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> Unreal Engine API Reference > Runtime > SignalProcessing > DSP > FEnvelope

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FEnvelope

Envelope class generates ADSR style envelope.

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References

Module	SignalProcessing
Header	/Engine/Source/Runtime/SignalProcessing/Public/DSP/Envelope.h
Include	#include "DSP/Envelope.h"

Syntax

class FEnvelope

Remarks

Envelope class generates ADSR style envelope.

Variables

	Name	Description
FEnvData	AttackData
float	AttackTimeMSec
uint8: 1	bBiasInvert	Bias output inversions.
uint8: 1	bChanged	Whether or not this envelope has changed and needs to have values recomputed.
uint8: 1	bCurrentCycleIsADOnly	Tracks if the current envelope was started with sustain at 0.0 (avoids bug where sustain being turned up during decay phase makes hang)
float	BiasDepth
FPatchSource	BiasedEnvSource
uint8: 1	bInvert	Inverts the output.
uint8: 1	bIsLegatoMode	Whether or not the envelope is reset back to attack when started.
uint8: 1	bIsRetriggerMode	Whether or not the envelope value is set to zero when finished.
uint8: 1	bIsSimulatingAnalog	Whether or not we want to simulate analog behavior.
float	CurrentEnvelopeBiasValue
float	CurrentEnvelopeValue
EEnvelopeState	CurrentState
FEnvData	DecayData
float	DecayTimeMsec
float	Depth
FPatchSource	EnvSource
FModulationMatr...	ModMatrix	Mod matrix.
float	OutputGain
FEnvData	ReleaseData
float	ReleaseTimeMsec
float	SampleRate
float	ShutdownDelta
float	ShutdownTimeMsec
float	SustainGain
int32	VoiceId	The current envelope value, used to compute exponential envelope curves.

Constructors

	Name	Description
	FEnvelope()

Destructors

	Name	Description
	~FEnvelope()

Functions

	Name	Description
float	Generate ( float* BiasedOutput )	Generate the next output value of the envelope.
const FPatch...	GetModSourceBiasEnv()
const FPatch...	GetModSourceEnv()	Get the envelope's patch nodes.
void	Init ( const float InSampleRate, const int32 InVoiceId, FModulationMatrix* InModMatrix, const bool bInSimulateAnalog )	Initialize the envelope with the given sample rate.
bool	IsDone()	Queries if the envelope has finished.
bool	IsRetrigger()
void	Kill()	Kills the envelope (will cause discontinuity)
void	Reset()	Resets the envelope.
void	SetAttackTime ( const float InAttackTimeMsec )	Sets the envelope attack time in msec.
void	SetBiasDepth ( const float InDepth )	Sets the depth of the bias output.
void	SetBiasInvert ( const bool bInBiasInvert )	Inverts the value of the biased envelope output.
void	SetDecayTime ( const float InDecayTimeMsec )	Sets the envelope decay time in msec.
void	SetDepth ( const float InDepth )	Sets the envelope depth.
void	SetInvert ( const bool bInInvert )	Inverts the value of envelope output.
void	SetLegato ( const bool bInLegatoMode )	Sets whether the envelope is in legato mode. Legato mode doesn't restart the envelope if it's already playing.
void	SetReleaseTime ( const float InReleaseTimeMsec )	Sets the envelope release time in msec.
void	SetRetrigger ( const bool bInRetrigger )	Sets whether or not the envelope is zero'd when reset.
void	SetSimulateAnalog ( const bool bInSimulatingAnalog )	Sets the envelope mode.
void	SetSustainGain ( const float InSustainGain )	Sets the envelope sustain gain in linear gain values.
void	Shutdown()	Puts envelope into shutdown mode, which is a much faster cutoff than release, but avoids pops.
void	Start()	Start the envelope, puts envelope in attack state.
void	StartLegato()
void	StartLegato ( const float InNewDepth )	For truly legato envelope logic, we need to know the new sustain gain (if its being changed).
void	Stop()	Stop the envelope, puts in the release state. Can optionally force to off state.
void	Update()	Update the state of the envelope.

Classes

	Name	Description
	FEnvData

Enums

	Name	Description
	EEnvelopeState	States for the envelope state machine.

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