src/FDM/YASim/FGFDM.cpp

   1 #ifdef HAVE_CONFIG_H
   2 #  include "config.h"
   3 #endif
   4
   5 #include <stdio.h>
   6 #include <stdlib.h>
   7
   8 #include <Main/fg_props.hxx>
   9
  10 #include "Math.hpp"
  11 #include "Jet.hpp"
  12 #include "SimpleJet.hpp"
  13 #include "Gear.hpp"
  14 #include "Hook.hpp"
  15 #include "Launchbar.hpp"
  16 #include "Atmosphere.hpp"
  17 #include "PropEngine.hpp"
  18 #include "Propeller.hpp"
  19 #include "PistonEngine.hpp"
  20 #include "TurbineEngine.hpp"
  21 #include "Rotor.hpp"
  22 #include "Rotorpart.hpp"
  23 #include "Hitch.hpp"
  24
  25 #include "FGFDM.hpp"
  26
  27 namespace yasim {
  28
  29 // Some conversion factors
  30 static const float KTS2MPS = 0.514444444444;
  31 static const float FT2M = 0.3048;
  32 static const float DEG2RAD = 0.0174532925199;
  33 static const float RPM2RAD = 0.10471975512;
  34 static const float LBS2N = 4.44822;
  35 static const float LBS2KG = 0.45359237;
  36 static const float KG2LBS = 2.2046225;
  37 static const float CM2GALS = 264.172037284;
  38 static const float HP2W = 745.700;
  39 static const float INHG2PA = 3386.389;
  40 static const float K2DEGF = 1.8;
  41 static const float K2DEGFOFFSET = -459.4;
  42 static const float CIN2CM = 1.6387064e-5;
  43 static const float YASIM_PI = 3.14159265358979323846;
  44
  45 static const float NM2FTLB = (1/(LBS2N*FT2M));
  46
  47 // Stubs, so that this can be compiled without the FlightGear
  48 // binary.  What's the best way to handle this?
  49
  50 //     float fgGetFloat(char* name, float def) { return 0; }
  51 //     void fgSetFloat(char* name, float val) {}
  52
  53 FGFDM::FGFDM()
  54 {
  55     _vehicle_radius = 0.0f;
  56
  57     _nextEngine = 0;
  58
  59     // Map /controls/flight/elevator to the approach elevator control.  This
  60     // should probably be settable, but there are very few aircraft
  61     // who trim their approaches using things other than elevator.
  62     _airplane.setElevatorControl(parseAxis("/controls/flight/elevator-trim"));
  63
  64     // FIXME: read seed from somewhere?
  65     int seed = 0;
  66     _turb = new Turbulence(10, seed);
  67 }
  68
  69 FGFDM::~FGFDM()
  70 {
  71     for(int i=0; i<_axes.size(); i++) {
  72         AxisRec* a = (AxisRec*)_axes.get(i);
  73         delete[] a->name;
  74         delete a;
  75     }
  76
  77     for(int i=0; i<_thrusters.size(); i++) {
  78         EngRec* er = (EngRec*)_thrusters.get(i);
  79         delete[] er->prefix;
  80         delete er->eng;
  81         delete er;
  82     }
  83
  84     for(int i=0; i<_weights.size(); i++) {
  85         WeightRec* wr = (WeightRec*)_weights.get(i);
  86         delete[] wr->prop;
  87         delete wr;
  88     }
  89
  90     for(int i=0; i<_controlProps.size(); i++)
  91         delete (PropOut*)_controlProps.get(i);
  92
  93     delete _turb;
  94 }
  95
  96 void FGFDM::iterate(float dt)
  97 {
  98     getExternalInput(dt);
  99     _airplane.iterate(dt);
 100
 101     // Do fuel stuff
 102     for(int i=0; i<_airplane.numThrusters(); i++) {
 103         Thruster* t = _airplane.getThruster(i);
 104
 105         bool out_of_fuel = _fuel_props[i]._out_of_fuel->getBoolValue();
 106         t->setFuelState(!out_of_fuel);
 107
 108         double consumed = _fuel_props[i]._fuel_consumed_lbs->getDoubleValue();
 109         _fuel_props[i]._fuel_consumed_lbs->setDoubleValue(
 110                 consumed + dt * KG2LBS * t->getFuelFlow());
 111     }
 112     for(int i=0; i<_airplane.numTanks(); i++) {
 113         _airplane.setFuel(i, LBS2KG * _tank_level_lbs[i]->getFloatValue());
 114     }
 115     _airplane.calcFuelWeights();
 116
 117     setOutputProperties(dt);
 118 }
 119
 120 Airplane* FGFDM::getAirplane()
 121 {
 122     return &_airplane;
 123 }
 124
 125 void FGFDM::init()
 126 {
 127     _turb_magnitude_norm = fgGetNode("/environment/turbulence/magnitude-norm", true);
 128     _turb_rate_hz        = fgGetNode("/environment/turbulence/rate-hz", true);
 129     _gross_weight_lbs    = fgGetNode("/yasim/gross-weight-lbs", true);
 130
 131     // Allows the user to start with something other than full fuel
 132     _airplane.setFuelFraction(fgGetFloat("/sim/fuel-fraction", 1));
 133
 134     // stash engine/thruster properties
 135     _thrust_props.clear();
 136     for (int i=0; i<_thrusters.size(); i++) {
 137         SGPropertyNode_ptr node = fgGetNode("engines/engine", i, true);
 138         Thruster* t = ((EngRec*)_thrusters.get(i))->eng;
 139
 140         ThrusterProps tp;
 141         tp._running =       node->getChild("running", 0, true);
 142         tp._cranking =      node->getChild("cranking", 0, true);
 143         tp._prop_thrust =   node->getChild("prop-thrust", 0, true); // Deprecated name
 144         tp._thrust_lbs =    node->getChild("thrust-lbs", 0, true);
 145         tp._fuel_flow_gph = node->getChild("fuel-flow-gph", 0, true);
 146
 147         if(t->getPropEngine())
 148         {
 149             tp._rpm = node->getChild("rpm", 0, true);
 150             tp._torque_ftlb = node->getChild("torque-ftlb", 0, true);
 151
 152             PropEngine* p = t->getPropEngine();
 153             if(p->getEngine()->isPistonEngine())
 154             {
 155                 tp._mp_osi =   node->getChild("mp-osi",   0, true);
 156                 tp._mp_inhg =  node->getChild("mp-inhg",  0, true);
 157                 tp._egt_degf = node->getChild("egt-degf", 0, true);
 158
 159                 tp._oil_temperature_degf = node->getChild("oil-temperature-degf", 0, true);
 160                 tp._boost_gauge_inhg =     node->getChild("boost-gauge-inhg", 0, true);
 161             } else if(p->getEngine()->isTurbineEngine()) {
 162                 tp._n2 = node->getChild("n2", 0, true);
 163             }
 164         }
 165
 166         if(t->getJet())
 167         {
 168             tp._n1 =       node->getChild("n1",       0, true);
 169             tp._n2 =       node->getChild("n2",       0, true);
 170             tp._epr =      node->getChild("epr",      0, true);
 171             tp._egt_degf = node->getChild("egt-degf", 0, true);
 172         }
 173         _thrust_props.push_back(tp);
 174     }
 175
 176     // stash properties for fuel state
 177     _fuel_props.clear();
 178     for(int i=0; i<_airplane.numThrusters(); i++) {
 179         SGPropertyNode_ptr e = fgGetNode("engines/engine", i, true);
 180         FuelProps f;
 181         f._out_of_fuel       = e->getChild("out-of-fuel", 0, true);
 182         f._fuel_consumed_lbs = e->getChild("fuel-consumed-lbs", 0, true);
 183         _fuel_props.push_back(f);
 184     }
 185
 186     // initialize tanks and stash properties for tank level
 187     _tank_level_lbs.clear();
 188     for(int i=0; i<_airplane.numTanks(); i++) {
 189         char buf[256];
 190         sprintf(buf, "/consumables/fuel/tank[%d]/level-lbs", i);
 191         fgSetDouble(buf, _airplane.getFuel(i) * KG2LBS);
 192         _tank_level_lbs.push_back(fgGetNode(buf, true));
 193
 194         double density = _airplane.getFuelDensity(i);
 195         sprintf(buf, "/consumables/fuel/tank[%d]/density-ppg", i);
 196         fgSetDouble(buf, density * (KG2LBS/CM2GALS));
 197
 198 // set in TankProperties class
 199 //        sprintf(buf, "/consumables/fuel/tank[%d]/level-gal_us", i);
 200 //        fgSetDouble(buf, _airplane.getFuel(i) * CM2GALS / density);
 201
 202         sprintf(buf, "/consumables/fuel/tank[%d]/capacity-gal_us", i);
 203         fgSetDouble(buf, CM2GALS * _airplane.getTankCapacity(i)/density);
 204     }
 205
 206     // This has a nasty habit of being false at startup.  That's not
 207     // good.
 208     fgSetBool("/controls/gear/gear-down", true);
 209
 210     _airplane.getModel()->setTurbulence(_turb);
 211 }
 212
 213 // Not the worlds safest parser.  But it's short & sweet.
 214 void FGFDM::startElement(const char* name, const XMLAttributes &atts)
 215 {
 216     XMLAttributes* a = (XMLAttributes*)&atts;
 217     float v[3];
 218     char buf[64];
 219
 220     if(eq(name, "airplane")) {
 221         _airplane.setWeight(attrf(a, "mass") * LBS2KG);
 222         if(a->hasAttribute("version")) {
 223           _airplane.setVersion( a->getValue("version") );
 224         }
 225         if( !_airplane.isVersionOrNewer( Version::YASIM_VERSION_CURRENT ) ) {
 226           SG_LOG(SG_FLIGHT,SG_ALERT, "This aircraft does not use the latest yasim configuration version.");
 227         }
 228     } else if(eq(name, "approach")) {
 229         float spd = attrf(a, "speed") * KTS2MPS;
 230         float alt = attrf(a, "alt", 0) * FT2M;
 231         float aoa = attrf(a, "aoa", 0) * DEG2RAD;
 232         float gla = attrf(a, "glide-angle", 0) * DEG2RAD;
 233         _airplane.setApproach(spd, alt, aoa, attrf(a, "fuel", 0.2),gla);
 234         _cruiseCurr = false;
 235     } else if(eq(name, "cruise")) {
 236         float spd = attrf(a, "speed") * KTS2MPS;
 237         float alt = attrf(a, "alt") * FT2M;
 238         float gla = attrf(a, "glide-angle", 0) * DEG2RAD;
 239         _airplane.setCruise(spd, alt, attrf(a, "fuel", 0.5),gla);
 240         _cruiseCurr = true;
 241     } else if(eq(name, "solve-weight")) {
 242         int idx = attri(a, "idx");
 243         float wgt = attrf(a, "weight") * LBS2KG;
 244         _airplane.addSolutionWeight(!_cruiseCurr, idx, wgt);
 245     } else if(eq(name, "cockpit")) {
 246         v[0] = attrf(a, "x");
 247         v[1] = attrf(a, "y");
 248         v[2] = attrf(a, "z");
 249         _airplane.setPilotPos(v);
 250     } else if(eq(name, "rotor")) {
 251         _airplane.getModel()->getRotorgear()->addRotor(parseRotor(a, name));
 252     } else if(eq(name, "rotorgear")) {
 253         Rotorgear* r = _airplane.getModel()->getRotorgear();
 254         _currObj = r;
 255         #define p(x) if (a->hasAttribute(#x)) r->setParameter((char *)#x,attrf(a,#x) );
 256         #define p2(x,y) if (a->hasAttribute(y)) r->setParameter((char *)#x,attrf(a,y) );
 257         p2(max_power_engine,"max-power-engine")
 258         p2(engine_prop_factor,"engine-prop-factor")
 259         p(yasimdragfactor)
 260         p(yasimliftfactor)
 261         p2(max_power_rotor_brake,"max-power-rotor-brake")
 262         p2(rotorgear_friction,"rotorgear-friction")
 263         p2(engine_accel_limit,"engine-accel-limit")
 264         #undef p
 265         #undef p2
 266         r->setInUse();
 267     } else if(eq(name, "wing")) {
 268         _airplane.setWing(parseWing(a, name, &_airplane));
 269     } else if(eq(name, "hstab")) {
 270         _airplane.setTail(parseWing(a, name, &_airplane));
 271     } else if(eq(name, "vstab") || eq(name, "mstab")) {
 272         _airplane.addVStab(parseWing(a, name, &_airplane));
 273     } else if(eq(name, "piston-engine")) {
 274         parsePistonEngine(a);
 275     } else if(eq(name, "turbine-engine")) {
 276         parseTurbineEngine(a);
 277     } else if(eq(name, "propeller")) {
 278         parsePropeller(a);
 279     } else if(eq(name, "thruster")) {
 280         SimpleJet* j = new SimpleJet();
 281         _currObj = j;
 282         v[0] = attrf(a, "x"); v[1] = attrf(a, "y"); v[2] = attrf(a, "z");
 283         j->setPosition(v);
 284         _airplane.addThruster(j, 0, v);
 285         v[0] = attrf(a, "vx"); v[1] = attrf(a, "vy"); v[2] = attrf(a, "vz");
 286         j->setDirection(v);
 287         j->setThrust(attrf(a, "thrust") * LBS2N);
 288     } else if(eq(name, "jet")) {
 289         Jet* j = new Jet();
 290         _currObj = j;
 291         v[0] = attrf(a, "x");
 292         v[1] = attrf(a, "y");
 293         v[2] = attrf(a, "z");
 294         float mass = attrf(a, "mass") * LBS2KG;
 295         j->setMaxThrust(attrf(a, "thrust") * LBS2N,
 296                         attrf(a, "afterburner", 0) * LBS2N);
 297         j->setVectorAngle(attrf(a, "rotate", 0) * DEG2RAD);
 298         j->setReverseThrust(attrf(a, "reverse", 0.2));
 299
 300         float n1min = attrf(a, "n1-idle", 55);
 301         float n1max = attrf(a, "n1-max", 102);
 302         float n2min = attrf(a, "n2-idle", 73);
 303         float n2max = attrf(a, "n2-max", 103);
 304         j->setRPMs(n1min, n1max, n2min, n2max);
 305
 306         j->setTSFC(attrf(a, "tsfc", 0.8));
 307         if(a->hasAttribute("egt"))  j->setEGT(attrf(a, "egt"));
 308         if(a->hasAttribute("epr"))  j->setEPR(attrf(a, "epr"));
 309         if(a->hasAttribute("exhaust-speed"))
 310             j->setVMax(attrf(a, "exhaust-speed") * KTS2MPS);
 311         if(a->hasAttribute("spool-time"))
 312             j->setSpooling(attrf(a, "spool-time"));
 313
 314         j->setPosition(v);
 315         _airplane.addThruster(j, mass, v);
 316         sprintf(buf, "/engines/engine[%d]", _nextEngine++);
 317         EngRec* er = new EngRec();
 318         er->eng = j;
 319         er->prefix = dup(buf);
 320         _thrusters.add(er);
 321     } else if(eq(name, "hitch")) {
 322         Hitch* h = new Hitch(a->getValue("name"));
 323         _currObj = h;
 324         v[0] = attrf(a, "x");
 325         v[1] = attrf(a, "y");
 326         v[2] = attrf(a, "z");
 327         h->setPosition(v);
 328         if(a->hasAttribute("force-is-calculated-by-other")) h->setForceIsCalculatedByOther(attrb(a,"force-is-calculated-by-other"));
 329         _airplane.addHitch(h);
 330     } else if(eq(name, "tow")) {
 331         Hitch* h = (Hitch*)_currObj;
 332         if(a->hasAttribute("length"))
 333             h->setTowLength(attrf(a, "length"));
 334         if(a->hasAttribute("elastic-constant"))
 335             h->setTowElasticConstant(attrf(a, "elastic-constant"));
 336         if(a->hasAttribute("break-force"))
 337             h->setTowBreakForce(attrf(a, "break-force"));
 338         if(a->hasAttribute("weight-per-meter"))
 339             h->setTowWeightPerM(attrf(a, "weight-per-meter"));
 340         if(a->hasAttribute("mp-auto-connect-period"))
 341             h->setMpAutoConnectPeriod(attrf(a, "mp-auto-connect-period"));
 342     } else if(eq(name, "winch")) {
 343         Hitch* h = (Hitch*)_currObj;
 344         double pos[3];
 345         pos[0] = attrd(a, "x",0);
 346         pos[1] = attrd(a, "y",0);
 347         pos[2] = attrd(a, "z",0);
 348         h->setWinchPosition(pos);
 349         if(a->hasAttribute("max-speed"))
 350             h->setWinchMaxSpeed(attrf(a, "max-speed"));
 351         if(a->hasAttribute("power"))
 352             h->setWinchPower(attrf(a, "power") * 1000);
 353         if(a->hasAttribute("max-force"))
 354             h->setWinchMaxForce(attrf(a, "max-force"));
 355         if(a->hasAttribute("initial-tow-length"))
 356             h->setWinchInitialTowLength(attrf(a, "initial-tow-length"));
 357         if(a->hasAttribute("max-tow-length"))
 358             h->setWinchMaxTowLength(attrf(a, "max-tow-length"));
 359         if(a->hasAttribute("min-tow-length"))
 360             h->setWinchMinTowLength(attrf(a, "min-tow-length"));
 361     } else if(eq(name, "gear")) {
 362         Gear* g = new Gear();
 363         _currObj = g;
 364         v[0] = attrf(a, "x");
 365         v[1] = attrf(a, "y");
 366         v[2] = attrf(a, "z");
 367         g->setPosition(v);
 368         float nrm = Math::mag3(v);
 369         if (_vehicle_radius < nrm)
 370             _vehicle_radius = nrm;
 371         if(a->hasAttribute("upx")) {
 372             v[0] = attrf(a, "upx");
 373             v[1] = attrf(a, "upy");
 374             v[2] = attrf(a, "upz");
 375             Math::unit3(v, v);
 376         } else {
 377             v[0] = 0;
 378             v[1] = 0;
 379             v[2] = 1;
 380         }
 381         for(int i=0; i<3; i++)
 382             v[i] *= attrf(a, "compression", 1);
 383         g->setCompression(v);
 384         g->setBrake(attrf(a, "skid", 0));
 385         g->setInitialLoad(attrf(a, "initial-load", 0));
 386         g->setStaticFriction(attrf(a, "sfric", 0.8));
 387         g->setDynamicFriction(attrf(a, "dfric", 0.7));
 388         g->setSpring(attrf(a, "spring", 1));
 389         g->setDamping(attrf(a, "damp", 1));
 390         if(a->hasAttribute("on-water")) g->setOnWater(attrb(a,"on-water"));
 391         if(a->hasAttribute("on-solid")) g->setOnSolid(attrb(a,"on-solid"));
 392         if(a->hasAttribute("ignored-by-solver")) g->setIgnoreWhileSolving(attrb(a,"ignored-by-solver"));
 393         g->setSpringFactorNotPlaning(attrf(a, "spring-factor-not-planing", 1));
 394         g->setSpeedPlaning(attrf(a, "speed-planing", 0) * KTS2MPS);
 395         g->setReduceFrictionByExtension(attrf(a, "reduce-friction-by-extension", 0));
 396         _airplane.addGear(g);
 397     } else if(eq(name, "hook")) {
 398         Hook* h = new Hook();
 399         _currObj = h;
 400         v[0] = attrf(a, "x");
 401         v[1] = attrf(a, "y");
 402         v[2] = attrf(a, "z");
 403         h->setPosition(v);
 404         float length = attrf(a, "length", 1.0);
 405         h->setLength(length);
 406         float nrm = length+Math::mag3(v);
 407         if (_vehicle_radius < nrm)
 408             _vehicle_radius = nrm;
 409         h->setDownAngle(attrf(a, "down-angle", 70) * DEG2RAD);
 410         h->setUpAngle(attrf(a, "up-angle", 0) * DEG2RAD);
 411         _airplane.addHook(h);
 412     } else if(eq(name, "launchbar")) {
 413         Launchbar* l = new Launchbar();
 414         _currObj = l;
 415         v[0] = attrf(a, "x");
 416         v[1] = attrf(a, "y");
 417         v[2] = attrf(a, "z");
 418         l->setLaunchbarMount(v);
 419         v[0] = attrf(a, "holdback-x", v[0]);
 420         v[1] = attrf(a, "holdback-y", v[1]);
 421         v[2] = attrf(a, "holdback-z", v[2]);
 422         l->setHoldbackMount(v);
 423         float length = attrf(a, "length", 1.0);
 424         l->setLength(length);
 425         l->setDownAngle(attrf(a, "down-angle", 45) * DEG2RAD);
 426         l->setUpAngle(attrf(a, "up-angle", -45) * DEG2RAD);
 427         l->setHoldbackLength(attrf(a, "holdback-length", 2.0));
 428         _airplane.addLaunchbar(l);
 429     } else if(eq(name, "fuselage")) {
 430         float b[3];
 431         v[0] = attrf(a, "ax");
 432         v[1] = attrf(a, "ay");
 433         v[2] = attrf(a, "az");
 434         b[0] = attrf(a, "bx");
 435         b[1] = attrf(a, "by");
 436         b[2] = attrf(a, "bz");
 437         float taper = attrf(a, "taper", 1);
 438         float mid = attrf(a, "midpoint", 0.5);
 439         if (_airplane.isVersionOrNewer(Version::YASIM_VERSION_32)) {
 440             // A fuselage's "midpoint" XML attribute is defined from the
 441             // fuselage's front end, but the Fuselage object's internal
 442             // "mid" attribute is actually defined from the rear end.
 443             // Thus YASim's original interpretation of "midpoint" was wrong.
 444             // Complement the "midpoint" value to ensure the fuselage
 445             // points the right way.
 446             mid = 1 - mid;
 447         }
 448         float cx = attrf(a, "cx", 1);
 449         float cy = attrf(a, "cy", 1);
 450         float cz = attrf(a, "cz", 1);
 451         float idrag = attrf(a, "idrag", 1);
 452         _airplane.addFuselage(v, b, attrf(a, "width"), taper, mid,
 453             cx, cy, cz, idrag);
 454     } else if(eq(name, "tank")) {
 455         v[0] = attrf(a, "x");
 456         v[1] = attrf(a, "y");
 457         v[2] = attrf(a, "z");
 458         float density = 6.0; // gasoline, in lbs/gal
 459         if(a->hasAttribute("jet")) density = 6.72;
 460         density *= LBS2KG*CM2GALS;
 461         _airplane.addTank(v, attrf(a, "capacity") * LBS2KG, density);
 462     } else if(eq(name, "ballast")) {
 463         v[0] = attrf(a, "x");
 464         v[1] = attrf(a, "y");
 465         v[2] = attrf(a, "z");
 466         _airplane.addBallast(v, attrf(a, "mass") * LBS2KG);
 467     } else if(eq(name, "weight")) {
 468         parseWeight(a);
 469     } else if(eq(name, "stall")) {
 470         Wing* w = (Wing*)_currObj;
 471         w->setStall(attrf(a, "aoa") * DEG2RAD);
 472         w->setStallWidth(attrf(a, "width", 2) * DEG2RAD);
 473         w->setStallPeak(attrf(a, "peak", 1.5));
 474     } else if(eq(name, "flap0")) {
 475         ((Wing*)_currObj)->setFlap0(attrf(a, "start"), attrf(a, "end"),
 476                                     attrf(a, "lift"), attrf(a, "drag"));
 477     } else if(eq(name, "flap1")) {
 478         ((Wing*)_currObj)->setFlap1(attrf(a, "start"), attrf(a, "end"),
 479                                     attrf(a, "lift"), attrf(a, "drag"));
 480     } else if(eq(name, "slat")) {
 481         ((Wing*)_currObj)->setSlat(attrf(a, "start"), attrf(a, "end"),
 482                                    attrf(a, "aoa"), attrf(a, "drag"));
 483     } else if(eq(name, "spoiler")) {
 484         ((Wing*)_currObj)->setSpoiler(attrf(a, "start"), attrf(a, "end"),
 485                                       attrf(a, "lift"), attrf(a, "drag"));
 486     /* } else if(eq(name, "collective")) {
 487         ((Rotor*)_currObj)->setcollective(attrf(a, "min"), attrf(a, "max"));
 488     } else if(eq(name, "cyclic")) {
 489         ((Rotor*)_currObj)->setcyclic(attrf(a, "ail"), attrf(a, "ele"));
 490     */
 491     } else if(eq(name, "actionpt")) {
 492         v[0] = attrf(a, "x");
 493         v[1] = attrf(a, "y");
 494         v[2] = attrf(a, "z");
 495         ((Thruster*)_currObj)->setPosition(v);
 496     } else if(eq(name, "dir")) {
 497         v[0] = attrf(a, "x");
 498         v[1] = attrf(a, "y");
 499         v[2] = attrf(a, "z");
 500         ((Thruster*)_currObj)->setDirection(v);
 501     } else if(eq(name, "control-setting")) {
 502         // A cruise or approach control setting
 503         const char* axis = a->getValue("axis");
 504         float value = attrf(a, "value", 0);
 505         if(_cruiseCurr)
 506             _airplane.addCruiseControl(parseAxis(axis), value);
 507         else
 508             _airplane.addApproachControl(parseAxis(axis), value);
 509     } else if(eq(name, "control-input")) {
 510
 511         // A mapping of input property to a control
 512         int axis = parseAxis(a->getValue("axis"));
 513         int control = parseOutput(a->getValue("control"));
 514         int opt = 0;
 515         opt |= a->hasAttribute("split") ? ControlMap::OPT_SPLIT : 0;
 516         opt |= a->hasAttribute("invert") ? ControlMap::OPT_INVERT : 0;
 517         opt |= a->hasAttribute("square") ? ControlMap::OPT_SQUARE : 0;
 518
 519         ControlMap* cm = _airplane.getControlMap();
 520         if(a->hasAttribute("src0")) {
 521                            cm->addMapping(axis, control, _currObj, opt,
 522                            attrf(a, "src0"), attrf(a, "src1"),
 523                            attrf(a, "dst0"), attrf(a, "dst1"));
 524         } else {
 525             cm->addMapping(axis, control, _currObj, opt);
 526         }
 527     } else if(eq(name, "control-output")) {
 528         // A property output for a control on the current object
 529         ControlMap* cm = _airplane.getControlMap();
 530         int type = parseOutput(a->getValue("control"));
 531         int handle = cm->getOutputHandle(_currObj, type);
 532
 533         PropOut* p = new PropOut();
 534         p->prop = fgGetNode(a->getValue("prop"), true);
 535         p->handle = handle;
 536         p->type = type;
 537         p->left = !(a->hasAttribute("side") &&
 538                         eq("right", a->getValue("side")));
 539         p->min = attrf(a, "min", cm->rangeMin(type));
 540         p->max = attrf(a, "max", cm->rangeMax(type));
 541         _controlProps.add(p);
 542
 543     } else if(eq(name, "control-speed")) {
 544         ControlMap* cm = _airplane.getControlMap();
 545         int type = parseOutput(a->getValue("control"));
 546         int handle = cm->getOutputHandle(_currObj, type);
 547         float time = attrf(a, "transition-time", 0);
 548
 549         cm->setTransitionTime(handle, time);
 550     } else {
 551         SG_LOG(SG_FLIGHT,SG_ALERT,"Unexpected tag '"
 552                << name << "' found in YASim aircraft description");
 553         exit(1);
 554     }
 555 }
 556
 557 void FGFDM::getExternalInput(float dt)
 558 {
 559     char buf[256];
 560
 561     _turb->setMagnitude(_turb_magnitude_norm->getFloatValue());
 562     _turb->update(dt, _turb_rate_hz->getFloatValue());
 563
 564     // The control axes
 565     ControlMap* cm = _airplane.getControlMap();
 566     cm->reset();
 567
 568     for(int i=0; i<_axes.size(); i++) {
 569         AxisRec* a = (AxisRec*)_axes.get(i);
 570         float val = fgGetFloat(a->name, 0);
 571         cm->setInput(a->handle, val);
 572     }
 573     cm->applyControls(dt);
 574
 575     // Weights
 576     for(int i=0; i<_weights.size(); i++) {
 577         WeightRec* wr = (WeightRec*)_weights.get(i);
 578         _airplane.setWeight(wr->handle, LBS2KG * fgGetFloat(wr->prop));
 579     }
 580
 581     for(int i=0; i<_thrusters.size(); i++) {
 582         EngRec* er = (EngRec*)_thrusters.get(i);
 583         Thruster* t = er->eng;
 584
 585         if(t->getPropEngine()) {
 586             PropEngine* p = t->getPropEngine();
 587             sprintf(buf, "%s/rpm", er->prefix);
 588             p->setOmega(fgGetFloat(buf, 500) * RPM2RAD);
 589         }
 590     }
 591 }
 592
 593 // Linearly "seeks" a property by the specified fraction of the way to
 594 // the target value.  Used to emulate "slowly changing" output values.
 595 static void moveprop(SGPropertyNode* node, const char* prop,
 596                     float target, float frac)
 597 {
 598     float val = node->getFloatValue(prop);
 599     if(frac > 1) frac = 1;
 600     if(frac < 0) frac = 0;
 601     val += (target - val) * frac;
 602     node->setFloatValue(prop, val);
 603 }
 604
 605 void FGFDM::setOutputProperties(float dt)
 606 {
 607     float grossWgt = _airplane.getModel()->getBody()->getTotalMass() * KG2LBS;
 608     _gross_weight_lbs->setFloatValue(grossWgt);
 609
 610     ControlMap* cm = _airplane.getControlMap();
 611     for(int i=0; i<_controlProps.size(); i++) {
 612         PropOut* p = (PropOut*)_controlProps.get(i);
 613         float val = (p->left
 614                      ? cm->getOutput(p->handle)
 615                      : cm->getOutputR(p->handle));
 616         float rmin = cm->rangeMin(p->type);
 617         float rmax = cm->rangeMax(p->type);
 618         float frac = (val - rmin) / (rmax - rmin);
 619         val = frac*(p->max - p->min) + p->min;
 620         p->prop->setFloatValue(val);
 621     }
 622
 623     for(int i=0; i<_airplane.getRotorgear()->getNumRotors(); i++) {
 624         Rotor*r=(Rotor*)_airplane.getRotorgear()->getRotor(i);
 625         int j = 0;
 626         float f;
 627         char b[256];
 628         while((j = r->getValueforFGSet(j, b, &f)))
 629             if(b[0]) fgSetFloat(b,f);
 630         j=0;
 631         while((j = _airplane.getRotorgear()->getValueforFGSet(j, b, &f)))
 632             if(b[0]) fgSetFloat(b,f);
 633         for(j=0; j < r->numRotorparts(); j+=r->numRotorparts()>>2) {
 634             Rotorpart* s = (Rotorpart*)r->getRotorpart(j);
 635             char *b;
 636             int k;
 637             for(k=0; k<2; k++) {
 638                 b=s->getAlphaoutput(k);
 639                 if(b[0]) fgSetFloat(b, s->getAlpha(k));
 640             }
 641         }
 642     }
 643
 644     // Use the density of the first tank, or a dummy value if no tanks
 645     float fuelDensity = 1.0;
 646     if(_airplane.numTanks())
 647         fuelDensity = _airplane.getFuelDensity(0);
 648     for(int i=0; i<_thrusters.size(); i++) {
 649         EngRec* er = (EngRec*)_thrusters.get(i);
 650         Thruster* t = er->eng;
 651         SGPropertyNode * node = fgGetNode("engines/engine", i, true);
 652
 653         ThrusterProps& tp = _thrust_props[i];
 654
 655         // Set: running, cranking, prop-thrust, max-hp, power-pct
 656         tp._running->setBoolValue(t->isRunning());
 657         tp._cranking->setBoolValue(t->isCranking());
 658
 659         float tmp[3];
 660         t->getThrust(tmp);
 661         float lbs = Math::mag3(tmp) * (KG2LBS/9.8);
 662         tp._prop_thrust->setFloatValue(lbs); // Deprecated name
 663         tp._thrust_lbs->setFloatValue(lbs);
 664         tp._fuel_flow_gph->setFloatValue(
 665                 (t->getFuelFlow()/fuelDensity) * 3600 * CM2GALS);
 666
 667         if(t->getPropEngine()) {
 668             PropEngine* p = t->getPropEngine();
 669             tp._rpm->setFloatValue(p->getOmega() * (1/RPM2RAD));
 670             tp._torque_ftlb->setFloatValue(
 671                     p->getEngine()->getTorque() * NM2FTLB);
 672
 673             if(p->getEngine()->isPistonEngine()) {
 674                 PistonEngine* pe = p->getEngine()->isPistonEngine();
 675                 tp._mp_osi->setFloatValue(pe->getMP() * (1/INHG2PA));
 676                 tp._mp_inhg->setFloatValue(pe->getMP() * (1/INHG2PA));
 677                 tp._egt_degf->setFloatValue(
 678                         pe->getEGT() * K2DEGF + K2DEGFOFFSET);
 679                 tp._oil_temperature_degf->setFloatValue(
 680                         pe->getOilTemp() * K2DEGF + K2DEGFOFFSET);
 681                 tp._boost_gauge_inhg->setFloatValue(
 682                         pe->getBoost() * (1/INHG2PA));
 683             } else if(p->getEngine()->isTurbineEngine()) {
 684                 TurbineEngine* te = p->getEngine()->isTurbineEngine();
 685                 tp._n2->setFloatValue(te->getN2());
 686             }
 687         }
 688
 689         if(t->getJet()) {
 690             Jet* j = t->getJet();
 691             tp._n1->setFloatValue(j->getN1());
 692             tp._n2->setFloatValue(j->getN2());
 693             tp._epr->setFloatValue(j->getEPR());
 694             tp._egt_degf->setFloatValue(
 695                     j->getEGT() * K2DEGF + K2DEGFOFFSET);
 696
 697             // These are "unmodeled" values that are still needed for
 698             // many cockpits.  Tie them all to the N1 speed, but
 699             // normalize the numbers to the range [0:1] so the
 700             // cockpit code can scale them to the right values.
 701             float pnorm = j->getPerfNorm();
 702             moveprop(node, "oilp-norm", pnorm, dt/3); // 3s seek time
 703             moveprop(node, "oilt-norm", pnorm, dt/30); // 30s
 704             moveprop(node, "itt-norm", pnorm, dt/1); // 1s
 705         }
 706     }
 707 }
 708
 709 Wing* FGFDM::parseWing(XMLAttributes* a, const char* type, Version * version)
 710 {
 711     Wing* w = new Wing(version);
 712
 713     float defDihed = 0;
 714     if(eq(type, "vstab"))
 715         defDihed = 90;
 716     else
 717         w->setMirror(true);
 718
 719     float pos[3];
 720     pos[0] = attrf(a, "x");
 721     pos[1] = attrf(a, "y");
 722     pos[2] = attrf(a, "z");
 723     w->setBase(pos);
 724
 725     w->setLength(attrf(a, "length"));
 726     w->setChord(attrf(a, "chord"));
 727     w->setSweep(attrf(a, "sweep", 0) * DEG2RAD);
 728     w->setTaper(attrf(a, "taper", 1));
 729     w->setDihedral(attrf(a, "dihedral", defDihed) * DEG2RAD);
 730     w->setCamber(attrf(a, "camber", 0));
 731
 732     // These come in with positive indicating positive AoA, but the
 733     // internals expect a rotation about the left-pointing Y axis, so
 734     // invert the sign.
 735     w->setIncidence(attrf(a, "incidence", 0) * DEG2RAD * -1);
 736     w->setTwist(attrf(a, "twist", 0) * DEG2RAD * -1);
 737
 738     // The 70% is a magic number that sorta kinda seems to match known
 739     // throttle settings to approach speed.
 740     w->setInducedDrag(0.7*attrf(a, "idrag", 1));
 741
 742     float effect = attrf(a, "effectiveness", 1);
 743     w->setDragScale(w->getDragScale()*effect);
 744
 745     _currObj = w;
 746     return w;
 747 }
 748
 749 Rotor* FGFDM::parseRotor(XMLAttributes* a, const char* type)
 750 {
 751     Rotor* w = new Rotor();
 752
 753     // float defDihed = 0;
 754
 755     float pos[3];
 756     pos[0] = attrf(a, "x");
 757     pos[1] = attrf(a, "y");
 758     pos[2] = attrf(a, "z");
 759     w->setBase(pos);
 760
 761     float normal[3];
 762     normal[0] = attrf(a, "nx");
 763     normal[1] = attrf(a, "ny");
 764     normal[2] = attrf(a, "nz");
 765     w->setNormal(normal);
 766
 767     float forward[3];
 768     forward[0] = attrf(a, "fx");
 769     forward[1] = attrf(a, "fy");
 770     forward[2] = attrf(a, "fz");
 771     w->setForward(forward);
 772
 773     w->setMaxCyclicail(attrf(a, "maxcyclicail", 7.6));
 774     w->setMaxCyclicele(attrf(a, "maxcyclicele", 4.94));
 775     w->setMinCyclicail(attrf(a, "mincyclicail", -7.6));
 776     w->setMinCyclicele(attrf(a, "mincyclicele", -4.94));
 777     w->setMaxCollective(attrf(a, "maxcollective", 15.8));
 778     w->setMinCollective(attrf(a, "mincollective", -0.2));
 779     w->setDiameter(attrf(a, "diameter", 10.2));
 780     w->setWeightPerBlade(attrf(a, "weightperblade", 44));
 781     w->setNumberOfBlades(attrf(a, "numblades", 4));
 782     w->setRelBladeCenter(attrf(a, "relbladecenter", 0.7));
 783     w->setDynamic(attrf(a, "dynamic", 0.7));
 784     w->setDelta3(attrf(a, "delta3", 0));
 785     w->setDelta(attrf(a, "delta", 0));
 786     w->setTranslift(attrf(a, "translift", 0.05));
 787     w->setC2(attrf(a, "dragfactor", 1));
 788     w->setStepspersecond(attrf(a, "stepspersecond", 120));
 789     w->setPhiNull((attrf(a, "phi0", 0))*YASIM_PI/180);
 790     w->setRPM(attrf(a, "rpm", 424));
 791     w->setRelLenHinge(attrf(a, "rellenflaphinge", 0.07));
 792     w->setAlpha0((attrf(a, "flap0", -5))*YASIM_PI/180);
 793     w->setAlphamin((attrf(a, "flapmin", -15))/180*YASIM_PI);
 794     w->setAlphamax((attrf(a, "flapmax",  15))*YASIM_PI/180);
 795     w->setAlpha0factor(attrf(a, "flap0factor", 1));
 796     w->setTeeterdamp(attrf(a,"teeterdamp",.0001));
 797     w->setMaxteeterdamp(attrf(a,"maxteeterdamp",1000));
 798     w->setRelLenTeeterHinge(attrf(a,"rellenteeterhinge",0.01));
 799     w->setBalance(attrf(a,"balance",1.0));
 800     w->setMinTiltYaw(attrf(a,"mintiltyaw",0.0));
 801     w->setMinTiltPitch(attrf(a,"mintiltpitch",0.0));
 802     w->setMinTiltRoll(attrf(a,"mintiltroll",0.0));
 803     w->setMaxTiltYaw(attrf(a,"maxtiltyaw",0.0));
 804     w->setMaxTiltPitch(attrf(a,"maxtiltpitch",0.0));
 805     w->setMaxTiltRoll(attrf(a,"maxtiltroll",0.0));
 806     w->setTiltCenterX(attrf(a,"tiltcenterx",0.0));
 807     w->setTiltCenterY(attrf(a,"tiltcentery",0.0));
 808     w->setTiltCenterZ(attrf(a,"tiltcenterz",0.0));
 809     w->setDownwashFactor(attrf(a, "downwashfactor", 1));
 810     if(attrb(a,"ccw"))
 811        w->setCcw(1);
 812     if(attrb(a,"sharedflaphinge"))
 813        w->setSharedFlapHinge(true);
 814
 815     if(a->hasAttribute("name"))
 816        w->setName(a->getValue("name") );
 817     if(a->hasAttribute("alphaout0"))
 818        w->setAlphaoutput(0,a->getValue("alphaout0") );
 819     if(a->hasAttribute("alphaout1"))  w->setAlphaoutput(1,a->getValue("alphaout1") );
 820     if(a->hasAttribute("alphaout2"))  w->setAlphaoutput(2,a->getValue("alphaout2") );
 821     if(a->hasAttribute("alphaout3"))  w->setAlphaoutput(3,a->getValue("alphaout3") );
 822     if(a->hasAttribute("coneout"))  w->setAlphaoutput(4,a->getValue("coneout") );
 823     if(a->hasAttribute("yawout"))   w->setAlphaoutput(5,a->getValue("yawout") );
 824     if(a->hasAttribute("rollout"))  w->setAlphaoutput(6,a->getValue("rollout") );
 825
 826     w->setPitchA(attrf(a, "pitch-a", 10));
 827     w->setPitchB(attrf(a, "pitch-b", 10));
 828     w->setForceAtPitchA(attrf(a, "forceatpitch-a", 3000));
 829     w->setPowerAtPitch0(attrf(a, "poweratpitch-0", 300));
 830     w->setPowerAtPitchB(attrf(a, "poweratpitch-b", 3000));
 831     if(attrb(a,"notorque"))
 832        w->setNotorque(1);
 833
 834 #define p(x) if (a->hasAttribute(#x)) w->setParameter((char *)#x,attrf(a,#x) );
 835 #define p2(x,y) if (a->hasAttribute(y)) w->setParameter((char *)#x,attrf(a,y) );
 836     p2(translift_ve,"translift-ve")
 837     p2(translift_maxfactor,"translift-maxfactor")
 838     p2(ground_effect_constant,"ground-effect-constant")
 839     p2(vortex_state_lift_factor,"vortex-state-lift-factor")
 840     p2(vortex_state_c1,"vortex-state-c1")
 841     p2(vortex_state_c2,"vortex-state-c2")
 842     p2(vortex_state_c3,"vortex-state_c3")
 843     p2(vortex_state_e1,"vortex-state-e1")
 844     p2(vortex_state_e2,"vortex-state-e2")
 845     p(twist)
 846     p2(number_of_segments,"number-of-segments")
 847     p2(number_of_parts,"number-of-parts")
 848     p2(rel_len_where_incidence_is_measured,"rel-len-where-incidence-is-measured")
 849     p(chord)
 850     p(taper)
 851     p2(airfoil_incidence_no_lift,"airfoil-incidence-no-lift")
 852     p2(rel_len_blade_start,"rel-len-blade-start")
 853     p2(incidence_stall_zero_speed,"incidence-stall-zero-speed")
 854     p2(incidence_stall_half_sonic_speed,"incidence-stall-half-sonic-speed")
 855     p2(lift_factor_stall,"lift-factor-stall")
 856     p2(stall_change_over,"stall-change-over")
 857     p2(drag_factor_stall,"drag-factor-stall")
 858     p2(airfoil_lift_coefficient,"airfoil-lift-coefficient")
 859     p2(airfoil_drag_coefficient0,"airfoil-drag-coefficient0")
 860     p2(airfoil_drag_coefficient1,"airfoil-drag-coefficient1")
 861     p2(cyclic_factor,"cyclic-factor")
 862     p2(rotor_correction_factor,"rotor-correction-factor")
 863 #undef p
 864 #undef p2
 865     _currObj = w;
 866     return w;
 867 }
 868
 869 void FGFDM::parsePistonEngine(XMLAttributes* a)
 870 {
 871     float engP = attrf(a, "eng-power") * HP2W;
 872     float engS = attrf(a, "eng-rpm") * RPM2RAD;
 873
 874     PistonEngine* eng = new PistonEngine(engP, engS);
 875
 876     if(a->hasAttribute("displacement"))
 877         eng->setDisplacement(attrf(a, "displacement") * CIN2CM);
 878
 879     if(a->hasAttribute("compression"))
 880         eng->setCompression(attrf(a, "compression"));
 881
 882     if(a->hasAttribute("min-throttle"))
 883         eng->setMinThrottle(attrf(a, "min-throttle"));
 884
 885     if(a->hasAttribute("turbo-mul")) {
 886         float mul = attrf(a, "turbo-mul");
 887         float mp = attrf(a, "wastegate-mp", 1e6) * INHG2PA;
 888         eng->setTurboParams(mul, mp);
 889         eng->setTurboLag(attrf(a, "turbo-lag", 2));
 890     }
 891
 892     if(a->hasAttribute("supercharger"))
 893         eng->setSupercharger(attrb(a, "supercharger"));
 894
 895     ((PropEngine*)_currObj)->setEngine(eng);
 896 }
 897
 898 void FGFDM::parseTurbineEngine(XMLAttributes* a)
 899 {
 900     float power = attrf(a, "eng-power") * HP2W;
 901     float omega = attrf(a, "eng-rpm") * RPM2RAD;
 902     float alt = attrf(a, "alt") * FT2M;
 903     float flatRating = attrf(a, "flat-rating") * HP2W;
 904     TurbineEngine* eng = new TurbineEngine(power, omega, alt, flatRating);
 905
 906     if(a->hasAttribute("n2-low-idle"))
 907         eng->setN2Range(attrf(a, "n2-low-idle"), attrf(a, "n2-high-idle"),
 908                         attrf(a, "n2-max"));
 909
 910     // Nasty units conversion: lbs/hr per hp -> kg/s per watt
 911     if(a->hasAttribute("bsfc"))
 912         eng->setFuelConsumption(attrf(a, "bsfc") * (LBS2KG/(3600*HP2W)));
 913
 914     ((PropEngine*)_currObj)->setEngine(eng);
 915 }
 916
 917 void FGFDM::parsePropeller(XMLAttributes* a)
 918 {
 919     // Legacy Handling for the old engines syntax:
 920     PistonEngine* eng = 0;
 921     if(a->hasAttribute("eng-power")) {
 922         SG_LOG(SG_FLIGHT,SG_ALERT, "WARNING: "
 923                << "Legacy engine definition in YASim configuration file.  "
 924                << "Please fix.");
 925         float engP = attrf(a, "eng-power") * HP2W;
 926         float engS = attrf(a, "eng-rpm") * RPM2RAD;
 927         eng = new PistonEngine(engP, engS);
 928         if(a->hasAttribute("displacement"))
 929             eng->setDisplacement(attrf(a, "displacement") * CIN2CM);
 930         if(a->hasAttribute("compression"))
 931             eng->setCompression(attrf(a, "compression"));
 932         if(a->hasAttribute("turbo-mul")) {
 933             float mul = attrf(a, "turbo-mul");
 934             float mp = attrf(a, "wastegate-mp", 1e6) * INHG2PA;
 935             eng->setTurboParams(mul, mp);
 936         }
 937     }
 938
 939     // Now parse the actual propeller definition:
 940     float cg[3];
 941     cg[0] = attrf(a, "x");
 942     cg[1] = attrf(a, "y");
 943     cg[2] = attrf(a, "z");
 944     float mass = attrf(a, "mass") * LBS2KG;
 945     float moment = attrf(a, "moment");
 946     float radius = attrf(a, "radius");
 947     float speed = attrf(a, "cruise-speed") * KTS2MPS;
 948     float omega = attrf(a, "cruise-rpm") * RPM2RAD;
 949     float power = attrf(a, "cruise-power") * HP2W;
 950     float rho = Atmosphere::getStdDensity(attrf(a, "cruise-alt") * FT2M);
 951
 952     Propeller* prop = new Propeller(radius, speed, omega, rho, power);
 953     PropEngine* thruster = new PropEngine(prop, eng, moment);
 954     _airplane.addThruster(thruster, mass, cg);
 955
 956     // Set the stops (fine = minimum pitch, coarse = maximum pitch)
 957     float fine_stop = attrf(a, "fine-stop", 0.25f);
 958     float coarse_stop = attrf(a, "coarse-stop", 4.0f);
 959     prop->setStops(fine_stop, coarse_stop);
 960
 961     if(a->hasAttribute("takeoff-power")) {
 962         float power0 = attrf(a, "takeoff-power") * HP2W;
 963         float omega0 = attrf(a, "takeoff-rpm") * RPM2RAD;
 964         prop->setTakeoff(omega0, power0);
 965     }
 966
 967     if(a->hasAttribute("max-rpm")) {
 968         float max = attrf(a, "max-rpm") * RPM2RAD;
 969         float min = attrf(a, "min-rpm") * RPM2RAD;
 970         thruster->setVariableProp(min, max);
 971     }
 972
 973     if(attrb(a, "contra"))
 974         thruster->setContraPair(true);
 975
 976     if(a->hasAttribute("manual-pitch")) {
 977         prop->setManualPitch();
 978     }
 979
 980     thruster->setGearRatio(attrf(a, "gear-ratio", 1));
 981
 982     char buf[64];
 983     sprintf(buf, "/engines/engine[%d]", _nextEngine++);
 984     EngRec* er = new EngRec();
 985     er->eng = thruster;
 986     er->prefix = dup(buf);
 987     _thrusters.add(er);
 988
 989     _currObj = thruster;
 990 }
 991
 992 // Turns a string axis name into an integer for use by the
 993 // ControlMap.  Creates a new axis if this one hasn't been defined
 994 // yet.
 995 int FGFDM::parseAxis(const char* name)
 996 {
 997     for(int i=0; i<_axes.size(); i++) {
 998         AxisRec* a = (AxisRec*)_axes.get(i);
 999         if(eq(a->name, name))
1000             return a->handle;
1001     }
1002
1003     // Not there, make a new one.
1004     AxisRec* a = new AxisRec();
1005     a->name = dup(name);
1006     fgGetNode( a->name, true ); // make sure the property name exists
1007     a->handle = _airplane.getControlMap()->newInput();
1008     _axes.add(a);
1009     return a->handle;
1010 }
1011
1012 int FGFDM::parseOutput(const char* name)
1013 {
1014     if(eq(name, "THROTTLE"))  return ControlMap::THROTTLE;
1015     if(eq(name, "MIXTURE"))   return ControlMap::MIXTURE;
1016     if(eq(name, "CONDLEVER")) return ControlMap::CONDLEVER;
1017     if(eq(name, "STARTER"))   return ControlMap::STARTER;
1018     if(eq(name, "MAGNETOS"))  return ControlMap::MAGNETOS;
1019     if(eq(name, "ADVANCE"))   return ControlMap::ADVANCE;
1020     if(eq(name, "REHEAT"))    return ControlMap::REHEAT;
1021     if(eq(name, "BOOST"))     return ControlMap::BOOST;
1022     if(eq(name, "VECTOR"))    return ControlMap::VECTOR;
1023     if(eq(name, "PROP"))      return ControlMap::PROP;
1024     if(eq(name, "BRAKE"))     return ControlMap::BRAKE;
1025     if(eq(name, "STEER"))     return ControlMap::STEER;
1026     if(eq(name, "EXTEND"))    return ControlMap::EXTEND;
1027     if(eq(name, "HEXTEND"))   return ControlMap::HEXTEND;
1028     if(eq(name, "LEXTEND"))   return ControlMap::LEXTEND;
1029         if(eq(name, "LACCEL"))    return ControlMap::LACCEL;
1030     if(eq(name, "INCIDENCE")) return ControlMap::INCIDENCE;
1031     if(eq(name, "FLAP0"))     return ControlMap::FLAP0;
1032     if(eq(name, "FLAP0EFFECTIVENESS"))   return ControlMap::FLAP0EFFECTIVENESS;
1033     if(eq(name, "FLAP1"))     return ControlMap::FLAP1;
1034     if(eq(name, "FLAP1EFFECTIVENESS"))   return ControlMap::FLAP1EFFECTIVENESS;
1035     if(eq(name, "SLAT"))      return ControlMap::SLAT;
1036     if(eq(name, "SPOILER"))   return ControlMap::SPOILER;
1037     if(eq(name, "CASTERING")) return ControlMap::CASTERING;
1038     if(eq(name, "PROPPITCH")) return ControlMap::PROPPITCH;
1039     if(eq(name, "PROPFEATHER")) return ControlMap::PROPFEATHER;
1040     if(eq(name, "COLLECTIVE")) return ControlMap::COLLECTIVE;
1041     if(eq(name, "CYCLICAIL")) return ControlMap::CYCLICAIL;
1042     if(eq(name, "CYCLICELE")) return ControlMap::CYCLICELE;
1043     if(eq(name, "TILTROLL")) return ControlMap::TILTROLL;
1044     if(eq(name, "TILTPITCH")) return ControlMap::TILTPITCH;
1045     if(eq(name, "TILTYAW")) return ControlMap::TILTYAW;
1046     if(eq(name, "ROTORGEARENGINEON")) return ControlMap::ROTORENGINEON;
1047     if(eq(name, "ROTORBRAKE")) return ControlMap::ROTORBRAKE;
1048     if(eq(name, "ROTORENGINEMAXRELTORQUE"))
1049         return ControlMap::ROTORENGINEMAXRELTORQUE;
1050     if(eq(name, "ROTORRELTARGET")) return ControlMap::ROTORRELTARGET;
1051     if(eq(name, "ROTORBALANCE")) return ControlMap::ROTORBALANCE;
1052     if(eq(name, "REVERSE_THRUST")) return ControlMap::REVERSE_THRUST;
1053     if(eq(name, "WASTEGATE")) return ControlMap::WASTEGATE;
1054     if(eq(name, "WINCHRELSPEED")) return ControlMap::WINCHRELSPEED;
1055     if(eq(name, "HITCHOPEN")) return ControlMap::HITCHOPEN;
1056     if(eq(name, "PLACEWINCH")) return ControlMap::PLACEWINCH;
1057     if(eq(name, "FINDAITOW")) return ControlMap::FINDAITOW;
1058
1059     SG_LOG(SG_FLIGHT,SG_ALERT,"Unrecognized control type '"
1060            << name << "' in YASim aircraft description.");
1061     exit(1);
1062
1063 }
1064
1065 void FGFDM::parseWeight(XMLAttributes* a)
1066 {
1067     WeightRec* wr = new WeightRec();
1068
1069     float v[3];
1070     v[0] = attrf(a, "x");
1071     v[1] = attrf(a, "y");
1072     v[2] = attrf(a, "z");
1073
1074     wr->prop = dup(a->getValue("mass-prop"));
1075     wr->size = attrf(a, "size", 0);
1076     wr->handle = _airplane.addWeight(v, wr->size);
1077
1078     _weights.add(wr);
1079 }
1080
1081 bool FGFDM::eq(const char* a, const char* b)
1082 {
1083     // Figure it out for yourself. :)
1084     while(*a && *b && *a == *b) { a++; b++; }
1085     return !(*a || *b);
1086 }
1087
1088 char* FGFDM::dup(const char* s)
1089 {
1090     int len=0;
1091     while(s[len++]);
1092     char* s2 = new char[len+1];
1093     char* p = s2;
1094     while((*p++ = *s++));
1095     s2[len] = 0;
1096     return s2;
1097 }
1098
1099 int FGFDM::attri(XMLAttributes* atts, const char* attr)
1100 {
1101     if(!atts->hasAttribute(attr)) {
1102         SG_LOG(SG_FLIGHT,SG_ALERT,"Missing '" << attr <<
1103                "' in YASim aircraft description");
1104         exit(1);
1105     }
1106     return attri(atts, attr, 0);
1107 }
1108
1109 int FGFDM::attri(XMLAttributes* atts, const char* attr, int def)
1110 {
1111     const char* val = atts->getValue(attr);
1112     if(val == 0) return def;
1113     else         return atol(val);
1114 }
1115
1116 float FGFDM::attrf(XMLAttributes* atts, const char* attr)
1117 {
1118     if(!atts->hasAttribute(attr)) {
1119         SG_LOG(SG_FLIGHT,SG_ALERT,"Missing '" << attr <<
1120                "' in YASim aircraft description");
1121         exit(1);
1122     }
1123     return attrf(atts, attr, 0);
1124 }
1125
1126 float FGFDM::attrf(XMLAttributes* atts, const char* attr, float def)
1127 {
1128     const char* val = atts->getValue(attr);
1129     if(val == 0) return def;
1130     else         return (float)atof(val);
1131 }
1132
1133 double FGFDM::attrd(XMLAttributes* atts, const char* attr)
1134 {
1135     if(!atts->hasAttribute(attr)) {
1136         SG_LOG(SG_FLIGHT,SG_ALERT,"Missing '" << attr <<
1137                "' in YASim aircraft description");
1138         exit(1);
1139     }
1140     return attrd(atts, attr, 0);
1141 }
1142
1143 double FGFDM::attrd(XMLAttributes* atts, const char* attr, double def)
1144 {
1145     const char* val = atts->getValue(attr);
1146     if(val == 0) return def;
1147     else         return atof(val);
1148 }
1149
1150 // ACK: the dreaded ambiguous string boolean.  Remind me to shoot Maik
1151 // when I have a chance. :).  Unless you have a parser that can check
1152 // symbol constants (we don't), this kind of coding is just a Bad
1153 // Idea.  This implementation, for example, silently returns a boolean
1154 // falsehood for values of "1", "yes", "True", and "TRUE".  Which is
1155 // especially annoying preexisting boolean attributes in the same
1156 // parser want to see "1" and will choke on a "true"...
1157 //
1158 // Unfortunately, this usage creeped into existing configuration files
1159 // while I wasn't active, and it's going to be hard to remove.  Issue
1160 // a warning to nag people into changing their ways for now...
1161 bool FGFDM::attrb(XMLAttributes* atts, const char* attr)
1162 {
1163     const char* val = atts->getValue(attr);
1164     if(val == 0) return false;
1165
1166     if(eq(val,"true")) {
1167         SG_LOG(SG_FLIGHT, SG_ALERT, "Warning: " <<
1168                "deprecated 'true' boolean in YASim configuration file.  " <<
1169                "Use numeric booleans (attribute=\"1\") instead");
1170         return true;
1171     }
1172     return attri(atts, attr, 0) ? true : false;
1173 }
1174
1175 }; // namespace yasim