SF2::Render::LFO Class Reference

Implementation of a low-frequency triangular oscillator. More...

#include <LFO.hpp>

Classes
struct	Config
	Configures an LFO via a "fluent" interface. More...
struct	State

Public Member Functions
	LFO (Float sampleRate, Float frequency, Float delay)
	Create a new instance. More...
void	initialize (Float sampleRate, Float frequency, Float delay)
	Initialize the LFO with the given parameters. More...
void	setFrequency (Float frequency)
	Set the frequency of the oscillator. More...
void	setDelay (Float delay)
	Set the delay of the oscillator in seconds. More...
void	reset ()
	Restart from a known zero state. More...
State	saveState () const
	Save the state of the oscillator. More...
void	restoreState (const State &state)
	Restore the oscillator to a previously-saved state. More...
void	increment ()
	Increment the oscillator to the next value. More...
Float	valueAndIncrement ()
	Obtain the next value of the oscillator. More...
Float	value ()
	Obtain the current value of the oscillator. More...

Detailed Description

Implementation of a low-frequency triangular oscillator.

By design, this LFO emits bipolar values from -1.0 to 1.0 in order to be useful in SF2 processing. One can obtain unipolar values via the DSP::bipolarToUnipolar method. An LFO will start emitting with value 0.0, again by design, in order to smoothly transition from a paused LFO into a running one.

Constructor & Destructor Documentation

LFO()

SF2::Render::LFO::LFO ( Float  sampleRate, Float  frequency, Float  delay  )

inline

Create a new instance.

Parameters

sampleRate	number of samples per second
frequency	the frequency of the oscillator
delay	the number of seconds to wait before starting the LFO.

References initialize().

Referenced by SF2::Render::LFO::Config::make().

Member Function Documentation

increment()

void SF2::Render::LFO::increment ( )

inline

Increment the oscillator to the next value.

Referenced by valueAndIncrement().

initialize()

void SF2::Render::LFO::initialize ( Float  sampleRate, Float  frequency, Float  delay  )

inline

Initialize the LFO with the given parameters.

Parameters

sampleRate	number of samples per second
frequency	the frequency of the oscillator
delay	the number of seconds to wait before starting the LFO.

References reset().

Referenced by LFO().

reset()

void SF2::Render::LFO::reset ( )

inline

Restart from a known zero state.

Referenced by initialize(), and setDelay().

restoreState()

void SF2::Render::LFO::restoreState ( const State &  state )

inline

Restore the oscillator to a previously-saved state.

Parameters

state

the state to restore to

References SF2::Render::LFO::State::counter_, and SF2::Render::LFO::State::delaySampleCount_.

saveState()

State SF2::Render::LFO::saveState ( ) const

inline

Save the state of the oscillator.

Returns

current internal state

setDelay()

void SF2::Render::LFO::setDelay ( Float  delay )

inline

Set the delay of the oscillator in seconds.

NOTE: resets the counter.

Parameters

delay

the number of seconds to wait before starting the LFO.

References reset().

setFrequency()

void SF2::Render::LFO::setFrequency ( Float  frequency )

inline

Set the frequency of the oscillator.

NOTE: it does not reset the counter.

Parameters

frequency

the frequency to operate at

value()

Float SF2::Render::LFO::value ( )

inline

Obtain the current value of the oscillator.

Returns

current waveform value

valueAndIncrement()

Float SF2::Render::LFO::valueAndIncrement ( )

inline

Obtain the next value of the oscillator.

Advances counter before returning, so this is not idempotent.

Returns

current waveform value

References increment().

Referenced by SF2::Render::Voice::Voice::render().

---

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

• SoundFontInfoLib/SoundFontInfoLib/Render/LFO.hpp