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- /***************************************************/
- /*! \class Bowed
- \brief STK bowed string instrument class.
-
- This class implements a bowed string model, a
- la Smith (1986), after McIntyre, Schumacher,
- Woodhouse (1983).
-
- This is a digital waveguide model, making its
- use possibly subject to patents held by
- Stanford University, Yamaha, and others.
-
- Control Change Numbers:
- - Bow Pressure = 2
- - Bow Position = 4
- - Vibrato Frequency = 11
- - Vibrato Gain = 1
- - Bow Velocity = 100
- - Frequency = 101
- - Volume = 128
-
- by Perry R. Cook and Gary P. Scavone, 1995--2017.
- Contributions by Esteban Maestre, 2011.
- */
- /***************************************************/
-
- #include "Bowed.h"
- #include "SKINImsg.h"
-
- namespace stk {
-
- Bowed :: Bowed( StkFloat lowestFrequency )
- {
- if ( lowestFrequency <= 0.0 ) {
- oStream_ << "Bowed::Bowed: argument is less than or equal to zero!";
- handleError( StkError::FUNCTION_ARGUMENT );
- }
-
- unsigned long nDelays = (unsigned long) ( Stk::sampleRate() / lowestFrequency );
-
- neckDelay_.setMaximumDelay( nDelays + 1 );
- neckDelay_.setDelay( 100.0 );
-
- bridgeDelay_.setMaximumDelay( nDelays + 1 );
- bridgeDelay_.setDelay( 29.0 );
-
- bowTable_.setSlope( 3.0 );
- bowTable_.setOffset( 0.001);
- bowDown_ = false;
- maxVelocity_ = 0.25;
-
- vibrato_.setFrequency( 6.12723 );
- vibratoGain_ = 0.0;
-
- stringFilter_.setPole( 0.75 - (0.2 * 22050.0 / Stk::sampleRate()) );
- stringFilter_.setGain( 0.95 );
-
- // Old single body filter
- //bodyFilter_.setResonance( 500.0, 0.85, true );
- //bodyFilter_.setGain( 0.2 );
-
- // New body filter provided by Esteban Maestre (cascade of second-order sections)
- bodyFilters_[0].setCoefficients( 1.0, 1.5667, 0.3133, -0.5509, -0.3925 );
- bodyFilters_[1].setCoefficients( 1.0, -1.9537, 0.9542, -1.6357, 0.8697 );
- bodyFilters_[2].setCoefficients( 1.0, -1.6683, 0.8852, -1.7674, 0.8735 );
- bodyFilters_[3].setCoefficients( 1.0, -1.8585, 0.9653, -1.8498, 0.9516 );
- bodyFilters_[4].setCoefficients( 1.0, -1.9299, 0.9621, -1.9354, 0.9590 );
- bodyFilters_[5].setCoefficients( 1.0, -1.9800, 0.9888, -1.9867, 0.9923 );
-
- adsr_.setAllTimes( 0.02, 0.005, 0.9, 0.01 );
-
- betaRatio_ = 0.127236;
-
- // Necessary to initialize internal variables.
- this->setFrequency( 220.0 );
- this->clear();
- }
-
- Bowed :: ~Bowed( void )
- {
- }
-
- void Bowed :: clear( void )
- {
- neckDelay_.clear();
- bridgeDelay_.clear();
- stringFilter_.clear();
- for ( int i=0; i<6; i++ ) bodyFilters_[i].clear();
- }
-
- void Bowed :: setFrequency( StkFloat frequency )
- {
- #if defined(_STK_DEBUG_)
- if ( frequency <= 0.0 ) {
- oStream_ << "Bowed::setFrequency: argument is less than or equal to zero!";
- handleError( StkError::WARNING ); return;
- }
- #endif
-
- // Delay = length - approximate filter delay.
- baseDelay_ = Stk::sampleRate() / frequency - 4.0;
- if ( baseDelay_ <= 0.0 ) baseDelay_ = 0.3;
- bridgeDelay_.setDelay( baseDelay_ * betaRatio_ ); // bow to bridge length
- neckDelay_.setDelay( baseDelay_ * (1.0 - betaRatio_) ); // bow to nut (finger) length
- }
-
- void Bowed :: startBowing( StkFloat amplitude, StkFloat rate )
- {
- if ( amplitude <= 0.0 || rate <= 0.0 ) {
- oStream_ << "Bowed::startBowing: one or more arguments is less than or equal to zero!";
- handleError( StkError::WARNING ); return;
- }
-
- adsr_.setAttackRate( rate );
- adsr_.keyOn();
- maxVelocity_ = 0.03 + ( 0.2 * amplitude );
- bowDown_ = true;
- }
-
- void Bowed :: stopBowing( StkFloat rate )
- {
- if ( rate <= 0.0 ) {
- oStream_ << "Bowed::stopBowing: argument is less than or equal to zero!";
- handleError( StkError::WARNING ); return;
- }
-
- adsr_.setReleaseRate( rate );
- adsr_.keyOff();
- }
-
- void Bowed :: noteOn( StkFloat frequency, StkFloat amplitude )
- {
- this->startBowing( amplitude, amplitude * 0.001 );
- this->setFrequency( frequency );
- }
-
- void Bowed :: noteOff( StkFloat amplitude )
- {
- this->stopBowing( (1.0 - amplitude) * 0.005 );
- }
-
- void Bowed :: controlChange( int number, StkFloat value )
- {
- #if defined(_STK_DEBUG_)
- if ( value < 0 || ( number != 101 && value > 128.0 ) ) {
- oStream_ << "Bowed::controlChange: value (" << value << ") is out of range!";
- handleError( StkError::WARNING ); return;
- }
- #endif
-
- StkFloat normalizedValue = value * ONE_OVER_128;
- if ( number == __SK_BowPressure_ ) { // 2
- if ( normalizedValue > 0.0 ) bowDown_ = true;
- else bowDown_ = false;
- bowTable_.setSlope( 5.0 - (4.0 * normalizedValue) );
- }
- else if ( number == __SK_BowPosition_ ) { // 4
- betaRatio_ = normalizedValue;
- bridgeDelay_.setDelay( baseDelay_ * betaRatio_ );
- neckDelay_.setDelay( baseDelay_ * (1.0 - betaRatio_) );
- }
- else if ( number == __SK_ModFrequency_ ) // 11
- vibrato_.setFrequency( normalizedValue * 12.0 );
- else if ( number == __SK_ModWheel_ ) // 1
- vibratoGain_ = ( normalizedValue * 0.4 );
- else if ( number == 100 ) // 100: set instantaneous bow velocity
- adsr_.setTarget( normalizedValue );
- else if ( number == 101 ) // 101: set instantaneous value of frequency
- this->setFrequency( value );
- else if (number == __SK_AfterTouch_Cont_) // 128
- adsr_.setTarget( normalizedValue );
- #if defined(_STK_DEBUG_)
- else {
- oStream_ << "Bowed::controlChange: undefined control number (" << number << ")!";
- handleError( StkError::WARNING );
- }
- #endif
- }
-
- } // stk namespace
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