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