ref: bc99f48aca15efd07cb81853172b95e83076314f
dir: /LEAF/Src/leaf-physical.c/
/*==============================================================================
leaf-string.c
Created: 30 Nov 2018 10:41:42am
Author: airship
==============================================================================*/
#if _WIN32 || _WIN64
#include "..\Inc\leaf-physical.h"
#else
#include "../Inc/leaf-physical.h"
#endif
/* ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ tPluck ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ */
void tPluck_init (tPluck* const pl, float lowestFrequency)
{
_tPluck* p = *pl = (_tPluck*) leaf_alloc(sizeof(_tPluck));
if ( lowestFrequency <= 0.0f ) lowestFrequency = 10.0f;
tNoise_init(&p->noise, WhiteNoise);
tOnePole_init(&p->pickFilter, 0.0f);
tOneZero_init(&p->loopFilter, 0.0f);
tAllpassDelay_init(&p->delayLine, 0.0f, leaf.sampleRate * 2);
tPluck_setFrequency(pl, 220.0f);
}
void tPluck_free (tPluck* const pl)
{
_tPluck* p = *pl;
tNoise_free(&p->noise);
tOnePole_free(&p->pickFilter);
tOneZero_free(&p->loopFilter);
tAllpassDelay_free(&p->delayLine);
leaf_free(p);
}
float tPluck_getLastOut (tPluck* const pl)
{
_tPluck* p = *pl;
return p->lastOut;
}
float tPluck_tick (tPluck* const pl)
{
_tPluck* p = *pl;
return (p->lastOut = 3.0f * tAllpassDelay_tick(&p->delayLine, tOneZero_tick(&p->loopFilter, tAllpassDelay_getLastOut(&p->delayLine) * p->loopGain ) ));
}
void tPluck_pluck (tPluck* const pl, float amplitude)
{
_tPluck* p = *pl;
if ( amplitude < 0.0f) amplitude = 0.0f;
else if (amplitude > 1.0f) amplitude = 1.0f;
tOnePole_setPole(&p->pickFilter, 0.999f - (amplitude * 0.15f));
tOnePole_setGain(&p->pickFilter, amplitude * 0.5f );
// Fill delay with noise additively with current contents.
for ( uint32_t i = 0; i < (uint32_t)tAllpassDelay_getDelay(&p->delayLine); i++ )
tAllpassDelay_tick(&p->delayLine, 0.6f * tAllpassDelay_getLastOut(&p->delayLine) + tOnePole_tick(&p->pickFilter, tNoise_tick(&p->noise) ) );
}
// Start a note with the given frequency and amplitude.;
void tPluck_noteOn (tPluck* const pl, float frequency, float amplitude )
{
_tPluck* p = *pl;
p->lastFreq = frequency;
tPluck_setFrequency( pl, frequency );
tPluck_pluck( pl, amplitude );
}
// Stop a note with the given amplitude (speed of decay).
void tPluck_noteOff (tPluck* const pl, float amplitude )
{
_tPluck* p = *pl;
if ( amplitude < 0.0f) amplitude = 0.0f;
else if (amplitude > 1.0f) amplitude = 1.0f;
p->loopGain = 1.0f - amplitude;
}
// Set instrument parameters for a particular frequency.
void tPluck_setFrequency (tPluck* const pl, float frequency )
{
_tPluck* p = *pl;
if ( frequency <= 0.0f ) frequency = 0.001f;
// Delay = length - filter delay.
float delay = ( leaf.sampleRate / frequency ) - tOneZero_getPhaseDelay(&p->loopFilter, frequency );
tAllpassDelay_setDelay(&p->delayLine, delay );
p->loopGain = 0.99f + (frequency * 0.000005f);
if ( p->loopGain >= 0.999f ) p->loopGain = 0.999f;
}
// Perform the control change specified by \e number and \e value (0.0 - 128.0).
void tPluck_controlChange (tPluck* const pl, int number, float value)
{
return;
}
void tPluckSampleRateChanged(tPluck* const pl)
{
_tPluck* p = *pl;
tPluck_setFrequency(pl, p->lastFreq);
}
/* ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ tKarplusStrong ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ */
void tKarplusStrong_init (tKarplusStrong* const pl, float lowestFrequency)
{
_tKarplusStrong* p = *pl = (_tKarplusStrong*) leaf_alloc(sizeof(_tKarplusStrong));
if ( lowestFrequency <= 0.0f ) lowestFrequency = 8.0f;
tAllpassDelay_init(&p->delayLine, 0.0f, leaf.sampleRate * 2);
tLinearDelay_init(&p->combDelay, 0.0f, leaf.sampleRate * 2);
tOneZero_init(&p->filter, 0.0f);
tNoise_init(&p->noise, WhiteNoise);
for (int i = 0; i < 4; i++)
{
tBiQuad_init(&p->biquad[i]);
}
p->pluckAmplitude = 0.3f;
p->pickupPosition = 0.4f;
p->stretching = 0.9999f;
p->baseLoopGain = 0.995f;
p->loopGain = 0.999f;
tKarplusStrong_setFrequency( pl, 220.0f );
}
void tKarplusStrong_free (tKarplusStrong* const pl)
{
_tKarplusStrong* p = *pl;
tAllpassDelay_free(&p->delayLine);
tLinearDelay_free(&p->combDelay);
tOneZero_free(&p->filter);
tNoise_free(&p->noise);
for (int i = 0; i < 4; i++)
{
tBiQuad_free(&p->biquad[i]);
}
leaf_free(p);
}
float tKarplusStrong_getLastOut (tKarplusStrong* const pl)
{
_tKarplusStrong* p = *pl;
return p->lastOut;
}
float tKarplusStrong_tick (tKarplusStrong* const pl)
{
_tKarplusStrong* p = *pl;
float temp = tAllpassDelay_getLastOut(&p->delayLine) * p->loopGain;
// Calculate allpass stretching.
for (int i=0; i<4; i++) temp = tBiQuad_tick(&p->biquad[i],temp);
// Moving average filter.
temp = tOneZero_tick(&p->filter, temp);
float out = tAllpassDelay_tick(&p->delayLine, temp);
out = out - tLinearDelay_tick(&p->combDelay, out);
p->lastOut = out;
return p->lastOut;
}
void tKarplusStrong_pluck (tKarplusStrong* const pl, float amplitude)
{
_tKarplusStrong* p = *pl;
if ( amplitude < 0.0f) amplitude = 0.0f;
else if (amplitude > 1.0f) amplitude = 1.0f;
p->pluckAmplitude = amplitude;
for ( uint32_t i=0; i < (uint32_t)tAllpassDelay_getDelay(&p->delayLine); i++ )
{
// Fill delay with noise additively with current contents.
tAllpassDelay_tick(&p->delayLine, (tAllpassDelay_getLastOut(&p->delayLine) * 0.6f) + 0.4f * tNoise_tick(&p->noise) * p->pluckAmplitude );
//delayLine_.tick( combDelay_.tick((delayLine_.lastOut() * 0.6) + 0.4 * noise->tick() * pluckAmplitude_) );
}
}
// Start a note with the given frequency and amplitude.;
void tKarplusStrong_noteOn (tKarplusStrong* const pl, float frequency, float amplitude )
{
tKarplusStrong_setFrequency( pl, frequency );
tKarplusStrong_pluck( pl, amplitude );
}
// Stop a note with the given amplitude (speed of decay).
void tKarplusStrong_noteOff (tKarplusStrong* const pl, float amplitude )
{
_tKarplusStrong* p = *pl;
if ( amplitude < 0.0f) amplitude = 0.0f;
else if (amplitude > 1.0f) amplitude = 1.0f;
p->loopGain = 1.0f - amplitude;
}
// Set instrument parameters for a particular frequency.
void tKarplusStrong_setFrequency (tKarplusStrong* const pl, float frequency )
{
_tKarplusStrong* p = *pl;
if ( frequency <= 0.0f ) frequency = 0.001f;
p->lastFrequency = frequency;
p->lastLength = leaf.sampleRate / p->lastFrequency;
float delay = p->lastLength - 0.5f;
tAllpassDelay_setDelay(&p->delayLine, delay);
// MAYBE MODIFY LOOP GAINS
p->loopGain = p->baseLoopGain + (frequency * 0.000005f);
if (p->loopGain >= 1.0f) p->loopGain = 0.99999f;
tKarplusStrong_setStretch(pl, p->stretching);
tLinearDelay_setDelay(&p->combDelay, 0.5f * p->pickupPosition * p->lastLength );
}
// Set the stretch "factor" of the string (0.0 - 1.0).
void tKarplusStrong_setStretch (tKarplusStrong* const pl, float stretch )
{
_tKarplusStrong* p = *pl;
p->stretching = stretch;
float coefficient;
float freq = p->lastFrequency * 2.0f;
float dFreq = ( (0.5f * leaf.sampleRate) - freq ) * 0.25f;
float temp = 0.5f + (stretch * 0.5f);
if ( temp > 0.9999f ) temp = 0.9999f;
for ( int i=0; i<4; i++ )
{
coefficient = temp * temp;
tBiQuad_setA2(&p->biquad[i], coefficient);
tBiQuad_setB0(&p->biquad[i], coefficient);
tBiQuad_setB2(&p->biquad[i], 1.0f);
coefficient = -2.0f * temp * cos(TWO_PI * freq / leaf.sampleRate);
tBiQuad_setA1(&p->biquad[i], coefficient);
tBiQuad_setB1(&p->biquad[i], coefficient);
freq += dFreq;
}
}
// Set the pluck or "excitation" position along the string (0.0 - 1.0).
void tKarplusStrong_setPickupPosition (tKarplusStrong* const pl, float position )
{
_tKarplusStrong* p = *pl;
if (position < 0.0f) p->pickupPosition = 0.0f;
else if (position <= 1.0f) p->pickupPosition = position;
else p->pickupPosition = 1.0f;
tLinearDelay_setDelay(&p->combDelay, 0.5f * p->pickupPosition * p->lastLength);
}
// Set the base loop gain.
void tKarplusStrong_setBaseLoopGain (tKarplusStrong* const pl, float aGain )
{
_tKarplusStrong* p = *pl;
p->baseLoopGain = aGain;
p->loopGain = p->baseLoopGain + (p->lastFrequency * 0.000005f);
if ( p->loopGain > 0.99999f ) p->loopGain = 0.99999f;
}
// Perform the control change specified by \e number and \e value (0.0 - 128.0).
void tKarplusStrong_controlChange (tKarplusStrong* const pl, SKControlType type, float value)
{
if ( value < 0.0f ) value = 0.0f;
else if (value > 128.0f) value = 128.0f;
float normalizedValue = value * INV_128;
if (type == SKPickPosition) // 4
tKarplusStrong_setPickupPosition( pl, normalizedValue );
else if (type == SKStringDamping) // 11
tKarplusStrong_setBaseLoopGain( pl, 0.97f + (normalizedValue * 0.03f) );
else if (type == SKDetune) // 1
tKarplusStrong_setStretch( pl, 0.91f + (0.09f * (1.0f - normalizedValue)) );
}
void tKarplusStrongSampleRateChanged (tKarplusStrong* const pl)
{
_tKarplusStrong* p = *pl;
tKarplusStrong_setFrequency(pl, p->lastFrequency);
tKarplusStrong_setStretch(pl, p->stretching);
}
/* Simple Living String*/
void tSimpleLivingString_init(tSimpleLivingString* const pl, float freq, float dampFreq, float decay, float targetLev, float levSmoothFactor, float levStrength, int levMode)
{
_tSimpleLivingString* p = *pl = (_tSimpleLivingString*) leaf_alloc(sizeof(_tSimpleLivingString));
p->curr=0.0f;
tExpSmooth_init(&p->wlSmooth, leaf.sampleRate/freq, 0.01); // smoother for string wavelength (not freq, to avoid expensive divisions)
tSimpleLivingString_setFreq(pl, freq);
tLinearDelay_init(&p->delayLine,p->waveLengthInSamples, 2400);
tOnePole_init(&p->bridgeFilter, dampFreq);
tHighpass_init(&p->DCblocker,13);
p->decay=decay;
tFeedbackLeveler_init(&p->fbLev, targetLev, levSmoothFactor, levStrength, levMode);
p->levMode=levMode;
}
void tSimpleLivingString_free(tSimpleLivingString* const pl)
{
_tSimpleLivingString* p = *pl;
tExpSmooth_free(&p->wlSmooth);
tLinearDelay_free(&p->delayLine);
tOnePole_free(&p->bridgeFilter);
tHighpass_free(&p->DCblocker);
tFeedbackLeveler_free(&p->fbLev);
leaf_free(p);
}
void tSimpleLivingString_setFreq(tSimpleLivingString* const pl, float freq)
{
_tSimpleLivingString* p = *pl;
if (freq<20) freq=20;
else if (freq>10000) freq=10000;
p->waveLengthInSamples = leaf.sampleRate/freq;
tExpSmooth_setDest(&p->wlSmooth, p->waveLengthInSamples);
}
void tSimpleLivingString_setWaveLength(tSimpleLivingString* const pl, float waveLength)
{
_tSimpleLivingString* p = *pl;
if (waveLength<4.8) waveLength=4.8;
else if (waveLength>2400) waveLength=2400;
p->waveLengthInSamples = waveLength;
tExpSmooth_setDest(&p->wlSmooth, p->waveLengthInSamples);
}
void tSimpleLivingString_setDampFreq(tSimpleLivingString* const pl, float dampFreq)
{
_tSimpleLivingString* p = *pl;
tOnePole_setFreq(&p->bridgeFilter, dampFreq);
}
void tSimpleLivingString_setDecay(tSimpleLivingString* const pl, float decay)
{
_tSimpleLivingString* p = *pl;
p->decay=decay;
}
void tSimpleLivingString_setTargetLev(tSimpleLivingString* const pl, float targetLev)
{
_tSimpleLivingString* p = *pl;
tFeedbackLeveler_setTargetLevel(&p->fbLev, targetLev);
}
void tSimpleLivingString_setLevSmoothFactor(tSimpleLivingString* const pl, float levSmoothFactor)
{
_tSimpleLivingString* p = *pl;
tFeedbackLeveler_setFactor(&p->fbLev, levSmoothFactor);
}
void tSimpleLivingString_setLevStrength(tSimpleLivingString* const pl, float levStrength)
{
_tSimpleLivingString* p = *pl;
tFeedbackLeveler_setStrength(&p->fbLev, levStrength);
}
void tSimpleLivingString_setLevMode(tSimpleLivingString* const pl, int levMode)
{
_tSimpleLivingString* p = *pl;
tFeedbackLeveler_setMode(&p->fbLev, levMode);
p->levMode=levMode;
}
float tSimpleLivingString_tick(tSimpleLivingString* const pl, float input)
{
_tSimpleLivingString* p = *pl;
float stringOut=tOnePole_tick(&p->bridgeFilter,tLinearDelay_tickOut(&p->delayLine));
float stringInput=tHighpass_tick(&p->DCblocker, tFeedbackLeveler_tick(&p->fbLev, (p->levMode==0?p->decay*stringOut:stringOut)+input));
tLinearDelay_tickIn(&p->delayLine, stringInput);
tLinearDelay_setDelay(&p->delayLine, tExpSmooth_tick(&p->wlSmooth));
p->curr = stringOut;
return p->curr;
}
float tSimpleLivingString_sample(tSimpleLivingString* const pl)
{
_tSimpleLivingString* p = *pl;
return p->curr;
}
/* Living String*/
void tLivingString_init(tLivingString* const pl, float freq, float pickPos, float prepIndex, float dampFreq, float decay, float targetLev, float levSmoothFactor, float levStrength, int levMode)
{
_tLivingString* p = *pl = (_tLivingString*) leaf_alloc(sizeof(_tLivingString));
p->curr=0.0f;
tExpSmooth_init(&p->wlSmooth, leaf.sampleRate/freq, 0.01); // smoother for string wavelength (not freq, to avoid expensive divisions)
tLivingString_setFreq(pl, freq);
p->freq = freq;
tExpSmooth_init(&p->ppSmooth, pickPos, 0.01); // smoother for pick position
tLivingString_setPickPos(pl, pickPos);
p->prepIndex=prepIndex;
tLinearDelay_init(&p->delLF,p->waveLengthInSamples, 2400);
tLinearDelay_init(&p->delUF,p->waveLengthInSamples, 2400);
tLinearDelay_init(&p->delUB,p->waveLengthInSamples, 2400);
tLinearDelay_init(&p->delLB,p->waveLengthInSamples, 2400);
p->dampFreq = dampFreq;
tOnePole_init(&p->bridgeFilter, dampFreq);
tOnePole_init(&p->nutFilter, dampFreq);
tOnePole_init(&p->prepFilterU, dampFreq);
tOnePole_init(&p->prepFilterL, dampFreq);
tHighpass_init(&p->DCblockerU,13);
tHighpass_init(&p->DCblockerL,13);
p->decay=decay;
p->prepIndex = prepIndex;
tFeedbackLeveler_init(&p->fbLevU, targetLev, levSmoothFactor, levStrength, levMode);
tFeedbackLeveler_init(&p->fbLevL, targetLev, levSmoothFactor, levStrength, levMode);
p->levMode=levMode;
}
void tLivingString_free(tLivingString* const pl)
{
_tLivingString* p = *pl;
tExpSmooth_free(&p->wlSmooth);
tExpSmooth_free(&p->ppSmooth);
tLinearDelay_free(&p->delLF);
tLinearDelay_free(&p->delUF);
tLinearDelay_free(&p->delUB);
tLinearDelay_free(&p->delLB);
tOnePole_free(&p->bridgeFilter);
tOnePole_free(&p->nutFilter);
tOnePole_free(&p->prepFilterU);
tOnePole_free(&p->prepFilterL);
tHighpass_free(&p->DCblockerU);
tHighpass_free(&p->DCblockerL);
tFeedbackLeveler_free(&p->fbLevU);
tFeedbackLeveler_free(&p->fbLevL);
leaf_free(p);
}
void tLivingString_setFreq(tLivingString* const pl, float freq)
{ // NOTE: It is faster to set wavelength in samples directly
_tLivingString* p = *pl;
if (freq<20) freq=20;
else if (freq>10000) freq=10000;
p->waveLengthInSamples = leaf.sampleRate/freq;
tExpSmooth_setDest(&p->wlSmooth, p->waveLengthInSamples);
}
void tLivingString_setWaveLength(tLivingString* const pl, float waveLength)
{
_tLivingString* p = *pl;
if (waveLength<4.8) waveLength=4.8;
else if (waveLength>2400) waveLength=2400;
p->waveLengthInSamples = waveLength;
tExpSmooth_setDest(&p->wlSmooth, p->waveLengthInSamples);
}
void tLivingString_setPickPos(tLivingString* const pl, float pickPos)
{ // between 0 and 1
_tLivingString* p = *pl;
if (pickPos<0.f) pickPos=0.f;
else if (pickPos>1.f) pickPos=1.f;
p->pickPos = pickPos;
tExpSmooth_setDest(&p->ppSmooth, p->pickPos);
}
void tLivingString_setPrepIndex(tLivingString* const pl, float prepIndex)
{ // between 0 and 1
_tLivingString* p = *pl;
if (prepIndex<0.f) prepIndex=0.f;
else if (prepIndex>1.f) prepIndex=1.f;
p->prepIndex = prepIndex;
}
void tLivingString_setDampFreq(tLivingString* const pl, float dampFreq)
{
_tLivingString* p = *pl;
tOnePole_setFreq(&p->bridgeFilter, dampFreq);
tOnePole_setFreq(&p->nutFilter, dampFreq);
tOnePole_setFreq(&p->prepFilterU, dampFreq);
tOnePole_setFreq(&p->prepFilterL, dampFreq);
}
void tLivingString_setDecay(tLivingString* const pl, float decay)
{
_tLivingString* p = *pl;
p->decay=decay;
}
void tLivingString_setTargetLev(tLivingString* const pl, float targetLev)
{
_tLivingString* p = *pl;
tFeedbackLeveler_setTargetLevel(&p->fbLevU, targetLev);
tFeedbackLeveler_setTargetLevel(&p->fbLevL, targetLev);
}
void tLivingString_setLevSmoothFactor(tLivingString* const pl, float levSmoothFactor)
{
_tLivingString* p = *pl;
tFeedbackLeveler_setFactor(&p->fbLevU, levSmoothFactor);
tFeedbackLeveler_setFactor(&p->fbLevL, levSmoothFactor);
}
void tLivingString_setLevStrength(tLivingString* const pl, float levStrength)
{
_tLivingString* p = *pl;
tFeedbackLeveler_setStrength(&p->fbLevU, levStrength);
tFeedbackLeveler_setStrength(&p->fbLevL, levStrength);
}
void tLivingString_setLevMode(tLivingString* const pl, int levMode)
{
_tLivingString* p = *pl;
tFeedbackLeveler_setMode(&p->fbLevU, levMode);
tFeedbackLeveler_setMode(&p->fbLevL, levMode);
p->levMode=levMode;
}
float tLivingString_tick(tLivingString* const pl, float input)
{
_tLivingString* p = *pl;
// from pickPos upwards=forwards
float fromLF=tLinearDelay_tickOut(&p->delLF);
float fromUF=tLinearDelay_tickOut(&p->delUF);
float fromUB=tLinearDelay_tickOut(&p->delUB);
float fromLB=tLinearDelay_tickOut(&p->delLB);
// into upper half of string, from nut, going backwards
float fromNut=-tFeedbackLeveler_tick(&p->fbLevU, (p->levMode==0?p->decay:1)*tHighpass_tick(&p->DCblockerU, tOnePole_tick(&p->nutFilter, fromUF)));
tLinearDelay_tickIn(&p->delUB, fromNut);
// into lower half of string, from pickpoint, going backwards
float fromLowerPrep=-tOnePole_tick(&p->prepFilterL, fromLF);
float intoLower=p->prepIndex*fromLowerPrep+(1-p->prepIndex)*fromUB+input;
tLinearDelay_tickIn(&p->delLB, intoLower);
// into lower half of string, from bridge
float fromBridge=-tFeedbackLeveler_tick(&p->fbLevL, (p->levMode==0?p->decay:1)*tHighpass_tick(&p->DCblockerL, tOnePole_tick(&p->bridgeFilter, fromLB)));
tLinearDelay_tickIn(&p->delLF, fromBridge);
// into upper half of string, from pickpoint, going forwards/upwards
float fromUpperPrep=-tOnePole_tick(&p->prepFilterU, fromUB);
float intoUpper=p->prepIndex*fromUpperPrep+(1-p->prepIndex)*fromLF+input;
tLinearDelay_tickIn(&p->delUF, intoUpper);
// update all delay lengths
float pickP=tExpSmooth_tick(&p->ppSmooth);
float wLen=tExpSmooth_tick(&p->wlSmooth);
float lowLen=pickP*wLen;
float upLen=(1-pickP)*wLen;
tLinearDelay_setDelay(&p->delLF, lowLen);
tLinearDelay_setDelay(&p->delLB, lowLen);
tLinearDelay_setDelay(&p->delUF, upLen);
tLinearDelay_setDelay(&p->delUB, upLen);
p->curr = fromBridge;
return p->curr;
}
float tLivingString_sample(tLivingString* const pl)
{
_tLivingString* p = *pl;
return p->curr;
}
///Reed Table model
//default values from STK are 0.6 offset and -0.8 slope
void tReedTable_init (tReedTable* const pm, float offset, float slope)
{
_tReedTable* p = *pm = (_tReedTable*) leaf_alloc(sizeof(_tReedTable));
p->offset = offset;
p->slope = slope;
}
void tReedTable_free (tReedTable* const pm)
{
_tReedTable* p = *pm;
leaf_free(p);
}
float tReedTable_tick (tReedTable* const pm, float input)
{
_tReedTable* p = *pm;
// The input is differential pressure across the reed.
float output = p->offset + (p->slope * input);
// If output is > 1, the reed has slammed shut and the
// reflection function value saturates at 1.0.
if ( output > 1.0f) output = 1.0f;
// This is nearly impossible in a physical system, but
// a reflection function value of -1.0 corresponds to
// an open end (and no discontinuity in bore profile).
if ( output < -1.0f) output = -1.0f;
return output;
}
float tReedTable_tanh_tick (tReedTable* const pm, float input)
{
_tReedTable* p = *pm;
// The input is differential pressure across the reed.
float output = p->offset + (p->slope * input);
// If output is > 1, the reed has slammed shut and the
// reflection function value saturates at 1.0.
return tanhf(output);
}
void tReedTable_setOffset (tReedTable* const pm, float offset)
{
_tReedTable* p = *pm;
p->offset = offset;
}
void tReedTable_setSlope (tReedTable* const pm, float slope)
{
_tReedTable* p = *pm;
p->slope = slope;
}