void CARDYNAMICS::UpdateWheelTransform()
{
for(int i = 0; i < WHEEL_POSITION_SIZE; ++i)
{
wheel_position[i] = GetWheelPositionAtDisplacement(WHEEL_POSITION(i), suspension[i].GetDisplacementPercent());
wheel_orientation[i] = Orientation() * GetWheelSteeringAndSuspensionOrientation(WHEEL_POSITION(i));
}
}
const BEZIER * GetCurrentPatch(const CAR *c)
{
const BEZIER *curr_patch = c->GetCurPatch(WHEEL_POSITION(0));
if (!curr_patch)
{
curr_patch = c->GetCurPatch(WHEEL_POSITION(1)); //let's try the other wheel
if (!curr_patch) return NULL;
}
return curr_patch;
}
void AI::calcMu(AI_Car *c)
{
int i;
float long_friction = 0.0;
float lat_friction = 0.0;
for (i=0; i<4; i++)
{
long_friction += c->car->GetTireMaxFx(WHEEL_POSITION(i));
lat_friction += c->car->GetTireMaxFy(WHEEL_POSITION(i));
}
float long_mu = FRICTION_FACTOR_LONG * long_friction * c->car->GetInvMass() / GRAVITY;
float lat_mu = FRICTION_FACTOR_LAT * lat_friction * c->car->GetInvMass() / GRAVITY;
if (!isnan(long_mu)) c->longitude_mu = long_mu;
if (!isnan(lat_mu)) c->lateral_mu = lat_mu;
}
float CAR::GetTireSquealAmount(WHEEL_POSITION i) const
{
const TRACKSURFACE & surface = dynamics.GetWheelContact(WHEEL_POSITION(i)).GetSurface();
if (surface.type == TRACKSURFACE::NONE) return 0;
btQuaternion wheelspace = dynamics.GetUprightOrientation(WHEEL_POSITION(i));
btVector3 groundvel = quatRotate(wheelspace.inverse(), dynamics.GetWheelVelocity(WHEEL_POSITION(i)));
float wheelspeed = dynamics.GetWheel(WHEEL_POSITION(i)).GetAngularVelocity() * dynamics.GetTire(WHEEL_POSITION(i)).GetRadius();
groundvel[0] -= wheelspeed;
groundvel[1] *= 2.0;
groundvel[2] = 0;
float squeal = (groundvel.length() - 3.0) * 0.2;
double slide = dynamics.GetTire(i).GetSlide() / dynamics.GetTire(i).GetIdealSlide();
double slip = dynamics.GetTire(i).GetSlip() / dynamics.GetTire(i).GetIdealSlip();
double maxratio = std::max(std::abs(slide), std::abs(slip));
float squealfactor = std::max(0.0, maxratio - 1.0);
squeal *= squealfactor;
if (squeal < 0) squeal = 0;
if (squeal > 1) squeal = 1;
return squeal;
}
void CAR::UpdateSounds(float dt)
{
if (!psound) return;
MATHVECTOR <float, 3> pos_car = GetPosition();
MATHVECTOR <float, 3> pos_eng = ToMathVector<float>(dynamics.GetEnginePosition());
psound->SetSourcePosition(roadnoise, pos_car[0], pos_car[1], pos_car[2]);
psound->SetSourcePosition(crashsound, pos_car[0], pos_car[1], pos_car[2]);
psound->SetSourcePosition(gearsound, pos_car[0], pos_car[1], pos_car[2]);
psound->SetSourcePosition(brakesound, pos_car[0], pos_car[1], pos_car[2]);
psound->SetSourcePosition(handbrakesound, pos_car[0], pos_car[1], pos_car[2]);
// update engine sounds
float rpm = GetEngineRPM();
float throttle = dynamics.GetEngine().GetThrottle();
float total_gain = 0.0;
std::vector<std::pair<size_t, float> > gainlist;
gainlist.reserve(enginesounds.size());
for (std::vector<ENGINESOUNDINFO>::iterator i = enginesounds.begin(); i != enginesounds.end(); ++i)
{
ENGINESOUNDINFO & info = *i;
float gain = 1.0;
if (rpm < info.minrpm)
{
gain = 0;
}
else if (rpm < info.fullgainrpmstart && info.fullgainrpmstart > info.minrpm)
{
gain *= (rpm - info.minrpm) / (info.fullgainrpmstart - info.minrpm);
}
if (rpm > info.maxrpm)
{
gain = 0;
}
else if (rpm > info.fullgainrpmend && info.fullgainrpmend < info.maxrpm)
{
gain *= 1.0 - (rpm - info.fullgainrpmend) / (info.maxrpm - info.fullgainrpmend);
}
if (info.power == ENGINESOUNDINFO::BOTH)
{
gain *= throttle * 0.5 + 0.5;
}
else if (info.power == ENGINESOUNDINFO::POWERON)
{
gain *= throttle;
}
else if (info.power == ENGINESOUNDINFO::POWEROFF)
{
gain *= (1.0-throttle);
}
total_gain += gain;
gainlist.push_back(std::make_pair(info.sound_source, gain));
float pitch = rpm / info.naturalrpm;
psound->SetSourcePosition(info.sound_source, pos_eng[0], pos_eng[1], pos_eng[2]);
psound->SetSourcePitch(info.sound_source, pitch);
}
// normalize gains
assert(total_gain >= 0.0);
for (std::vector<std::pair<size_t, float> >::iterator i = gainlist.begin(); i != gainlist.end(); ++i)
{
float gain;
if (total_gain == 0.0)
{
gain = 0.0;
}
else if (enginesounds.size() == 1 && enginesounds.back().power == ENGINESOUNDINFO::BOTH)
{
gain = i->second;
}
else
{
gain = i->second / total_gain;
}
psound->SetSourceGain(i->first, gain);
}
// update tire squeal sounds
for (int i = 0; i < 4; i++)
{
// make sure we don't get overlap
psound->SetSourceGain(gravelsound[i], 0.0);
psound->SetSourceGain(grasssound[i], 0.0);
psound->SetSourceGain(tiresqueal[i], 0.0);
float squeal = GetTireSquealAmount(WHEEL_POSITION(i));
float maxgain = 0.3;
float pitchvariation = 0.4;
size_t * sound_active;
const TRACKSURFACE & surface = dynamics.GetWheelContact(WHEEL_POSITION(i)).GetSurface();
if (surface.type == TRACKSURFACE::ASPHALT)
{
sound_active = tiresqueal;
}
else if (surface.type == TRACKSURFACE::GRASS)
{
sound_active = grasssound;
maxgain = 0.4; // up the grass sound volume a little
}
else if (surface.type == TRACKSURFACE::GRAVEL)
{
sound_active = gravelsound;
maxgain = 0.4;
}
else if (surface.type == TRACKSURFACE::CONCRETE)
{
sound_active = tiresqueal;
maxgain = 0.3;
pitchvariation = 0.25;
}
else if (surface.type == TRACKSURFACE::SAND)
{
sound_active = grasssound;
maxgain = 0.25; // quieter for sand
pitchvariation = 0.25;
}
else
{
sound_active = tiresqueal;
maxgain = 0.0;
}
btVector3 pos_wheel = dynamics.GetWheelPosition(WHEEL_POSITION(i));
btVector3 vel_wheel = dynamics.GetWheelVelocity(WHEEL_POSITION(i));
float pitch = (vel_wheel.length() - 5.0) * 0.1;
if (pitch < 0)
pitch = 0;
if (pitch > 1)
pitch = 1;
pitch = 1.0 - pitch;
pitch *= pitchvariation;
pitch = pitch + (1.0 - pitchvariation);
if (pitch < 0.1)
pitch = 0.1;
if (pitch > 4.0)
pitch = 4.0;
psound->SetSourcePosition(sound_active[i], pos_wheel[0], pos_wheel[1], pos_wheel[2]);
psound->SetSourcePitch(sound_active[i], pitch);
psound->SetSourceGain(sound_active[i], squeal * maxgain);
}
//update road noise sound
{
float gain = dynamics.GetVelocity().length();
if (gain < 0) gain = -gain;
gain *= 0.02;
gain *= gain;
if (gain > 1.0) gain = 1.0;
psound->SetSourceGain(roadnoise, gain);
}
/*
//update bump noise sound
{
for (int i = 0; i < 4; i++)
{
suspensionbumpdetection[i].Update(
dynamics.GetSuspension(WHEEL_POSITION(i)).GetVelocity(),
dynamics.GetSuspension(WHEEL_POSITION(i)).GetDisplacementFraction(),
dt);
if (suspensionbumpdetection[i].JustSettled())
{
float bumpsize = suspensionbumpdetection[i].GetTotalBumpSize();
const float breakevenms = 5.0;
float gain = bumpsize * GetSpeed() / breakevenms;
if (gain > 1)
gain = 1;
if (gain < 0)
gain = 0;
if (gain > 0 && !tirebump[i].Audible())
{
tirebump[i].SetGain(gain);
tirebump[i].Stop();
tirebump[i].Play();
}
}
}
}
//update crash sound
{
crashdetection.Update(GetSpeed(), dt);
float crashdecel = crashdetection.GetMaxDecel();
if (crashdecel > 0)
{
const float mingainat = 500;
const float maxgainat = 3000;
const float mingain = 0.1;
float gain = (crashdecel-mingainat)/(maxgainat-mingainat);
if (gain > 1)
gain = 1;
if (gain < mingain)
gain = mingain;
if (!crashsound.Audible())
{
crashsound.SetGain(gain);
crashsound.Stop();
crashsound.Play();
}
}
}
*/
// update gear sound
if (driver_view && gearsound_check != GetGear())
{
float gain = 0.0;
if (GetEngineRPM() != 0.0)
gain = GetEngineRPMLimit() / GetEngineRPM();
if (gain > 0.5)
gain = 0.5;
if (gain < 0.25)
gain = 0.25;
if (!psound->GetSourcePlaying(gearsound))
{
psound->ResetSource(gearsound);
psound->SetSourceGain(gearsound, gain);
}
gearsound_check = GetGear();
}
}
void PERFORMANCE_TESTING::TestStoppingDistance(bool abs, std::ostream & info_output, std::ostream & error_output)
{
info_output << "Testing stopping distance" << std::endl;
ResetCar();
car.dynamics.SetABS(abs);
double maxtime = 300.0;
double t = 0.;
double dt = .004;
int i = 0;
std::vector <float> inputs(CARINPUT::INVALID, 0.0);
inputs[CARINPUT::THROTTLE] = 1.0;
float stopthreshold = 0.1; //if the speed (in m/s) is less than this value, discontinue the testing
btVector3 stopstart; //where the stopping starts
float brakestartspeed = 26.82; //speed at which to start braking, in m/s (26.82 m/s is 60 mph)
bool accelerating = true; //switches to false once 60 mph is reached
while (t < maxtime)
{
if (accelerating)
{
inputs[CARINPUT::THROTTLE] = 1.0;
inputs[CARINPUT::BRAKE] = 0.0;
}
else
{
inputs[CARINPUT::THROTTLE] = 0.0;
inputs[CARINPUT::BRAKE] = 1.0;
inputs[CARINPUT::NEUTRAL] = 1.0;
}
car.HandleInputs(inputs);
world.update(dt);
if (car.dynamics.GetSpeed() >= brakestartspeed && accelerating) //stop accelerating and hit the brakes
{
accelerating = false;
stopstart = car.dynamics.GetWheelPosition(WHEEL_POSITION(0));
//std::cout << "hitting the brakes at " << t << ", " << car.dynamics.GetSpeed() << std::endl;
}
if (!accelerating && car.dynamics.GetSpeed() < stopthreshold)
{
break;
}
if (car.GetEngineRPM() < 1)
{
error_output << "Car stalled during launch, t=" << t << std::endl;
break;
}
if (i % (int)(1.0/dt) == 0) //every second
{
//std::cout << t << ", " << car.dynamics.GetSpeed() << ", " << car.GetGear() << ", " << car.GetEngineRPM() << std::endl;
}
t += dt;
i++;
}
btVector3 stopend = car.dynamics.GetWheelPosition(WHEEL_POSITION(0));
info_output << "60-0 stopping distance ";
if (abs)
info_output << "(ABS)";
else
info_output << "(no ABS)";
info_output << ": " << ConvertToFeet((stopend-stopstart).length()) << " ft" << std::endl;
}