mirror of
https://github.com/overte-org/overte.git
synced 2025-06-23 00:20:01 +02:00
129 lines
3.4 KiB
C++
129 lines
3.4 KiB
C++
#ifndef STK_SITAR_H
|
|
#define STK_SITAR_H
|
|
|
|
#include "Instrmnt.h"
|
|
#include "DelayA.h"
|
|
#include "OneZero.h"
|
|
#include "Noise.h"
|
|
#include "ADSR.h"
|
|
#include <cmath>
|
|
|
|
namespace stk {
|
|
|
|
/***************************************************/
|
|
/*! \class Sitar
|
|
\brief STK sitar string model class.
|
|
|
|
This class implements a sitar plucked string
|
|
physical model based on the Karplus-Strong
|
|
algorithm.
|
|
|
|
This is a digital waveguide model, making its
|
|
use possibly subject to patents held by
|
|
Stanford University, Yamaha, and others.
|
|
There exist at least two patents, assigned to
|
|
Stanford, bearing the names of Karplus and/or
|
|
Strong.
|
|
|
|
by Perry R. Cook and Gary P. Scavone, 1995-2012.
|
|
*/
|
|
/***************************************************/
|
|
|
|
class Sitar : public Instrmnt
|
|
{
|
|
public:
|
|
//! Class constructor, taking the lowest desired playing frequency.
|
|
Sitar( StkFloat lowestFrequency = 8.0 );
|
|
|
|
//! Class destructor.
|
|
~Sitar( void );
|
|
|
|
//! Reset and clear all internal state.
|
|
void clear( void );
|
|
|
|
//! Set instrument parameters for a particular frequency.
|
|
void setFrequency( StkFloat frequency );
|
|
|
|
//! Pluck the string with the given amplitude using the current frequency.
|
|
void pluck( StkFloat amplitude );
|
|
|
|
//! 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 );
|
|
|
|
//! 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:
|
|
|
|
DelayA delayLine_;
|
|
OneZero loopFilter_;
|
|
Noise noise_;
|
|
ADSR envelope_;
|
|
|
|
StkFloat loopGain_;
|
|
StkFloat amGain_;
|
|
StkFloat delay_;
|
|
StkFloat targetDelay_;
|
|
|
|
};
|
|
|
|
inline StkFloat Sitar :: tick( unsigned int )
|
|
{
|
|
if ( fabs(targetDelay_ - delay_) > 0.001 ) {
|
|
if ( targetDelay_ < delay_ )
|
|
delay_ *= 0.99999;
|
|
else
|
|
delay_ *= 1.00001;
|
|
delayLine_.setDelay( delay_ );
|
|
}
|
|
|
|
lastFrame_[0] = delayLine_.tick( loopFilter_.tick( delayLine_.lastOut() * loopGain_ ) +
|
|
(amGain_ * envelope_.tick() * noise_.tick()));
|
|
|
|
return lastFrame_[0];
|
|
}
|
|
|
|
inline StkFrames& Sitar :: tick( StkFrames& frames, unsigned int channel )
|
|
{
|
|
unsigned int nChannels = lastFrame_.channels();
|
|
#if defined(_STK_DEBUG_)
|
|
if ( channel > frames.channels() - nChannels ) {
|
|
oStream_ << "Sitar::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
|
|
|