stk::Resonate Class Reference

STK noise driven formant filter. More...

#include <Resonate.h>

Inheritance diagram for stk::Resonate:

Public Member Functions
	Resonate (void)
	Class constructor.
	~Resonate (void)
	Class destructor.
void	setResonance (StkFloat frequency, StkFloat radius)
	Set the filter for a resonance at the given frequency (Hz) and radius.
void	setNotch (StkFloat frequency, StkFloat radius)
	Set the filter for a notch at the given frequency (Hz) and radius.
void	setEqualGainZeroes (void)
	Set the filter zero coefficients for contant resonance gain.
void	keyOn (void)
	Initiate the envelope with a key-on event.
void	keyOff (void)
	Signal a key-off event to the envelope.
void	noteOn (StkFloat frequency, StkFloat amplitude)
	Start a note with the given frequency and amplitude.
void	noteOff (StkFloat amplitude)
	Stop a note with the given amplitude (speed of decay).
void	controlChange (int number, StkFloat value)
	Perform the control change specified by number and value (0.0 - 128.0).
StkFloat	tick (unsigned int channel=0)
	Compute and return one output sample.
StkFrames &	tick (StkFrames &frames, unsigned int channel=0)
	Fill a channel of the StkFrames object with computed outputs.
Public Member Functions inherited from stk::Instrmnt
	Instrmnt (void)
	Class constructor.
virtual void	clear (void)
	Reset and clear all internal state (for subclasses).
virtual void	noteOn (StkFloat frequency, StkFloat amplitude)=0
	Start a note with the given frequency and amplitude.
virtual void	noteOff (StkFloat amplitude)=0
	Stop a note with the given amplitude (speed of decay).
virtual void	setFrequency (StkFloat frequency)
	Set instrument parameters for a particular frequency.
virtual void	controlChange (int number, StkFloat value)
	Perform the control change specified by number and value (0.0 - 128.0).
unsigned int	channelsOut (void) const
	Return the number of output channels for the class.
const StkFrames &	lastFrame (void) const
	Return an StkFrames reference to the last output sample frame.
StkFloat	lastOut (unsigned int channel=0)
	Return the specified channel value of the last computed frame.
virtual StkFloat	tick (unsigned int channel=0)=0
	Compute one sample frame and return the specified channel value.
virtual StkFrames &	tick (StkFrames &frames, unsigned int channel=0)=0
	Fill the StkFrames object with computed sample frames, starting at the specified channel.
Public Member Functions inherited from stk::Stk
void	ignoreSampleRateChange (bool ignore=true)
	A function to enable/disable the automatic updating of class data when the STK sample rate changes.

Additional Inherited Members
Static Public Member Functions inherited from stk::Stk
static StkFloat	sampleRate (void)
	Static method that returns the current STK sample rate.
static void	setSampleRate (StkFloat rate)
	Static method that sets the STK sample rate.
static void	clear_alertList ()
	Static method that frees memory from alertList_.
static std::string	rawwavePath (void)
	Static method that returns the current rawwave path.
static void	setRawwavePath (std::string path)
	Static method that sets the STK rawwave path.
static void	swap16 (unsigned char *ptr)
	Static method that byte-swaps a 16-bit data type.
static void	swap32 (unsigned char *ptr)
	Static method that byte-swaps a 32-bit data type.
static void	swap64 (unsigned char *ptr)
	Static method that byte-swaps a 64-bit data type.
static void	sleep (unsigned long milliseconds)
	Static cross-platform method to sleep for a number of milliseconds.
static bool	inRange (StkFloat value, StkFloat min, StkFloat max)
	Static method to check whether a value is within a specified range.
static void	handleError (const char *message, StkError::Type type)
	Static function for error reporting and handling using c-strings.
static void	handleError (std::string message, StkError::Type type)
	Static function for error reporting and handling using c++ strings.
static void	showWarnings (bool status)
	Toggle display of WARNING and STATUS messages.
static void	printErrors (bool status)
	Toggle display of error messages before throwing exceptions.
Static Public Attributes inherited from stk::Stk
static const StkFormat	STK_SINT8
static const StkFormat	STK_SINT16
static const StkFormat	STK_SINT24
static const StkFormat	STK_SINT32
static const StkFormat	STK_FLOAT32
static const StkFormat	STK_FLOAT64
Protected Member Functions inherited from stk::Stk
	Stk (void)
	Default constructor.
virtual	~Stk (void)
	Class destructor.
virtual void	sampleRateChanged (StkFloat newRate, StkFloat oldRate)
	This function should be implemented in subclasses that depend on the sample rate.
void	addSampleRateAlert (Stk *ptr)
	Add class pointer to list for sample rate change notification.
void	removeSampleRateAlert (Stk *ptr)
	Remove class pointer from list for sample rate change notification.
void	handleError (StkError::Type type) const
	Internal function for error reporting that assumes message in oStream_ variable.

Detailed Description

STK noise driven formant filter.

This instrument contains a noise source, which excites a biquad resonance filter, with volume controlled by an ADSR.

Control Change Numbers:

• Resonance Frequency (0-Nyquist) = 2
• Pole Radii = 4
• Notch Frequency (0-Nyquist) = 11
• Zero Radii = 1
• Envelope Gain = 128

by Perry R. Cook and Gary P. Scavone, 1995–2023.

Member Function Documentation

tick()

StkFrames & stk::Resonate::tick ( StkFrames &  frames, unsigned int  channel = 0  )

inlinevirtual

Fill a channel of the StkFrames object with computed outputs.

The 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.

Implements stk::Instrmnt.

{
  unsigned int nChannels = lastFrame_.channels();
#if defined(_STK_DEBUG_)
  if ( channel > frames.channels() - nChannels ) {
    oStream_ << "Resonate::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;
}

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The documentation for this class was generated from the following file:

• Resonate.h