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stk/include/FMVoices.h
Gary Scavone eccd8c9981 Version 4.4.0
2013-09-29 23:11:39 +02:00

99 lines
2.6 KiB
C++

#ifndef STK_FMVOICES_H
#define STK_FMVOICES_H
#include "FM.h"
namespace stk {
/***************************************************/
/*! \class FMVoices
\brief STK singing FM synthesis instrument.
This class implements 3 carriers and a common
modulator, also referred to as algorithm 6 of
the TX81Z.
\code
Algorithm 6 is :
/->1 -\
4-|-->2 - +-> Out
\->3 -/
\endcode
Control Change Numbers:
- Vowel = 2
- Spectral Tilt = 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 - 2009.
*/
/***************************************************/
class FMVoices : public FM
{
public:
//! Class constructor.
/*!
An StkError will be thrown if the rawwave path is incorrectly set.
*/
FMVoices( void );
//! Class destructor.
~FMVoices( void );
//! Set instrument parameters for a particular frequency.
void setFrequency( StkFloat frequency );
//! Start a note with the given frequency and amplitude.
void noteOn( StkFloat frequency, 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 );
protected:
int currentVowel_;
StkFloat tilt_[3];
StkFloat mods_[3];
};
inline StkFloat FMVoices :: tick( unsigned int )
{
register StkFloat temp, temp2;
temp = gains_[3] * adsr_[3]->tick() * waves_[3]->tick();
temp2 = vibrato_.tick() * modDepth_ * 0.1;
waves_[0]->setFrequency(baseFrequency_ * (1.0 + temp2) * ratios_[0]);
waves_[1]->setFrequency(baseFrequency_ * (1.0 + temp2) * ratios_[1]);
waves_[2]->setFrequency(baseFrequency_ * (1.0 + temp2) * ratios_[2]);
waves_[3]->setFrequency(baseFrequency_ * (1.0 + temp2) * ratios_[3]);
waves_[0]->addPhaseOffset(temp * mods_[0]);
waves_[1]->addPhaseOffset(temp * mods_[1]);
waves_[2]->addPhaseOffset(temp * mods_[2]);
waves_[3]->addPhaseOffset( twozero_.lastOut() );
twozero_.tick( temp );
temp = gains_[0] * tilt_[0] * adsr_[0]->tick() * waves_[0]->tick();
temp += gains_[1] * tilt_[1] * adsr_[1]->tick() * waves_[1]->tick();
temp += gains_[2] * tilt_[2] * adsr_[2]->tick() * waves_[2]->tick();
lastFrame_[0] = temp * 0.33;
return lastFrame_[0];
}
} // stk namespace
#endif