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- #ifndef STK_BEETHREE_H
- #define STK_BEETHREE_H
-
- #include "FM.h"
-
- namespace stk {
-
- /***************************************************/
- /*! \class BeeThree
- \brief STK Hammond-oid organ FM synthesis instrument.
-
- This class implements a simple 4 operator
- topology, also referred to as algorithm 8 of
- the TX81Z.
-
- \code
- Algorithm 8 is :
- 1 --.
- 2 -\|
- +-> Out
- 3 -/|
- 4 --
- \endcode
-
- Control Change Numbers:
- - Operator 4 (feedback) Gain = 2
- - Operator 3 Gain = 4
- - LFO Speed = 11
- - LFO Depth = 1
- - ADSR 2 & 4 Target = 128
-
- The basic Chowning/Stanford FM patent expired
- in 1995, but there exist follow-on patents,
- mostly assigned to Yamaha. If you are of the
- type who should worry about this (making
- money) worry away.
-
- by Perry R. Cook and Gary P. Scavone, 1995--2017.
- */
- /***************************************************/
-
- class BeeThree : public FM
- {
- public:
- //! Class constructor.
- /*!
- An StkError will be thrown if the rawwave path is incorrectly set.
- */
- BeeThree( void );
-
- //! Class destructor.
- ~BeeThree( void );
-
- //! Start a note with the given frequency and amplitude.
- void noteOn( StkFloat frequency, StkFloat amplitude );
-
- //! 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:
-
- };
-
- inline StkFloat BeeThree :: tick( unsigned int )
- {
- StkFloat temp;
-
- if ( modDepth_ > 0.0 ) {
- temp = 1.0 + ( modDepth_ * vibrato_.tick() * 0.1 );
- waves_[0]->setFrequency( baseFrequency_ * temp * ratios_[0] );
- waves_[1]->setFrequency( baseFrequency_ * temp * ratios_[1] );
- waves_[2]->setFrequency( baseFrequency_ * temp * ratios_[2] );
- waves_[3]->setFrequency( baseFrequency_ * temp * ratios_[3] );
- }
-
- waves_[3]->addPhaseOffset( twozero_.lastOut() );
- temp = control1_ * 2.0 * gains_[3] * adsr_[3]->tick() * waves_[3]->tick();
- twozero_.tick( temp );
-
- temp += control2_ * 2.0 * gains_[2] * adsr_[2]->tick() * waves_[2]->tick();
- temp += gains_[1] * adsr_[1]->tick() * waves_[1]->tick();
- temp += gains_[0] * adsr_[0]->tick() * waves_[0]->tick();
-
- lastFrame_[0] = temp * 0.125;
- return lastFrame_[0];
- }
-
- inline StkFrames& BeeThree :: tick( StkFrames& frames, unsigned int channel )
- {
- unsigned int nChannels = lastFrame_.channels();
- #if defined(_STK_DEBUG_)
- if ( channel > frames.channels() - nChannels ) {
- oStream_ << "BeeThree::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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