const Bezier * AiCarStandard::GetCurrentPatch(const CarDynamics * c)
{
const Bezier *curr_patch = c->GetWheelContact(WheelPosition(0)).GetPatch();
if (!curr_patch)
{
// let's try the other wheel
curr_patch = c->GetWheelContact(WheelPosition(1)).GetPatch();
if (!curr_patch) return NULL;
}
return curr_patch;
}
void AiCarStandard::CalcMu()
{
const float tire_load = 0.25 * GRAVITY / car->GetInvMass();
float long_friction = 0.0;
float lat_friction = 0.0;
for (int i = 0; i < 4; i++)
{
long_friction += car->GetTire(WheelPosition(i)).getMaxFx(tire_load);
lat_friction += car->GetTire(WheelPosition(i)).getMaxFy(tire_load, 0.0);
}
float long_mu = FRICTION_FACTOR_LONG * long_friction * car->GetInvMass() / GRAVITY;
float lat_mu = FRICTION_FACTOR_LAT * lat_friction * car->GetInvMass() / GRAVITY;
if (!std::isnan(long_mu)) longitude_mu = long_mu;
if (!std::isnan(lat_mu)) lateral_mu = lat_mu;
}
void CarSound::Update(const CarDynamics & dynamics, float dt)
{
if (!psound) return;
Vec3 pos_car = ToMathVector<float>(dynamics.GetPosition());
Vec3 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
const float rpm = dynamics.GetTachoRPM();
const float throttle = dynamics.GetEngine().GetThrottle();
float total_gain = 0.0;
std::vector<std::pair<size_t, float> > gainlist;
gainlist.reserve(enginesounds.size());
for (auto & info : enginesounds)
{
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 (const auto & sound_gain : gainlist)
{
float gain;
if (total_gain == 0.0)
{
gain = 0.0;
}
else if (enginesounds.size() == 1 && enginesounds.back().power == EngineSoundInfo::BOTH)
{
gain = sound_gain.second;
}
else
{
gain = sound_gain.second / total_gain;
}
psound->SetSourceGain(sound_gain.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 = dynamics.GetTireSquealAmount(WheelPosition(i));
float maxgain = 0.3;
float pitchvariation = 0.4;
unsigned sound_active = 0;
const TrackSurface & surface = dynamics.GetWheelContact(WheelPosition(i)).GetSurface();
if (surface.type == TrackSurface::ASPHALT)
{
sound_active = tiresqueal[i];
}
else if (surface.type == TrackSurface::GRASS)
{
sound_active = grasssound[i];
maxgain = 0.4; // up the grass sound volume a little
}
else if (surface.type == TrackSurface::GRAVEL)
{
sound_active = gravelsound[i];
maxgain = 0.4;
}
else if (surface.type == TrackSurface::CONCRETE)
{
sound_active = tiresqueal[i];
maxgain = 0.3;
pitchvariation = 0.25;
}
else if (surface.type == TrackSurface::SAND)
{
sound_active = grasssound[i];
maxgain = 0.25; // quieter for sand
pitchvariation = 0.25;
}
else
{
sound_active = tiresqueal[i];
maxgain = 0.0;
}
btVector3 pos_wheel = dynamics.GetWheelPosition(WheelPosition(i));
btVector3 vel_wheel = dynamics.GetWheelVelocity(WheelPosition(i));
float pitch = (vel_wheel.length() - 5.0) * 0.1;
pitch = clamp(pitch, 0.0f, 1.0f);
pitch = 1.0 - pitch;
pitch *= pitchvariation;
pitch = pitch + (1.0 - pitchvariation);
pitch = clamp(pitch, 0.1f, 4.0f);
psound->SetSourcePosition(sound_active, pos_wheel[0], pos_wheel[1], pos_wheel[2]);
psound->SetSourcePitch(sound_active, pitch);
psound->SetSourceGain(sound_active, squeal * maxgain);
}
// update road noise sound
{
float gain = dynamics.GetVelocity().length();
gain *= 0.02;
gain *= gain;
if (gain > 1) gain = 1;
psound->SetSourceGain(roadnoise, gain);
}
/* fixme
// 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(dynamics.GetSpeed(), dt);
float crashdecel = crashdetection.GetMaxDecel();
if (crashdecel > 0)
{
const float mingainat = 200;
const float maxgainat = 2000;
float gain = (crashdecel - mingainat) / (maxgainat - mingainat);
gain = clamp(gain, 0.1f, 1.0f);
if (!psound->GetSourcePlaying(crashsound))
{
psound->ResetSource(crashsound);
psound->SetSourceGain(crashsound, gain);
}
}
// update interior sounds
if (!interior) return;
// update gear sound
if (gearsound_check != dynamics.GetTransmission().GetGear())
{
float gain = 0.0;
if (rpm > 0.0)
gain = dynamics.GetEngine().GetRPMLimit() / rpm;
gain = clamp(gain, 0.25f, 0.50f);
if (!psound->GetSourcePlaying(gearsound))
{
psound->ResetSource(gearsound);
psound->SetSourceGain(gearsound, gain);
}
gearsound_check = dynamics.GetTransmission().GetGear();
}
/* fixme
// brake sound
if (inputs[CarInput::BRAKE] > 0 && !brakesound_check)
{
// disable brake sound, sounds wierd
if (false)//!psound->GetSourcePlaying(brakesound))
{
psound->ResetSource(brakesound);
psound->SetSourceGain(brakesound, 0.5);
}
brakesound_check = true;
}
if (inputs[CarInput::BRAKE] <= 0)
brakesound_check = false;
// handbrake sound
if (inputs[CarInput::HANDBRAKE] > 0 && !handbrakesound_check)
{
if (!psound->GetSourcePlaying(handbrakesound))
{
psound->ResetSource(handbrakesound);
psound->SetSourceGain(handbrakesound, 0.5);
}
handbrakesound_check = true;
}
if (inputs[CarInput::HANDBRAKE] <= 0)
handbrakesound_check = false;
*/
}
void PerformanceTesting::TestStoppingDistance(bool abs, std::ostream & info_output, std::ostream & error_output)
{
info_output << "Testing stopping distance" << std::endl;
float maxtime = 300.0;
float t = 0.;
float dt = 1/90.0;
int i = 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
ResetCar();
car.SetABS(abs);
while (t < maxtime)
{
if (accelerating)
{
carinput[CarInput::THROTTLE] = 1.0f;
carinput[CarInput::BRAKE] = 0.0f;
}
else
{
carinput[CarInput::THROTTLE] = 0.0f;
carinput[CarInput::BRAKE] = 1.0f;
}
car.Update(carinput);
world.update(dt);
float car_speed = car.GetSpeed();
if (car_speed >= brakestartspeed && accelerating) //stop accelerating and hit the brakes
{
accelerating = false;
stopstart = car.GetWheelPosition(WheelPosition(0));
//std::cout << "hitting the brakes at " << t << ", " << car_speed << std::endl;
}
if (!accelerating && car_speed < stopthreshold)
{
break;
}
if (!car.GetEngine().GetCombustion())
{
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.GetWheelPosition(WheelPosition(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;
}
void PerformanceTesting::TestStoppingDistance(bool abs, std::ostream & info_output, std::ostream & error_output)
{
info_output << "Testing stopping distance" << std::endl;
float maxtime = 300;
float t = 0.;
float dt = 1/90.0;
int i = 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)
// wheel lockup speeds during braking
float front_lockup_speed = 0.0f;
float rear_lockup_speed = 0.0f;
bool accelerating = true; //switches to false once 60 mph is reached
ResetCar();
car.SetABS(abs);
while (t < maxtime)
{
if (accelerating && car.GetTransmission().GetGear() == 1 &&
car.GetEngine().GetRPM() > 0.8f * car.GetEngine().GetRedline())
{
carinput[CarInput::BRAKE] = 0;
carinput[CarInput::CLUTCH] = 0;
}
car.Update(carinput);
world.update(dt);
float car_speed = car.GetSpeed();
if (car_speed >= brakestartspeed && accelerating) //stop accelerating and hit the brakes
{
stopstart = car.GetWheelPosition(WheelPosition(0));
carinput[CarInput::THROTTLE] = 0;
carinput[CarInput::BRAKE] = 1;
accelerating = false;
//info_output << "hitting the brakes at " << t << ", " << car_speed << std::endl;
}
if (!accelerating && car_speed < stopthreshold)
{
break;
}
if (!accelerating)
{
if (!(front_lockup_speed > 0) && car.GetWheel(WheelPosition(0)).GetRPM() < 0.001f)
{
front_lockup_speed = car_speed;
}
if (!(rear_lockup_speed > 0) && car.GetWheel(WheelPosition(3)).GetRPM() < 0.001f)
{
rear_lockup_speed = car_speed;
}
}
if (t > 0 && !car.GetEngine().GetCombustion())
{
error_output << "Car stalled during launch, t=" << t << std::endl;
}
if (i % (int)(1/dt) == 0) //every second
{
//info_output << t
// << ", " << car_speed
// << ", " << car.GetWheel(WheelPosition(0)).GetAngularVelocity()
// << ", " << car.GetBrake(WheelPosition(0)).GetBrakeFactor()
// << std::endl;
}
t += dt;
i++;
}
btVector3 stopend = car.GetWheelPosition(WheelPosition(0));
info_output << "60-0 stopping distance ";
if (abs)
info_output << "(ABS)";
else
info_output << "(no ABS)";
info_output << ": " << ConvertToFeet((stopend-stopstart).length()) << " ft\n"
<< "Wheel lockup speed " << ConvertToMPH(front_lockup_speed)
<< ", " << ConvertToMPH(rear_lockup_speed) << std::endl;
}
