow from approach speed
// to touchdown speed
double decelPoint = -((500 * SG_FEET_TO_METER) / tan(3.0)) + touchdownDistance;
wpt = createInAir(ac, "500' decel", rwy->pointOnCenterline(decelPoint),
currElev + 2000, vTouchdown);
pushBackWaypoint(wpt);
// compute elevation above the runway start, based on a 3-degree glideslope
double heightAboveRunwayStart = touchdownDistance *
tan(3.0 * SG_DEGREES_TO_RADIANS) * SG_METER_TO_FEET;
wpt = createInAir(ac, "CrossThreshold", rwy->begin(),
heightAboveRunwayStart + currElev, vTouchdown);
pushBackWaypoint(wpt);
double rolloutDistance = accelDistance(vTouchdownMetric, vTaxiMetric, decelMetric);
int nPoints = 50;
for (int i = 1; i < nPoints; i++) {
snprintf(buffer, 12, "landing03%d", i);
double t = ((double) i) / nPoints;
coord = rwy->pointOnCenterline(touchdownDistance + (rolloutDistance * t));
double vel = (vTouchdownMetric * (1.0 - t)) + (vTaxiMetric * t);
wpt = createOnGround(ac, buffer, coord, currElev, vel);
wpt->setCrossat(currElev);
pushBackWaypoint(wpt);
}
wpt->setSpeed(vTaxi);
double mindist = (1.1 * rolloutDistance) + touchdownDistance;
FGGroundNetwork *gn = apt->getDynamics()->getGroundNetwork();
if (!gn) {
return true;
}
coord = rwy->pointOnCenterline(mindist);
int nodeId = 0;
if (gn->getVersion() > 0) {
nodeId = gn->findNearestNodeOnRunway(coord, rwy);
} else {
nodeId = gn->findNearestNode(coord);
}
FGTaxiNode* tn = gn->findNode(nodeId);
if (tn) {
wpt = createOnGround(ac, buffer, tn->geod(), currElev, vTaxi);
pushBackWaypoint(wpt);
}
return true;
}
/*******************************************************************
* CreateParking
* initialize the Aircraft at the parking location
******************************************************************/
bool FGAIFlightPlan::createParking(FGAIAircraft * ac, FGAirport * apt,
double radius)
{
FGAIWaypoint *wpt;
double aptElev = apt->getElevation();
double vTaxi = ac->getPerformance()->vTaxi();
double vTaxiReduced = vTaxi * (2.0 / 3.0);
if (!gate.isValid()) {
wpt = createOnGround(ac, "END-Parking", apt->geod(), aptElev,
vTaxiReduced);
pushBackWaypoint(wpt);
return true;
}
FGParking* parking = gate.parking();
double heading = SGMiscd::normalizePeriodic(0, 360, parking->getHeading() + 180.0);
double az; // unused
SGGeod pos;
SGGeodesy::direct(parking->geod(), heading, 2.2 * parking->getRadius(),
pos, az);
wpt = createOnGround(ac, "taxiStart", pos, aptElev, vTaxiReduced);
pushBackWaypoint(wpt);
SGGeodesy::direct(parking->geod(), heading, 0.1 * parking->getRadius(),
pos, az);
wpt = createOnGround(ac, "taxiStart2", pos, aptElev, vTaxiReduced);
pushBackWaypoint(wpt);
wpt = createOnGround(ac, "END-Parking", parking->geod(), aptElev,
vTaxiReduced);
pushBackWaypoint(wpt);
return true;
}
/**
*
* @param fltType a string describing the type of
* traffic, normally used for gate assignments
* @return a converted string that gives the runway
* preference schedule to be used at aircraft having
* a preferential runway schedule implemented (i.e.
* having a rwyprefs.xml file
*
* Currently valid traffic types for gate assignment:
* - gate (commercial gate)
* - cargo (commercial gargo),
* - ga (general aviation) ,
* - ul (ultralight),
* - mil-fighter (military - fighter),
* - mil-transport (military - transport)
*
* Valid runway classes:
* - com (commercial traffic: jetliners, passenger and cargo)
* - gen (general aviation)
* - ul (ultralight: I can imagine that these may share a runway with ga on some airports)
* - mil (all military traffic)
*/
const char* FGAIFlightPlan::getRunwayClassFromTrafficType(const string& fltType)
{
if ((fltType == "gate") || (fltType == "cargo")) {
return "com";
}
if (fltType == "ga") {
return "gen";
}
if (fltType == "ul") {
return "ul";
}
if ((fltType == "mil-fighter") || (fltType == "mil-transport")) {
return "mil";
}
return "com";
}
double FGAIFlightPlan::getTurnRadius(double speed, bool inAir)
{
double turn_radius;
if (inAir == false) {
turn_radius = ((360 / 30) * fabs(speed)) / (2 * M_PI);
} else {
turn_radius = 0.1911 * speed * speed; // an estimate for 25 degrees bank
}
return turn_radius;
}