static ALvoid EchoUpdate(ALeffectState *effect, ALCcontext *Context, const ALeffectslot *Slot)
{
ALechoState *state = (ALechoState*)effect;
ALCdevice *Device = Context->Device;
ALuint frequency = Device->Frequency;
ALfloat lrpan, cw, g, gain;
ALuint i;
state->Tap[0].delay = (ALuint)(Slot->effect.Echo.Delay * frequency) + 1;
state->Tap[1].delay = (ALuint)(Slot->effect.Echo.LRDelay * frequency);
state->Tap[1].delay += state->Tap[0].delay;
lrpan = Slot->effect.Echo.Spread*0.5f + 0.5f;
state->GainL = aluSqrt( lrpan);
state->GainR = aluSqrt(1.0f-lrpan);
state->FeedGain = Slot->effect.Echo.Feedback;
cw = cos(2.0*M_PI * LOWPASSFREQCUTOFF / frequency);
g = 1.0f - Slot->effect.Echo.Damping;
state->iirFilter.coeff = lpCoeffCalc(g, cw);
gain = Slot->Gain;
for(i = 0;i < MAXCHANNELS;i++)
state->Gain[i] = 0.0f;
for(i = 0;i < Device->NumChan;i++)
{
enum Channel chan = Device->Speaker2Chan[i];
state->Gain[chan] = gain;
}
}
static ALvoid EchoUpdate(ALeffectState *effect, ALCdevice *Device, const ALeffectslot *Slot)
{
ALechoState *state = (ALechoState*)effect;
ALuint frequency = Device->Frequency;
ALfloat lrpan, cw, g, gain;
ALfloat dirGain;
ALuint i;
state->Tap[0].delay = fastf2u(Slot->effect.Echo.Delay * frequency) + 1;
state->Tap[1].delay = fastf2u(Slot->effect.Echo.LRDelay * frequency);
state->Tap[1].delay += state->Tap[0].delay;
lrpan = Slot->effect.Echo.Spread;
state->FeedGain = Slot->effect.Echo.Feedback;
cw = aluCos(F_PI*2.0f * LOWPASSFREQREF / frequency);
g = 1.0f - Slot->effect.Echo.Damping;
state->iirFilter.coeff = lpCoeffCalc(g, cw);
gain = Slot->Gain;
for(i = 0;i < MAXCHANNELS;i++)
{
state->Gain[0][i] = 0.0f;
state->Gain[1][i] = 0.0f;
}
dirGain = aluFabs(lrpan);
/* First tap panning */
ComputeAngleGains(Device, aluAtan2(-lrpan, 0.0f), (1.0f-dirGain)*F_PI, gain, state->Gain[0]);
/* Second tap panning */
ComputeAngleGains(Device, aluAtan2(+lrpan, 0.0f), (1.0f-dirGain)*F_PI, gain, state->Gain[1]);
}
// Calculate the coefficient for a HF (and eventually LF) decay damping
// filter.
static __inline ALfloat CalcDampingCoeff( ALfloat hfRatio, ALfloat length, ALfloat decayTime, ALfloat decayCoeff, ALfloat cw )
{
ALfloat coeff, g;
// Eventually this should boost the high frequencies when the ratio
// exceeds 1.
coeff = 0.0f;
if ( hfRatio < 1.0f )
{
// Calculate the low-pass coefficient by dividing the HF decay
// coefficient by the full decay coefficient.
g = CalcDecayCoeff( length, decayTime * hfRatio ) / decayCoeff;
// Damping is done with a 1-pole filter, so g needs to be squared.
g *= g;
coeff = lpCoeffCalc( g, cw );
// Very low decay times will produce minimal output, so apply an
// upper bound to the coefficient.
coeff = __min( coeff, 0.98f );
}
return coeff;
}
// This updates the EAX reverb state. This is called any time the EAX reverb
// effect is loaded into a slot.
static ALvoid EAXVerbUpdate( ALeffectState* effect, ALCcontext* Context, const ALeffect* Effect )
{
ALverbState* State = ( ALverbState* )effect;
ALuint frequency = Context->Device->Frequency;
ALfloat cw, x, y, hfRatio;
// Calculate the master low-pass filter (from the master effect HF gain).
cw = CalcI3DL2HFreq( Effect->Reverb.HFReference, frequency );
// This is done with 2 chained 1-pole filters, so no need to square g.
State->LpFilter.coeff = lpCoeffCalc( Effect->Reverb.GainHF, cw );
// Update the modulator line.
UpdateModulator( Effect->Reverb.ModulationTime,
Effect->Reverb.ModulationDepth, frequency, State );
// Update the initial effect delay.
UpdateDelayLine( Effect->Reverb.ReflectionsDelay,
Effect->Reverb.LateReverbDelay, frequency, State );
// Update the early lines.
UpdateEarlyLines( Effect->Reverb.Gain, Effect->Reverb.ReflectionsGain,
Effect->Reverb.LateReverbDelay, State );
// Update the decorrelator.
UpdateDecorrelator( Effect->Reverb.Density, frequency, State );
// Get the mixing matrix coefficients (x and y).
CalcMatrixCoeffs( Effect->Reverb.Diffusion, &x, &y );
// Then divide x into y to simplify the matrix calculation.
State->Late.MixCoeff = y / x;
// If the HF limit parameter is flagged, calculate an appropriate limit
// based on the air absorption parameter.
hfRatio = Effect->Reverb.DecayHFRatio;
if ( Effect->Reverb.DecayHFLimit && Effect->Reverb.AirAbsorptionGainHF < 1.0f )
hfRatio = CalcLimitedHfRatio( hfRatio, Effect->Reverb.AirAbsorptionGainHF,
Effect->Reverb.DecayTime );
// Update the late lines.
UpdateLateLines( Effect->Reverb.Gain, Effect->Reverb.LateReverbGain,
x, Effect->Reverb.Density, Effect->Reverb.DecayTime,
Effect->Reverb.Diffusion, hfRatio, cw, frequency, State );
// Update the echo line.
UpdateEchoLine( Effect->Reverb.Gain, Effect->Reverb.LateReverbGain,
Effect->Reverb.EchoTime, Effect->Reverb.DecayTime,
Effect->Reverb.Diffusion, Effect->Reverb.EchoDepth,
hfRatio, cw, frequency, State );
// Update early and late 3D panning.
Update3DPanning( Effect->Reverb.ReflectionsPan, Effect->Reverb.LateReverbPan,
Context->Device->PanningLUT, State );
}
static float CalcDampingCoeff(float hfRatio, float length, float decayTime, float decayCoeff, float cw)
{
float coeff, g;
coeff = 0.0f;
if (hfRatio < 1.0f)
{
/* Calculate the low-pass coefficient by dividing the HF decay
* coefficient by the full decay coefficient. */
g = CalcDecayCoeff(length, decayTime * hfRatio) / decayCoeff;
/* Damping is done with a 1-pole filter, so g needs to be squared. */
g *= g;
coeff = lpCoeffCalc(g, cw);
/* Very low decay times will produce minimal output, so apply an
* upper bound to the coefficient. */
if (coeff > 0.98f) coeff = 0.98f;
}
return coeff;
}
// This updates the EAX reverb state. This is called any time the EAX reverb
// effect is loaded into a slot.
static ALvoid ReverbUpdate(ALeffectState *effect, ALCcontext *Context, const ALeffectslot *Slot)
{
ALverbState *State = (ALverbState*)effect;
ALuint frequency = Context->Device->Frequency;
ALboolean isEAX = AL_FALSE;
ALfloat cw, x, y, hfRatio;
if(Slot->effect.type == AL_EFFECT_EAXREVERB && !EmulateEAXReverb)
{
State->state.Process = EAXVerbProcess;
isEAX = AL_TRUE;
}
else if(Slot->effect.type == AL_EFFECT_REVERB || EmulateEAXReverb)
{
State->state.Process = VerbProcess;
isEAX = AL_FALSE;
}
// Calculate the master low-pass filter (from the master effect HF gain).
cw = CalcI3DL2HFreq(Slot->effect.Params.Reverb.HFReference, frequency);
// This is done with 2 chained 1-pole filters, so no need to square g.
State->LpFilter.coeff = lpCoeffCalc(Slot->effect.Params.Reverb.GainHF, cw);
if(isEAX)
{
// Update the modulator line.
UpdateModulator(Slot->effect.Params.Reverb.ModulationTime,
Slot->effect.Params.Reverb.ModulationDepth,
frequency, State);
}
// Update the initial effect delay.
UpdateDelayLine(Slot->effect.Params.Reverb.ReflectionsDelay,
Slot->effect.Params.Reverb.LateReverbDelay,
frequency, State);
// Update the early lines.
UpdateEarlyLines(Slot->effect.Params.Reverb.Gain,
Slot->effect.Params.Reverb.ReflectionsGain,
Slot->effect.Params.Reverb.LateReverbDelay, State);
// Update the decorrelator.
UpdateDecorrelator(Slot->effect.Params.Reverb.Density, frequency, State);
// Get the mixing matrix coefficients (x and y).
CalcMatrixCoeffs(Slot->effect.Params.Reverb.Diffusion, &x, &y);
// Then divide x into y to simplify the matrix calculation.
State->Late.MixCoeff = y / x;
// If the HF limit parameter is flagged, calculate an appropriate limit
// based on the air absorption parameter.
hfRatio = Slot->effect.Params.Reverb.DecayHFRatio;
if(Slot->effect.Params.Reverb.DecayHFLimit &&
Slot->effect.Params.Reverb.AirAbsorptionGainHF < 1.0f)
hfRatio = CalcLimitedHfRatio(hfRatio,
Slot->effect.Params.Reverb.AirAbsorptionGainHF,
Slot->effect.Params.Reverb.DecayTime);
// Update the late lines.
UpdateLateLines(Slot->effect.Params.Reverb.Gain, Slot->effect.Params.Reverb.LateReverbGain,
x, Slot->effect.Params.Reverb.Density, Slot->effect.Params.Reverb.DecayTime,
Slot->effect.Params.Reverb.Diffusion, hfRatio, cw, frequency, State);
if(isEAX)
{
// Update the echo line.
UpdateEchoLine(Slot->effect.Params.Reverb.Gain, Slot->effect.Params.Reverb.LateReverbGain,
Slot->effect.Params.Reverb.EchoTime, Slot->effect.Params.Reverb.DecayTime,
Slot->effect.Params.Reverb.Diffusion, Slot->effect.Params.Reverb.EchoDepth,
hfRatio, cw, frequency, State);
// Update early and late 3D panning.
Update3DPanning(Context->Device, Slot->effect.Params.Reverb.ReflectionsPan,
Slot->effect.Params.Reverb.LateReverbPan, Slot->Gain, State);
}
else
{
ALCdevice *Device = Context->Device;
ALfloat gain = Slot->Gain;
ALuint index;
/* Update channel gains */
gain *= aluSqrt(2.0f/Device->NumChan) * ReverbBoost;
for(index = 0;index < MAXCHANNELS;index++)
State->Gain[index] = 0.0f;
for(index = 0;index < Device->NumChan;index++)
{
enum Channel chan = Device->Speaker2Chan[index];
State->Gain[chan] = gain;
}
}
}
