Brass.h

#ifndef STK_BRASS_H
#define STK_BRASS_H
 
#include "Instrmnt.h"
#include "DelayA.h"
#include "BiQuad.h"
#include "PoleZero.h"
#include "ADSR.h"
#include "SineWave.h"
 
namespace stk {
 
/***************************************************/
/***************************************************/
 
class Brass: public Instrmnt
{
 public:
 
  Brass( StkFloat lowestFrequency = 8.0 );
 
  ~Brass(  );
 
  void clear(  );
 
  void setFrequency( StkFloat frequency );
 
  void setLip( StkFloat frequency );
 
  void startBlowing( StkFloat amplitude, StkFloat rate );
 
  void stopBlowing( StkFloat rate );
 
  void noteOn( StkFloat frequency, StkFloat amplitude );
 
  void noteOff( StkFloat amplitude );
 
  void controlChange( int number, StkFloat value );
 
  StkFloat tick( unsigned int channel = 0 );
 
 
  StkFrames& tick( StkFrames& frames, unsigned int channel = 0 );
 
 protected:
 
  DelayA   delayLine_;
  BiQuad   lipFilter_;
  PoleZero dcBlock_;
  ADSR     adsr_;
  SineWave vibrato_;
 
  StkFloat lipTarget_;
  StkFloat slideTarget_;
  StkFloat vibratoGain_;
  StkFloat maxPressure_;
 
};
 
inline StkFloat Brass :: tick( unsigned int )
{
  StkFloat breathPressure = maxPressure_ * adsr_.tick();
  breathPressure += vibratoGain_ * vibrato_.tick();
 
  StkFloat mouthPressure = 0.3 * breathPressure;
  StkFloat borePressure = 0.85 * delayLine_.lastOut();
  StkFloat deltaPressure = mouthPressure - borePressure; // Differential pressure.
  deltaPressure = lipFilter_.tick( deltaPressure );      // Force - > position.
  deltaPressure *= deltaPressure;                        // Basic position to area mapping.
  if ( deltaPressure > 1.0 ) deltaPressure = 1.0;        // Non-linear saturation.
 
  // The following input scattering assumes the mouthPressure = area.
  lastFrame_[0] = deltaPressure * mouthPressure + ( 1.0 - deltaPressure) * borePressure;
  lastFrame_[0] = delayLine_.tick( dcBlock_.tick( lastFrame_[0] ) );
 
  return lastFrame_[0];
}
 
inline StkFrames& Brass :: tick( StkFrames& frames, unsigned int channel )
{
  unsigned int nChannels = lastFrame_.channels();
#if defined(_STK_DEBUG_)
  if ( channel > frames.channels() - nChannels ) {
    oStream_ << "Brass::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