#include <Main/fg_props.hxx>
+#include "Math.hpp"
#include "Jet.hpp"
#include "SimpleJet.hpp"
#include "Gear.hpp"
#include "PropEngine.hpp"
#include "Propeller.hpp"
#include "PistonEngine.hpp"
+#include "TurbineEngine.hpp"
+#include "Rotor.hpp"
+#include "Rotorpart.hpp"
+#include "Rotorblade.hpp"
#include "FGFDM.hpp"
+
namespace yasim {
// Some conversion factors
static const float HP2W = 745.700;
static const float INHG2PA = 3386.389;
static const float K2DEGF = 1.8;
+static const float K2DEGFOFFSET = -459.4;
static const float CIN2CM = 1.6387064e-5;
+static const float YASIM_PI = 3.14159265358979323846;
+
+static const float NM2FTLB = (1/(LBS2N*FT2M));
// Stubs, so that this can be compiled without the FlightGear
// binary. What's the best way to handle this?
{
_nextEngine = 0;
- // Map /controls/elevator to the approach elevator control. This
+ // Map /controls/flight/elevator to the approach elevator control. This
// should probably be settable, but there are very few aircraft
// who trim their approaches using things other than elevator.
- _airplane.setElevatorControl(parseAxis("/controls/elevator-trim"));
+ _airplane.setElevatorControl(parseAxis("/controls/flight/elevator-trim"));
+
+ // FIXME: read seed from somewhere?
+ int seed = 0;
+ _turb = new Turbulence(10, seed);
}
FGFDM::~FGFDM()
{
getExternalInput(dt);
_airplane.iterate(dt);
+
+ // Do fuel stuff (FIXME: should stash SGPropertyNode objects here)
+ char buf[256];
+ for(int i=0; i<_airplane.numThrusters(); i++) {
+ Thruster* t = _airplane.getThruster(i);
+
+ sprintf(buf, "/engines/engine[%d]/out-of-fuel", i);
+ t->setFuelState(!fgGetBool(buf));
+
+ sprintf(buf, "/engines/engine[%d]/fuel-consumed-lbs", i);
+ double consumed = fgGetDouble(buf) + dt * KG2LBS * t->getFuelFlow();
+ fgSetDouble(buf, consumed);
+ }
+ for(int i=0; i<_airplane.numTanks(); i++) {
+ sprintf(buf, "/consumables/fuel/tank[%d]/level-lbs", i);
+ _airplane.setFuel(i, LBS2KG * fgGetFloat(buf));
+ }
+ _airplane.calcFuelWeights();
+
setOutputProperties();
}
// Allows the user to start with something other than full fuel
_airplane.setFuelFraction(fgGetFloat("/sim/fuel-fraction", 1));
+ // Read out the resulting fuel state
+ char buf[256];
+ for(int i=0; i<_airplane.numTanks(); i++) {
+ sprintf(buf, "/consumables/fuel/tank[%d]/level-lbs", i);
+ fgSetDouble(buf, _airplane.getFuel(i) * KG2LBS);
+
+ double density = _airplane.getFuelDensity(i);
+ sprintf(buf, "/consumables/fuel/tank[%d]/density-ppg", i);
+ fgSetDouble(buf, density * (KG2LBS/CM2GALS));
+
+ sprintf(buf, "/consumables/fuel/tank[%d]/level-gal_us", i);
+ fgSetDouble(buf, _airplane.getFuel(i) * CM2GALS / density);
+
+ sprintf(buf, "/consumables/fuel/tank[%d]/capacity-gal_us", i);
+ fgSetDouble(buf, CM2GALS * _airplane.getTankCapacity(i)/density);
+ }
+
// This has a nasty habit of being false at startup. That's not
// good.
- fgSetBool("/controls/gear-down", true);
+ fgSetBool("/controls/gear/gear-down", true);
+
+ _airplane.getModel()->setTurbulence(_turb);
}
// Not the worlds safest parser. But it's short & sweet.
float spd = attrf(a, "speed") * KTS2MPS;
float alt = attrf(a, "alt", 0) * FT2M;
float aoa = attrf(a, "aoa", 0) * DEG2RAD;
- _airplane.setApproach(spd, alt, aoa);
+ _airplane.setApproach(spd, alt, aoa, attrf(a, "fuel", 0.2));
_cruiseCurr = false;
} else if(eq(name, "cruise")) {
float spd = attrf(a, "speed") * KTS2MPS;
float alt = attrf(a, "alt") * FT2M;
- _airplane.setCruise(spd, alt);
+ _airplane.setCruise(spd, alt, attrf(a, "fuel", 0.5));
_cruiseCurr = true;
+ } else if(eq(name, "solve-weight")) {
+ int idx = attri(a, "idx");
+ float wgt = attrf(a, "weight") * LBS2KG;
+ _airplane.addSolutionWeight(!_cruiseCurr, idx, wgt);
} else if(eq(name, "cockpit")) {
v[0] = attrf(a, "x");
v[1] = attrf(a, "y");
v[2] = attrf(a, "z");
_airplane.setPilotPos(v);
+ } else if(eq(name, "rotor")) {
+ _airplane.addRotor(parseRotor(a, name));
} else if(eq(name, "wing")) {
_airplane.setWing(parseWing(a, name));
} else if(eq(name, "hstab")) {
_airplane.setTail(parseWing(a, name));
- } else if(eq(name, "vstab")) {
+ } else if(eq(name, "vstab") || eq(name, "mstab")) {
_airplane.addVStab(parseWing(a, name));
+ } else if(eq(name, "piston-engine")) {
+ parsePistonEngine(a);
+ } else if(eq(name, "turbine-engine")) {
+ parseTurbineEngine(a);
} else if(eq(name, "propeller")) {
parsePropeller(a);
} else if(eq(name, "thruster")) {
j->setMaxThrust(attrf(a, "thrust") * LBS2N,
attrf(a, "afterburner", 0) * LBS2N);
j->setVectorAngle(attrf(a, "rotate", 0) * DEG2RAD);
+ j->setReverseThrust(attrf(a, "reverse", 0.2));
float n1min = attrf(a, "n1-idle", 55);
float n1max = attrf(a, "n1-max", 102);
float n2max = attrf(a, "n2-max", 103);
j->setRPMs(n1min, n1max, n2min, n2max);
- if(a->hasAttribute("tsfc")) j->setTSFC(attrf(a, "tsfc"));
+ j->setTSFC(attrf(a, "tsfc", 0.8));
if(a->hasAttribute("egt")) j->setEGT(attrf(a, "egt"));
if(a->hasAttribute("epr")) j->setEPR(attrf(a, "epr"));
if(a->hasAttribute("exhaust-speed"))
} else if(eq(name, "spoiler")) {
((Wing*)_currObj)->setSpoiler(attrf(a, "start"), attrf(a, "end"),
attrf(a, "lift"), attrf(a, "drag"));
+ /* } else if(eq(name, "collective")) {
+ ((Rotor*)_currObj)->setcollective(attrf(a, "min"), attrf(a, "max"));
+ } else if(eq(name, "cyclic")) {
+ ((Rotor*)_currObj)->setcyclic(attrf(a, "ail"), attrf(a, "ele"));
+ */
} else if(eq(name, "actionpt")) {
v[0] = attrf(a, "x");
v[1] = attrf(a, "y");
void FGFDM::getExternalInput(float dt)
{
+ char buf[256];
+
+ _turb->setMagnitude(fgGetFloat("/environment/turbulence/magnitude-norm"));
+ _turb->update(dt, fgGetFloat("/environment/turbulence/rate-hz"));
+
// The control axes
ControlMap* cm = _airplane.getControlMap();
cm->reset();
WeightRec* wr = (WeightRec*)_weights.get(i);
_airplane.setWeight(wr->handle, LBS2KG * fgGetFloat(wr->prop));
}
+
+ for(i=0; i<_thrusters.size(); i++) {
+ EngRec* er = (EngRec*)_thrusters.get(i);
+ Thruster* t = er->eng;
+
+ if(t->getPropEngine()) {
+ PropEngine* p = t->getPropEngine();
+ sprintf(buf, "%s/rpm", er->prefix);
+ p->setOmega(fgGetFloat(buf, 500) * RPM2RAD);
+ }
+ }
}
void FGFDM::setOutputProperties()
{
- char buf[256];
+ // char buf[256];
int i;
float grossWgt = _airplane.getModel()->getBody()->getTotalMass() * KG2LBS;
p->prop->setFloatValue(val);
}
- float fuelDensity = 718.95; // default to gasoline: ~6 lb/gal
- for(i=0; i<_airplane.numTanks(); i++) {
- fuelDensity = _airplane.getFuelDensity(i);
- sprintf(buf, "/consumables/fuel/tank[%d]/level-gal_us", i);
- fgSetFloat(buf, CM2GALS*_airplane.getFuel(i)/fuelDensity);
+ for(i=0; i<_airplane.getNumRotors(); i++) {
+ Rotor*r=(Rotor*)_airplane.getRotor(i);
+ int j = 0;
+ float f;
+ char b[256];
+ while(j = r->getValueforFGSet(j, b, &f))
+ if(b[0]) fgSetFloat(b,f);
+
+ for(j=0; j < r->numRotorparts(); j++) {
+ Rotorpart* s = (Rotorpart*)r->getRotorpart(j);
+ char *b;
+ int k;
+ for(k=0; k<2; k++) {
+ b=s->getAlphaoutput(k);
+ if(b[0]) fgSetFloat(b, s->getAlpha(k));
+ }
+ }
+ for(j=0; j < r->numRotorblades(); j++) {
+ Rotorblade* s = (Rotorblade*)r->getRotorblade(j);
+ char *b;
+ int k;
+ for (k=0; k<2; k++) {
+ b = s->getAlphaoutput(k);
+ if(b[0]) fgSetFloat(b, s->getAlpha(k));
+ }
+ }
}
+ float fuelDensity = _airplane.getFuelDensity(0); // HACK
for(i=0; i<_thrusters.size(); i++) {
EngRec* er = (EngRec*)_thrusters.get(i);
Thruster* t = er->eng;
+ SGPropertyNode * node = fgGetNode("engines/engine", i, true);
- sprintf(buf, "%s/fuel-flow-gph", er->prefix);
- fgSetFloat(buf, (t->getFuelFlow()/fuelDensity) * 3600 * CM2GALS);
+ // Set: running, cranking, prop-thrust, max-hp, power-pct
+ node->setBoolValue("running", t->isRunning());
+ node->setBoolValue("cranking", t->isCranking());
+
+ float tmp[3];
+ t->getThrust(tmp);
+ float lbs = Math::mag3(tmp) * (KG2LBS/9.8);
+ node->setFloatValue("prop-thrust", lbs); // Deprecated name
+ node->setFloatValue("thrust-lbs", lbs);
+ node->setFloatValue("fuel-flow-gph",
+ (t->getFuelFlow()/fuelDensity) * 3600 * CM2GALS);
if(t->getPropEngine()) {
PropEngine* p = t->getPropEngine();
-
- sprintf(buf, "%s/rpm", er->prefix);
- fgSetFloat(buf, p->getOmega() / RPM2RAD);
- }
-
- if(t->getPistonEngine()) {
- PistonEngine* p = t->getPistonEngine();
-
- sprintf(buf, "%s/mp-osi", er->prefix);
- fgSetFloat(buf, p->getMP() * (1/INHG2PA));
-
- sprintf(buf, "%s/egt-degf", er->prefix);
- fgSetFloat(buf, p->getEGT() * K2DEGF + 459.4);
+ node->setFloatValue("rpm", p->getOmega() * (1/RPM2RAD));
+ node->setFloatValue("torque-ftlb",
+ p->getEngine()->getTorque() * NM2FTLB);
+
+ if(p->getEngine()->isPistonEngine()) {
+ PistonEngine* pe = p->getEngine()->isPistonEngine();
+ node->setFloatValue("mp-osi", pe->getMP() * (1/INHG2PA));
+ node->setFloatValue("mp-inhg", pe->getMP() * (1/INHG2PA));
+ node->setFloatValue("egt-degf",
+ pe->getEGT() * K2DEGF + K2DEGFOFFSET);
+ } else if(p->getEngine()->isTurbineEngine()) {
+ TurbineEngine* te = p->getEngine()->isTurbineEngine();
+ node->setFloatValue("n2", te->getN2());
+ }
}
if(t->getJet()) {
Jet* j = t->getJet();
-
- sprintf(buf, "%s/n1", er->prefix);
- fgSetFloat(buf, j->getN1());
-
- sprintf(buf, "%s/n2", er->prefix);
- fgSetFloat(buf, j->getN2());
-
- sprintf(buf, "%s/epr", er->prefix);
- fgSetFloat(buf, j->getEPR());
-
- sprintf(buf, "%s/egt-degf", er->prefix);
- fgSetFloat(buf, j->getEGT() * K2DEGF + 459.4);
+ node->setFloatValue("n1", j->getN1());
+ node->setFloatValue("n2", j->getN2());
+ node->setFloatValue("epr", j->getEPR());
+ node->setFloatValue("egr-degf",
+ j->getEGT() * K2DEGF + K2DEGFOFFSET);
}
}
}
w->setDihedral(attrf(a, "dihedral", defDihed) * DEG2RAD);
w->setCamber(attrf(a, "camber", 0));
w->setIncidence(attrf(a, "incidence", 0) * DEG2RAD);
+ w->setTwist(attrf(a, "twist", 0) * DEG2RAD);
// The 70% is a magic number that sorta kinda seems to match known
// throttle settings to approach speed.
return w;
}
-void FGFDM::parsePropeller(XMLAttributes* a)
+Rotor* FGFDM::parseRotor(XMLAttributes* a, const char* type)
{
- float cg[3];
- cg[0] = attrf(a, "x");
- cg[1] = attrf(a, "y");
- cg[2] = attrf(a, "z");
- float mass = attrf(a, "mass") * LBS2KG;
- float moment = attrf(a, "moment");
- float radius = attrf(a, "radius");
- float speed = attrf(a, "cruise-speed") * KTS2MPS;
- float omega = attrf(a, "cruise-rpm") * RPM2RAD;
- float power = attrf(a, "cruise-power") * HP2W;
- float rho = Atmosphere::getStdDensity(attrf(a, "cruise-alt") * FT2M);
+ Rotor* w = new Rotor();
- // Hack, fix this pronto:
+ // float defDihed = 0;
+
+ float pos[3];
+ pos[0] = attrf(a, "x");
+ pos[1] = attrf(a, "y");
+ pos[2] = attrf(a, "z");
+ w->setBase(pos);
+
+ float normal[3];
+ normal[0] = attrf(a, "nx");
+ normal[1] = attrf(a, "ny");
+ normal[2] = attrf(a, "nz");
+ w->setNormal(normal);
+
+ float forward[3];
+ forward[0] = attrf(a, "fx");
+ forward[1] = attrf(a, "fy");
+ forward[2] = attrf(a, "fz");
+ w->setForward(forward);
+
+ w->setMaxCyclicail(attrf(a, "maxcyclicail", 7.6));
+ w->setMaxCyclicele(attrf(a, "maxcyclicele", 4.94));
+ w->setMinCyclicail(attrf(a, "mincyclicail", -7.6));
+ w->setMinCyclicele(attrf(a, "mincyclicele", -4.94));
+ w->setMaxCollective(attrf(a, "maxcollective", 15.8));
+ w->setMinCollective(attrf(a, "mincollective", -0.2));
+ w->setDiameter(attrf(a, "diameter", 10.2));
+ w->setWeightPerBlade(attrf(a, "weightperblade", 44));
+ w->setNumberOfBlades(attrf(a, "numblades", 4));
+ w->setRelBladeCenter(attrf(a, "relbladecenter", 0.7));
+ w->setDynamic(attrf(a, "dynamic", 0.7));
+ w->setDelta3(attrf(a, "delta3", 0));
+ w->setDelta(attrf(a, "delta", 0));
+ w->setTranslift(attrf(a, "translift", 0.05));
+ w->setC2(attrf(a, "dragfactor", 1));
+ w->setStepspersecond(attrf(a, "stepspersecond", 120));
+ w->setRPM(attrf(a, "rpm", 424));
+ w->setRelLenHinge(attrf(a, "rellenflaphinge", 0.07));
+ w->setAlpha0((attrf(a, "flap0", -5))*YASIM_PI/180);
+ w->setAlphamin((attrf(a, "flapmin", -15))/180*YASIM_PI);
+ w->setAlphamax((attrf(a, "flapmax", 15))*YASIM_PI/180);
+ w->setAlpha0factor(attrf(a, "flap0factor", 1));
+ w->setTeeterdamp(attrf(a,"teeterdamp",.0001));
+ w->setMaxteeterdamp(attrf(a,"maxteeterdamp",1000));
+ w->setRelLenTeeterHinge(attrf(a,"rellenteeterhinge",0.01));
+ void setAlphamin(float f);
+ void setAlphamax(float f);
+ void setAlpha0factor(float f);
+
+ if(attrb(a,"ccw"))
+ w->setCcw(1);
+
+ if(a->hasAttribute("name"))
+ w->setName(a->getValue("name") );
+ if(a->hasAttribute("alphaout0"))
+ w->setAlphaoutput(0,a->getValue("alphaout0") );
+ if(a->hasAttribute("alphaout1")) w->setAlphaoutput(1,a->getValue("alphaout1") );
+ if(a->hasAttribute("alphaout2")) w->setAlphaoutput(2,a->getValue("alphaout2") );
+ if(a->hasAttribute("alphaout3")) w->setAlphaoutput(3,a->getValue("alphaout3") );
+ if(a->hasAttribute("coneout")) w->setAlphaoutput(4,a->getValue("coneout") );
+ if(a->hasAttribute("yawout")) w->setAlphaoutput(5,a->getValue("yawout") );
+ if(a->hasAttribute("rollout")) w->setAlphaoutput(6,a->getValue("rollout") );
+
+ w->setPitchA(attrf(a, "pitch_a", 10));
+ w->setPitchB(attrf(a, "pitch_b", 10));
+ w->setForceAtPitchA(attrf(a, "forceatpitch_a", 3000));
+ w->setPowerAtPitch0(attrf(a, "poweratpitch_0", 300));
+ w->setPowerAtPitchB(attrf(a, "poweratpitch_b", 3000));
+ if(attrb(a,"notorque"))
+ w->setNotorque(1);
+ if(attrb(a,"simblades"))
+ w->setSimBlades(1);
+
+ _currObj = w;
+ return w;
+}
+
+void FGFDM::parsePistonEngine(XMLAttributes* a)
+{
float engP = attrf(a, "eng-power") * HP2W;
float engS = attrf(a, "eng-rpm") * RPM2RAD;
- Propeller* prop = new Propeller(radius, speed, omega, rho, power);
PistonEngine* eng = new PistonEngine(engP, engS);
- PropEngine* thruster = new PropEngine(prop, eng, moment);
- _airplane.addThruster(thruster, mass, cg);
if(a->hasAttribute("displacement"))
eng->setDisplacement(attrf(a, "displacement") * CIN2CM);
eng->setTurboParams(mul, mp);
}
+ ((PropEngine*)_currObj)->setEngine(eng);
+}
+
+void FGFDM::parseTurbineEngine(XMLAttributes* a)
+{
+ float power = attrf(a, "eng-power") * HP2W;
+ float omega = attrf(a, "eng-rpm") * RPM2RAD;
+ float alt = attrf(a, "alt") * FT2M;
+ float flatRating = attrf(a, "flat-rating") * HP2W;
+ TurbineEngine* eng = new TurbineEngine(power, omega, alt, flatRating);
+
+ if(a->hasAttribute("n2-low-idle"))
+ eng->setN2Range(attrf(a, "n2-low-idle"), attrf(a, "n2-high-idle"),
+ attrf(a, "n2-max"));
+
+ // Nasty units conversion: lbs/hr per hp -> kg/s per watt
+ if(a->hasAttribute("bsfc"))
+ eng->setFuelConsumption(attrf(a, "bsfc") * (LBS2KG/(3600*HP2W)));
+
+ ((PropEngine*)_currObj)->setEngine(eng);
+}
+
+void FGFDM::parsePropeller(XMLAttributes* a)
+{
+ // Legacy Handling for the old engines syntax:
+ PistonEngine* eng = 0;
+ if(a->hasAttribute("eng-power")) {
+ SG_LOG(SG_FLIGHT,SG_ALERT, "WARNING: "
+ << "Legacy engine definition in YASim configuration file. "
+ << "Please fix.");
+ float engP = attrf(a, "eng-power") * HP2W;
+ float engS = attrf(a, "eng-rpm") * RPM2RAD;
+ eng = new PistonEngine(engP, engS);
+ if(a->hasAttribute("displacement"))
+ eng->setDisplacement(attrf(a, "displacement") * CIN2CM);
+ if(a->hasAttribute("compression"))
+ eng->setCompression(attrf(a, "compression"));
+ if(a->hasAttribute("turbo-mul")) {
+ float mul = attrf(a, "turbo-mul");
+ float mp = attrf(a, "wastegate-mp", 1e6) * INHG2PA;
+ eng->setTurboParams(mul, mp);
+ }
+ }
+
+ // Now parse the actual propeller definition:
+ float cg[3];
+ cg[0] = attrf(a, "x");
+ cg[1] = attrf(a, "y");
+ cg[2] = attrf(a, "z");
+ float mass = attrf(a, "mass") * LBS2KG;
+ float moment = attrf(a, "moment");
+ float radius = attrf(a, "radius");
+ float speed = attrf(a, "cruise-speed") * KTS2MPS;
+ float omega = attrf(a, "cruise-rpm") * RPM2RAD;
+ float power = attrf(a, "cruise-power") * HP2W;
+ float rho = Atmosphere::getStdDensity(attrf(a, "cruise-alt") * FT2M);
+
+ Propeller* prop = new Propeller(radius, speed, omega, rho, power);
+ PropEngine* thruster = new PropEngine(prop, eng, moment);
+ _airplane.addThruster(thruster, mass, cg);
+
if(a->hasAttribute("takeoff-power")) {
float power0 = attrf(a, "takeoff-power") * HP2W;
float omega0 = attrf(a, "takeoff-rpm") * RPM2RAD;
thruster->setVariableProp(min, max);
}
+ if(a->hasAttribute("manual-pitch")) {
+ prop->setManualPitch();
+ }
+
+ thruster->setGearRatio(attrf(a, "gear-ratio", 1));
+
char buf[64];
sprintf(buf, "/engines/engine[%d]", _nextEngine++);
EngRec* er = new EngRec();
// Not there, make a new one.
AxisRec* a = new AxisRec();
a->name = dup(name);
+ fgGetNode( a->name, true ); // make sure the property name exists
a->handle = _airplane.getControlMap()->newInput();
_axes.add(a);
return a->handle;
{
if(eq(name, "THROTTLE")) return ControlMap::THROTTLE;
if(eq(name, "MIXTURE")) return ControlMap::MIXTURE;
+ if(eq(name, "CONDLEVER")) return ControlMap::CONDLEVER;
if(eq(name, "STARTER")) return ControlMap::STARTER;
if(eq(name, "MAGNETOS")) return ControlMap::MAGNETOS;
if(eq(name, "ADVANCE")) return ControlMap::ADVANCE;
if(eq(name, "SLAT")) return ControlMap::SLAT;
if(eq(name, "SPOILER")) return ControlMap::SPOILER;
if(eq(name, "CASTERING")) return ControlMap::CASTERING;
+ if(eq(name, "PROPPITCH")) return ControlMap::PROPPITCH;
+ if(eq(name, "PROPFEATHER")) return ControlMap::PROPFEATHER;
+ if(eq(name, "COLLECTIVE")) return ControlMap::COLLECTIVE;
+ if(eq(name, "CYCLICAIL")) return ControlMap::CYCLICAIL;
+ if(eq(name, "CYCLICELE")) return ControlMap::CYCLICELE;
+ if(eq(name, "ROTORENGINEON")) return ControlMap::ROTORENGINEON;
+ if(eq(name, "REVERSE_THRUST")) return ControlMap::REVERSE_THRUST;
SG_LOG(SG_FLIGHT,SG_ALERT,"Unrecognized control type '"
<< name << "' in YASim aircraft description.");
exit(1);
else return (float)atof(val);
}
+// ACK: the dreaded ambiguous string boolean. Remind me to shoot Maik
+// when I have a chance. :). Unless you have a parser that can check
+// symbol constants (we don't), this kind of coding is just a Bad
+// Idea. This implementation, for example, silently returns a boolean
+// falsehood for values of "1", "yes", "True", and "TRUE". Which is
+// especially annoying preexisting boolean attributes in the same
+// parser want to see "1" and will choke on a "true"...
+//
+// Unfortunately, this usage creeped into existing configuration files
+// while I wasn't active, and it's going to be hard to remove. Issue
+// a warning to nag people into changing their ways for now...
+bool FGFDM::attrb(XMLAttributes* atts, char* attr)
+{
+ const char* val = atts->getValue(attr);
+ if(val == 0) return false;
+
+ if(eq(val,"true")) {
+ SG_LOG(SG_FLIGHT, SG_ALERT, "Warning: " <<
+ "deprecated 'true' boolean in YASim configuration file. " <<
+ "Use numeric booleans (attribute=\"1\") instead");
+ return true;
+ }
+ return attri(atts, attr, 0) ? true : false;
+}
+
}; // namespace yasim