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

90 lines
2.3 KiB
C++

#ifndef STK_HEVYMETL_H
#define STK_HEVYMETL_H
#include "FM.h"
namespace stk {
/***************************************************/
/*! \class HevyMetl
\brief STK heavy metal FM synthesis instrument.
This class implements 3 cascade operators with
feedback modulation, also referred to as
algorithm 3 of the TX81Z.
\code
Algorithm 3 is : 4--\
3-->2-- + -->1-->Out
\endcode
Control Change Numbers:
- Total Modulator Index = 2
- Modulator Crossfade = 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 HevyMetl : public FM
{
public:
//! Class constructor.
/*!
An StkError will be thrown if the rawwave path is incorrectly set.
*/
HevyMetl( void );
//! Class destructor.
~HevyMetl( 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 );
protected:
};
inline StkFloat HevyMetl :: tick( unsigned int )
{
register StkFloat temp;
temp = vibrato_.tick() * modDepth_ * 0.2;
waves_[0]->setFrequency(baseFrequency_ * (1.0 + temp) * ratios_[0]);
waves_[1]->setFrequency(baseFrequency_ * (1.0 + temp) * ratios_[1]);
waves_[2]->setFrequency(baseFrequency_ * (1.0 + temp) * ratios_[2]);
waves_[3]->setFrequency(baseFrequency_ * (1.0 + temp) * ratios_[3]);
temp = gains_[2] * adsr_[2]->tick() * waves_[2]->tick();
waves_[1]->addPhaseOffset( temp );
waves_[3]->addPhaseOffset( twozero_.lastOut() );
temp = (1.0 - (control2_ * 0.5)) * gains_[3] * adsr_[3]->tick() * waves_[3]->tick();
twozero_.tick(temp);
temp += control2_ * 0.5 * gains_[1] * adsr_[1]->tick() * waves_[1]->tick();
temp = temp * control1_;
waves_[0]->addPhaseOffset( temp );
temp = gains_[0] * adsr_[0]->tick() * waves_[0]->tick();
lastFrame_[0] = temp * 0.5;
return lastFrame_[0];
}
} // stk namespace
#endif