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- #ifndef STK_SAXOFONY_H
- #define STK_SAXOFONY_H
-
- #include "Instrmnt.h"
- #include "DelayL.h"
- #include "ReedTable.h"
- #include "OneZero.h"
- #include "Envelope.h"
- #include "Noise.h"
- #include "SineWave.h"
-
- namespace stk {
-
- /***************************************************/
- /*! \class Saxofony
- \brief STK faux conical bore reed instrument class.
-
- This class implements a "hybrid" digital
- waveguide instrument that can generate a
- variety of wind-like sounds. It has also been
- referred to as the "blowed string" model. The
- waveguide section is essentially that of a
- string, with one rigid and one lossy
- termination. The non-linear function is a
- reed table. The string can be "blown" at any
- point between the terminations, though just as
- with strings, it is impossible to excite the
- system at either end. If the excitation is
- placed at the string mid-point, the sound is
- that of a clarinet. At points closer to the
- "bridge", the sound is closer to that of a
- saxophone. See Scavone (2002) for more details.
-
- This is a digital waveguide model, making its
- use possibly subject to patents held by Stanford
- University, Yamaha, and others.
-
- Control Change Numbers:
- - Reed Stiffness = 2
- - Reed Aperture = 26
- - Noise Gain = 4
- - Blow Position = 11
- - Vibrato Frequency = 29
- - Vibrato Gain = 1
- - Breath Pressure = 128
-
- by Perry R. Cook and Gary P. Scavone, 1995--2017.
- */
- /***************************************************/
-
- class Saxofony : public Instrmnt
- {
- public:
- //! Class constructor, taking the lowest desired playing frequency.
- /*!
- An StkError will be thrown if the rawwave path is incorrectly set.
- */
- Saxofony( StkFloat lowestFrequency );
-
- //! Class destructor.
- ~Saxofony( void );
-
- //! Reset and clear all internal state.
- void clear( void );
-
- //! Set instrument parameters for a particular frequency.
- void setFrequency( StkFloat frequency );
-
- //! Set the "blowing" position between the air column terminations (0.0 - 1.0).
- void setBlowPosition( StkFloat aPosition );
-
- //! Apply breath pressure to instrument with given amplitude and rate of increase.
- void startBlowing( StkFloat amplitude, StkFloat rate );
-
- //! Decrease breath pressure with given rate of decrease.
- void stopBlowing( StkFloat rate );
-
- //! Start a note with the given frequency and amplitude.
- void noteOn( StkFloat frequency, StkFloat amplitude );
-
- //! Stop a note with the given amplitude (speed of decay).
- void noteOff( StkFloat amplitude );
-
- //! Perform the control change specified by \e number and \e value (0.0 - 128.0).
- void controlChange( int number, StkFloat value );
-
- //! Compute and return one output sample.
- StkFloat tick( unsigned int channel = 0 );
-
- //! Fill a channel of the StkFrames object with computed outputs.
- /*!
- The \c channel argument must be less than the number of
- channels in the StkFrames argument (the first channel is specified
- by 0). However, range checking is only performed if _STK_DEBUG_
- is defined during compilation, in which case an out-of-range value
- will trigger an StkError exception.
- */
- StkFrames& tick( StkFrames& frames, unsigned int channel = 0 );
-
- protected:
-
- DelayL delays_[2];
- ReedTable reedTable_;
- OneZero filter_;
- Envelope envelope_;
- Noise noise_;
- SineWave vibrato_;
-
- StkFloat outputGain_;
- StkFloat noiseGain_;
- StkFloat vibratoGain_;
- StkFloat position_;
-
- };
-
- inline StkFloat Saxofony :: tick( unsigned int )
- {
- StkFloat pressureDiff;
- StkFloat breathPressure;
- StkFloat temp;
-
- // Calculate the breath pressure (envelope + noise + vibrato)
- breathPressure = envelope_.tick();
- breathPressure += breathPressure * noiseGain_ * noise_.tick();
- breathPressure += breathPressure * vibratoGain_ * vibrato_.tick();
-
- temp = -0.95 * filter_.tick( delays_[0].lastOut() );
- lastFrame_[0] = temp - delays_[1].lastOut();
- pressureDiff = breathPressure - lastFrame_[0];
- delays_[1].tick( temp );
- delays_[0].tick( breathPressure - (pressureDiff * reedTable_.tick(pressureDiff)) - temp );
-
- lastFrame_[0] *= outputGain_;
- return lastFrame_[0];
- }
-
- inline StkFrames& Saxofony :: tick( StkFrames& frames, unsigned int channel )
- {
- unsigned int nChannels = lastFrame_.channels();
- #if defined(_STK_DEBUG_)
- if ( channel > frames.channels() - nChannels ) {
- oStream_ << "Saxofony::tick(): channel and StkFrames arguments are incompatible!";
- handleError( StkError::FUNCTION_ARGUMENT );
- }
- #endif
-
- StkFloat *samples = &frames[channel];
- unsigned int j, hop = frames.channels() - nChannels;
- if ( nChannels == 1 ) {
- for ( unsigned int i=0; i<frames.frames(); i++, samples += hop )
- *samples++ = tick();
- }
- else {
- for ( unsigned int i=0; i<frames.frames(); i++, samples += hop ) {
- *samples++ = tick();
- for ( j=1; j<nChannels; j++ )
- *samples++ = lastFrame_[j];
- }
- }
-
- return frames;
- }
-
- } // stk namespace
-
- #endif
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