A simple ADSR envelope generator. More...

#include <ADSR.h>

Public Member Functions
	ADSR ()
	Constructor.

void	update ()
	Updates the internal controls of the ADSR. More...

unsigned char	next ()
	Advances one audio step along the ADSR and returns the level. More...

void	noteOn (bool reset=false)
	Start the attack phase of the ADSR. More...

void	noteOff ()
	Start the release phase of the ADSR. More...

void	setAttackLevel (byte value)
	Set the attack level of the ADSR. More...

void	setDecayLevel (byte value)
	Set the decay level of the ADSR. More...

void	setSustainLevel (byte value)
	Set the sustain level of the ADSR. More...

void	setReleaseLevel (byte value)
	Set the release level of the ADSR. More...

void	setIdleLevel (byte value)

void	setADLevels (byte attack, byte decay)
	Set the attack and decay levels of the ADSR. More...

void	setLevels (byte attack, byte decay, byte sustain, byte release)
	Set the attack, decay, sustain and release levels. More...

void	setAttackTime (unsigned int msec)
	Set the attack time of the ADSR in milliseconds. More...

void	setDecayTime (unsigned int msec)
	Set the decay time of the ADSR in milliseconds. More...

void	setSustainTime (unsigned int msec)
	Set the sustain time of the ADSR in milliseconds. More...

void	setReleaseTime (unsigned int msec)
	Set the release time of the ADSR in milliseconds. More...

void	setIdleTime (unsigned int msec)

void	setTimes (unsigned int attack_ms, unsigned int decay_ms, unsigned int sustain_ms, unsigned int release_ms)
	Set the attack, decay and release times of the ADSR in milliseconds. More...

void	setAttackUpdateSteps (unsigned int steps)
	Set the attack time of the ADSR, expressed as the number of update steps (not ADSR::next() interpolation steps) in the attack phase. More...

void	setDecayUpdateSteps (unsigned int steps)
	Set the decay time of the ADSR, expressed as the number of update steps (not ADSR::next() interpolation steps) in the decay phase. More...

void	setSustainUpdateSteps (unsigned int steps)
	Set the sustain time of the ADSR, expressed as the number of update steps (not ADSR::next() interpolation steps) in the sustain phase. More...

void	setReleaseUpdateSteps (unsigned int steps)
	Set the release time of the ADSR, expressed as the number of update steps (not ADSR::next() interpolation steps) in the release phase. More...

void	setIdleUpdateSteps (unsigned int steps)

void	setAllUpdateSteps (unsigned int attack_steps, unsigned int decay_steps, unsigned int sustain_steps, unsigned int release_steps)
	Set the attack, decay and release times of the ADSR, expressed in update steps (not ADSR::next() interpolation steps). More...

bool	playing ()
	Tells if the envelope is currently playing. More...

Public Attributes
bool	adsr_playing

Detailed Description

template<unsigned int CONTROL_UPDATE_RATE, unsigned int LERP_RATE, typename T = unsigned int>
class ADSR< CONTROL_UPDATE_RATE, LERP_RATE, T >

A simple ADSR envelope generator.

This implementation has separate update() and next() methods, where next() interpolates values between each update(). The "normal" way to use this would be with update() in updateControl(), where it calculates a new internal state each control step, and then next() is in updateAudio(), called much more often, where it interpolates between the control values. This also allows the ADSR updates to be made even more sparsely if desired, eg. every 3rd control update.

Template Parameters

CONTROL_UPDATE_RATE The frequency of control updates. Ordinarily this will be CONTROL_RATE, but an alternative (amongst others) is to set this as well as the LERP_RATE parameter to AUDIO_RATE, and call both update() and next() in updateAudio(). Such a use would allow accurate envelopes with finer resolution of the control points than CONTROL_RATE.

LERP_RATE Sets how often next() will be called, to interpolate between updates set by CONTROL_UPDATE_RATE. This will produce the smoothest results if it's set to AUDIO_RATE, but if you need to save processor time and your envelope changes slowly or controls something like a filter where there may not be problems with glitchy or clicking transitions, LERP_RATE could be set to CONTROL_RATE (for instance). Then update() and next() could both be called in updateControl(), greatly reducing the amount of processing required compared to calling next() in updateAudio().

Definition at line 45 of file ADSR.h.

Member Function Documentation

◆ next()

template<unsigned int CONTROL_UPDATE_RATE, unsigned int LERP_RATE, typename T = unsigned int>

unsigned char ADSR< CONTROL_UPDATE_RATE, LERP_RATE, T >::next ( )

inline

Advances one audio step along the ADSR and returns the level.

Call this in updateAudio().

Returns: the next value, as an unsigned char.

Definition at line 165 of file ADSR.h.

◆ noteOff()

template<unsigned int CONTROL_UPDATE_RATE, unsigned int LERP_RATE, typename T = unsigned int>

void ADSR< CONTROL_UPDATE_RATE, LERP_RATE, T >::noteOff ( )

inline

Start the release phase of the ADSR.

Definition at line 192 of file ADSR.h.

◆ noteOn()

template<unsigned int CONTROL_UPDATE_RATE, unsigned int LERP_RATE, typename T = unsigned int>

void ADSR< CONTROL_UPDATE_RATE, LERP_RATE, T >::noteOn ( bool reset = false )

inline

Start the attack phase of the ADSR.

This will restart the ADSR no matter what phase it is up to.

Parameters

reset If true, the envelope will start from 0, even if it is still playing (often useful for effect envelopes). If false (default if omitted), the envelope will start rising from the current level, which could be non-zero, if it is still playing (most useful for note envelopes).

Definition at line 180 of file ADSR.h.

◆ playing()

template<unsigned int CONTROL_UPDATE_RATE, unsigned int LERP_RATE, typename T = unsigned int>

bool ADSR< CONTROL_UPDATE_RATE, LERP_RATE, T >::playing ( )

inline

Tells if the envelope is currently playing.

Returns: true if playing, false if in IDLE state

Definition at line 431 of file ADSR.h.

◆ setADLevels()

template<unsigned int CONTROL_UPDATE_RATE, unsigned int LERP_RATE, typename T = unsigned int>

void ADSR< CONTROL_UPDATE_RATE, LERP_RATE, T >::setADLevels	(	byte	attack,
		byte	decay
	)

inline

Set the attack and decay levels of the ADSR.

This assumes a conventional ADSR where the sustain continues at the same level as the decay, till the release ramps to 0.

Parameters

attack	the new attack level.
decay	the new decay level.

Definition at line 253 of file ADSR.h.

◆ setAllUpdateSteps()

template<unsigned int CONTROL_UPDATE_RATE, unsigned int LERP_RATE, typename T = unsigned int>

void ADSR< CONTROL_UPDATE_RATE, LERP_RATE, T >::setAllUpdateSteps	(	unsigned int	attack_steps,
		unsigned int	decay_steps,
		unsigned int	sustain_steps,
		unsigned int	release_steps
	)

inline

Set the attack, decay and release times of the ADSR, expressed in update steps (not ADSR::next() interpolation steps).

Parameters

attack_steps	the number of update steps in the attack phase
decay_steps	the number of update steps in the decay phase
sustain_steps	the number of update steps in the sustain phase
release_steps	the number of update steps in the release phase

Definition at line 415 of file ADSR.h.

◆ setAttackLevel()

template<unsigned int CONTROL_UPDATE_RATE, unsigned int LERP_RATE, typename T = unsigned int>

void ADSR< CONTROL_UPDATE_RATE, LERP_RATE, T >::setAttackLevel ( byte value )

inline

Set the attack level of the ADSR.

Parameters

value the attack level.

Definition at line 202 of file ADSR.h.

◆ setAttackTime()

template<unsigned int CONTROL_UPDATE_RATE, unsigned int LERP_RATE, typename T = unsigned int>

void ADSR< CONTROL_UPDATE_RATE, LERP_RATE, T >::setAttackTime ( unsigned int msec )

inline

Set the attack time of the ADSR in milliseconds.

The actual time taken will be resolved within the resolution of CONTROL_RATE.

Parameters

msec	the unsigned int attack time in milliseconds.

Note: Beware of low values (less than 20 or so, depending on how many steps are being taken), in case internal step size gets calculated as 0, which would mean nothing happens.

Definition at line 287 of file ADSR.h.

◆ setAttackUpdateSteps()

template<unsigned int CONTROL_UPDATE_RATE, unsigned int LERP_RATE, typename T = unsigned int>

void ADSR< CONTROL_UPDATE_RATE, LERP_RATE, T >::setAttackUpdateSteps ( unsigned int steps )

inline

Set the attack time of the ADSR, expressed as the number of update steps (not ADSR::next() interpolation steps) in the attack phase.

Parameters

steps the number of times ADSR::update() will be called in the attack phase.

Definition at line 366 of file ADSR.h.

◆ setDecayLevel()

template<unsigned int CONTROL_UPDATE_RATE, unsigned int LERP_RATE, typename T = unsigned int>

void ADSR< CONTROL_UPDATE_RATE, LERP_RATE, T >::setDecayLevel ( byte value )

inline

Set the decay level of the ADSR.

Parameters

value the decay level.

Definition at line 213 of file ADSR.h.

◆ setDecayTime()

template<unsigned int CONTROL_UPDATE_RATE, unsigned int LERP_RATE, typename T = unsigned int>

void ADSR< CONTROL_UPDATE_RATE, LERP_RATE, T >::setDecayTime ( unsigned int msec )

inline

Set the decay time of the ADSR in milliseconds.

The actual time taken will be resolved within the resolution of CONTROL_RATE.

Parameters

msec	the unsigned int decay time in milliseconds.

Note: Beware of low values (less than 20 or so, depending on how many steps are being taken), in case internal step size gets calculated as 0, which would mean nothing happens.

Definition at line 300 of file ADSR.h.

◆ setDecayUpdateSteps()

template<unsigned int CONTROL_UPDATE_RATE, unsigned int LERP_RATE, typename T = unsigned int>

void ADSR< CONTROL_UPDATE_RATE, LERP_RATE, T >::setDecayUpdateSteps ( unsigned int steps )

inline

Set the decay time of the ADSR, expressed as the number of update steps (not ADSR::next() interpolation steps) in the decay phase.

Parameters

steps the number of times ADSR::update() will be called in the decay phase.

Definition at line 376 of file ADSR.h.

◆ setLevels()

template<unsigned int CONTROL_UPDATE_RATE, unsigned int LERP_RATE, typename T = unsigned int>

void ADSR< CONTROL_UPDATE_RATE, LERP_RATE, T >::setLevels	(	byte	attack,
		byte	decay,
		byte	sustain,
		byte	release
	)

inline

Set the attack, decay, sustain and release levels.

Parameters

attack	the new attack level.
decay	the new sustain level.
attack	the new sustain level.
decay	the new release level.

Definition at line 270 of file ADSR.h.

◆ setReleaseLevel()

template<unsigned int CONTROL_UPDATE_RATE, unsigned int LERP_RATE, typename T = unsigned int>

void ADSR< CONTROL_UPDATE_RATE, LERP_RATE, T >::setReleaseLevel ( byte value )

inline

Set the release level of the ADSR.

Normally you'd make this 0, but you have the option of some other value.

Parameters

value the release level (usually 0).

Definition at line 234 of file ADSR.h.

◆ setReleaseTime()

template<unsigned int CONTROL_UPDATE_RATE, unsigned int LERP_RATE, typename T = unsigned int>

void ADSR< CONTROL_UPDATE_RATE, LERP_RATE, T >::setReleaseTime ( unsigned int msec )

inline

Set the release time of the ADSR in milliseconds.

The actual time taken will be resolved within the resolution of CONTROL_RATE.

Parameters

msec	the unsigned int release time in milliseconds.

Note: Beware of low values (less than 20 or so, depending on how many steps are being taken), in case internal step size gets calculated as 0, which would mean nothing happens.

Definition at line 328 of file ADSR.h.

◆ setReleaseUpdateSteps()

template<unsigned int CONTROL_UPDATE_RATE, unsigned int LERP_RATE, typename T = unsigned int>

void ADSR< CONTROL_UPDATE_RATE, LERP_RATE, T >::setReleaseUpdateSteps ( unsigned int steps )

inline

Set the release time of the ADSR, expressed as the number of update steps (not ADSR::next() interpolation steps) in the release phase.

Parameters

steps the number of times ADSR::update() will be called in the release phase.

Definition at line 396 of file ADSR.h.

◆ setSustainLevel()

template<unsigned int CONTROL_UPDATE_RATE, unsigned int LERP_RATE, typename T = unsigned int>

void ADSR< CONTROL_UPDATE_RATE, LERP_RATE, T >::setSustainLevel ( byte value )

inline

Set the sustain level of the ADSR.

Parameters

value the sustain level. Usually the same as the decay level, for a steady sustained note.

Definition at line 224 of file ADSR.h.

◆ setSustainTime()

template<unsigned int CONTROL_UPDATE_RATE, unsigned int LERP_RATE, typename T = unsigned int>

void ADSR< CONTROL_UPDATE_RATE, LERP_RATE, T >::setSustainTime ( unsigned int msec )

inline

Set the sustain time of the ADSR in milliseconds.

The actual time taken will be resolved within the resolution of CONTROL_RATE. The sustain phase will finish if the ADSR recieves a noteOff().

Parameters

msec	the unsigned int sustain time in milliseconds.

Note: Beware of low values (less than 20 or so, depending on how many steps are being taken), in case internal step size gets calculated as 0, which would mean nothing happens.

Definition at line 314 of file ADSR.h.

◆ setSustainUpdateSteps()

template<unsigned int CONTROL_UPDATE_RATE, unsigned int LERP_RATE, typename T = unsigned int>

void ADSR< CONTROL_UPDATE_RATE, LERP_RATE, T >::setSustainUpdateSteps ( unsigned int steps )

inline

Set the sustain time of the ADSR, expressed as the number of update steps (not ADSR::next() interpolation steps) in the sustain phase.

Parameters

steps the number of times ADSR::update() will be called in the sustain phase.

Definition at line 386 of file ADSR.h.

◆ setTimes()

template<unsigned int CONTROL_UPDATE_RATE, unsigned int LERP_RATE, typename T = unsigned int>

void ADSR< CONTROL_UPDATE_RATE, LERP_RATE, T >::setTimes	(	unsigned int	attack_ms,
		unsigned int	decay_ms,
		unsigned int	sustain_ms,
		unsigned int	release_ms
	)

inline

Set the attack, decay and release times of the ADSR in milliseconds.

The actual times will be resolved within the resolution of CONTROL_RATE.

Parameters

attack_ms	the new attack time in milliseconds.
decay_ms	the new decay time in milliseconds.
sustain_ms	the new sustain time in milliseconds.
release_ms	the new release time in milliseconds.

Note: Beware of low values (less than 20 or so, depending on how many steps are being taken), in case internal step size gets calculated as 0, which would mean nothing happens.

Definition at line 351 of file ADSR.h.

◆ update()

template<unsigned int CONTROL_UPDATE_RATE, unsigned int LERP_RATE, typename T = unsigned int>

void ADSR< CONTROL_UPDATE_RATE, LERP_RATE, T >::update ( )

inline

Updates the internal controls of the ADSR.

Call this in updateControl().

Definition at line 132 of file ADSR.h.

Public Member Functions

Public Attributes

Detailed Description

template<unsigned int CONTROL_UPDATE_RATE, unsigned int LERP_RATE, typename T = unsigned int> class ADSR< CONTROL_UPDATE_RATE, LERP_RATE, T >

Member Function Documentation

◆ next()

◆ noteOff()

◆ noteOn()

◆ playing()

◆ setADLevels()

◆ setAllUpdateSteps()

◆ setAttackLevel()

◆ setAttackTime()

◆ setAttackUpdateSteps()

◆ setDecayLevel()

◆ setDecayTime()

◆ setDecayUpdateSteps()

◆ setLevels()

◆ setReleaseLevel()

◆ setReleaseTime()

◆ setReleaseUpdateSteps()

◆ setSustainLevel()

◆ setSustainTime()

◆ setSustainUpdateSteps()

◆ setTimes()

◆ update()

template<unsigned int CONTROL_UPDATE_RATE, unsigned int LERP_RATE, typename T = unsigned int>
class ADSR< CONTROL_UPDATE_RATE, LERP_RATE, T >