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Version 4.4.0

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Gary Scavone
2013-09-29 23:11:39 +02:00
committed by Stephen Sinclair
parent d199342e86
commit eccd8c9981
287 changed files with 11712 additions and 7676 deletions
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101
src/FormSwep.cpp
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@@ -2,63 +2,83 @@
/*! \class FormSwep
\brief STK sweepable formant filter class.
This public BiQuad filter subclass implements
a formant (resonance) which can be "swept"
over time from one frequency setting to another.
It provides methods for controlling the sweep
rate and target frequency.
This class implements a formant (resonance) which can be "swept"
over time from one frequency setting to another. It provides
methods for controlling the sweep rate and target frequency.
by Perry R. Cook and Gary P. Scavone, 1995 - 2007.
by Perry R. Cook and Gary P. Scavone, 1995 - 2009.
*/
/***************************************************/
#include "FormSwep.h"
#include <cmath>
FormSwep :: FormSwep() : BiQuad()
namespace stk {
FormSwep :: FormSwep( void )
{
frequency_ = (StkFloat) 0.0;
radius_ = (StkFloat) 0.0;
targetGain_ = (StkFloat) 1.0;
targetFrequency_ = (StkFloat) 0.0;
targetRadius_ = (StkFloat) 0.0;
deltaGain_ = (StkFloat) 0.0;
deltaFrequency_ = (StkFloat) 0.0;
deltaRadius_ = (StkFloat) 0.0;
sweepState_ = (StkFloat) 0.0;
sweepRate_ = (StkFloat) 0.002;
frequency_ = 0.0;
radius_ = 0.0;
targetGain_ = 1.0;
targetFrequency_ = 0.0;
targetRadius_ = 0.0;
deltaGain_ = 0.0;
deltaFrequency_ = 0.0;
deltaRadius_ = 0.0;
sweepState_ = 0.0;
sweepRate_ = 0.002;
dirty_ = false;
this->clear();
b_.resize( 3, 0.0 );
a_.resize( 3, 0.0 );
a_[0] = 1.0;
inputs_.resize( 3, 1, 0.0 );
outputs_.resize( 3, 1, 0.0 );
Stk::addSampleRateAlert( this );
}
FormSwep :: ~FormSwep()
{
Stk::removeSampleRateAlert( this );
}
void FormSwep :: setResonance(StkFloat frequency, StkFloat radius)
void FormSwep :: sampleRateChanged( StkFloat newRate, StkFloat oldRate )
{
if ( !ignoreSampleRateChange_ ) {
errorString_ << "FormSwep::sampleRateChanged: you may need to recompute filter coefficients!";
handleError( StkError::WARNING );
}
}
void FormSwep :: setResonance( StkFloat frequency, StkFloat radius )
{
dirty_ = false;
radius_ = radius;
frequency_ = frequency;
BiQuad::setResonance( frequency_, radius_, true );
a_[2] = radius * radius;
a_[1] = -2.0 * radius * cos( TWO_PI * frequency / Stk::sampleRate() );
// Use zeros at +- 1 and normalize the filter peak gain.
b_[0] = 0.5 - 0.5 * a_[2];
b_[1] = 0.0;
b_[2] = -b_[0];
}
void FormSwep :: setStates(StkFloat frequency, StkFloat radius, StkFloat gain)
void FormSwep :: setStates( StkFloat frequency, StkFloat radius, StkFloat gain )
{
dirty_ = false;
if ( frequency_ != frequency || radius_ != radius )
BiQuad::setResonance( frequency, radius, true );
this->setResonance( frequency, radius );
frequency_ = frequency;
radius_ = radius;
gain_ = gain;
targetFrequency_ = frequency;
targetRadius_ = radius;
targetGain_ = gain;
}
void FormSwep :: setTargets(StkFloat frequency, StkFloat radius, StkFloat gain)
void FormSwep :: setTargets( StkFloat frequency, StkFloat radius, StkFloat gain )
{
dirty_ = true;
startFrequency_ = frequency_;
@@ -70,42 +90,21 @@ void FormSwep :: setTargets(StkFloat frequency, StkFloat radius, StkFloat gain)
deltaFrequency_ = frequency - frequency_;
deltaRadius_ = radius - radius_;
deltaGain_ = gain - gain_;
sweepState_ = (StkFloat) 0.0;
sweepState_ = 0.0;
}
void FormSwep :: setSweepRate(StkFloat rate)
void FormSwep :: setSweepRate( StkFloat rate )
{
sweepRate_ = rate;
if ( sweepRate_ > 1.0 ) sweepRate_ = 1.0;
if ( sweepRate_ < 0.0 ) sweepRate_ = 0.0;
}
void FormSwep :: setSweepTime(StkFloat time)
void FormSwep :: setSweepTime( StkFloat time )
{
sweepRate_ = 1.0 / ( time * Stk::sampleRate() );
if ( sweepRate_ > 1.0 ) sweepRate_ = 1.0;
if ( sweepRate_ < 0.0 ) sweepRate_ = 0.0;
}
StkFloat FormSwep :: computeSample( StkFloat input )
{
if (dirty_) {
sweepState_ += sweepRate_;
if ( sweepState_ >= 1.0 ) {
sweepState_ = 1.0;
dirty_ = false;
radius_ = targetRadius_;
frequency_ = targetFrequency_;
gain_ = targetGain_;
}
else {
radius_ = startRadius_ + (deltaRadius_ * sweepState_);
frequency_ = startFrequency_ + (deltaFrequency_ * sweepState_);
gain_ = startGain_ + (deltaGain_ * sweepState_);
}
BiQuad::setResonance( frequency_, radius_, true );
}
return BiQuad::computeSample( input );
}
} // stk namespace