au.FocusData.InitializeFocusFactorOnFirstUpdate

au.FocusData.InitializeFocusFactorOnFirstUpdate

#Overview

name: au.FocusData.InitializeFocusFactorOnFirstUpdate

This variable is created as a Console Variable (cvar).

It is referenced in 3 C++ source files.

#Summary

#Usage in the C++ source code

The purpose of au.FocusData.InitializeFocusFactorOnFirstUpdate is to control the initialization behavior of the focus factor in Unreal Engine’s audio system. This setting variable is used to determine whether the focus factor should be set to its proper value immediately on the first update or if it should interpolate from 0 to the proper value.

This setting variable is primarily used in the Engine module, specifically within the audio subsystem. It affects the behavior of active sounds and their focus-related properties.

The value of this variable is set using a console variable (CVar) system. It is initialized to 1 (enabled) by default, but can be changed at runtime or through configuration files.

The associated variable InitializeFocusFactorOnFirstUpdateCVar directly interacts with au.FocusData.InitializeFocusFactorOnFirstUpdate. They share the same value, with InitializeFocusFactorOnFirstUpdateCVar being the actual integer variable used in the code.

Developers must be aware that changing this variable can affect the initial behavior of sound focus in the game. When enabled (set to 1), it will immediately set the focus factor to the correct value on the first update, which can be beneficial for accuracy but might cause sudden changes in audio. When disabled (set to 0), it will gradually interpolate the focus factor from 0 to the proper value, which might be more suitable for smooth transitions but could lead to a brief period of incorrect focus at the start.

Best practices when using this variable include:

  1. Consider the impact on game audio when changing this setting, as it can affect the player’s initial audio experience.
  2. Test thoroughly with both settings to determine which provides the best audio experience for your specific game.
  3. Document any changes to this setting in your project, as it may impact audio behavior across the game.

Regarding the associated variable InitializeFocusFactorOnFirstUpdateCVar:

The purpose of InitializeFocusFactorOnFirstUpdateCVar is to serve as the actual integer storage for the au.FocusData.InitializeFocusFactorOnFirstUpdate setting. It is used directly in the code to control the behavior of focus factor initialization.

This variable is used in the Engine module, specifically in the ActiveSound.cpp file, which is part of the audio system.

The value of InitializeFocusFactorOnFirstUpdateCVar is set through the CVar system, initialized to 1 by default.

It directly interacts with au.FocusData.InitializeFocusFactorOnFirstUpdate, as they share the same value.

Developers should be aware that this variable is the one actually checked in the code logic, specifically in the UpdateFocusData function of the FActiveSound class.

Best practices for using this variable include:

  1. Avoid modifying this variable directly in code; instead, use the CVar system to change its value.
  2. When debugging focus-related audio issues, check the value of this variable to understand the current initialization behavior.
  3. Consider exposing this setting in your game’s audio options if you want to give users control over this behavior.

#References in C++ code

#Callsites

This variable is referenced in the following C++ source code:

#Loc: <Workspace>/Engine/Source/Runtime/Engine/Private/ActiveSound.cpp:39

Scope: file

Source code excerpt:

static int32 InitializeFocusFactorOnFirstUpdateCVar = 1;
FAutoConsoleVariableRef CVarInitializeFocusFactorOnFirstUpdateCVar(
	TEXT("au.FocusData.InitializeFocusFactorOnFirstUpdate"),
	InitializeFocusFactorOnFirstUpdateCVar,
	TEXT("When set to 1, focus factor will be initialized on first update to the proper value, instead of interpolating from 0 to the proper value.\n")
	TEXT("0: Disabled, 1: Enabled (default)"),
	ECVF_Default);

FTraceDelegate FActiveSound::ActiveSoundTraceDelegate;

#Associated Variable and Callsites

This variable is associated with another variable named InitializeFocusFactorOnFirstUpdateCVar. They share the same value. See the following C++ source code.

#Loc: <Workspace>/Engine/Source/Runtime/Engine/Private/ActiveSound.cpp:37

Scope: file

Source code excerpt:

	ECVF_Default);

static int32 InitializeFocusFactorOnFirstUpdateCVar = 1;
FAutoConsoleVariableRef CVarInitializeFocusFactorOnFirstUpdateCVar(
	TEXT("au.FocusData.InitializeFocusFactorOnFirstUpdate"),
	InitializeFocusFactorOnFirstUpdateCVar,
	TEXT("When set to 1, focus factor will be initialized on first update to the proper value, instead of interpolating from 0 to the proper value.\n")
	TEXT("0: Disabled, 1: Enabled (default)"),
	ECVF_Default);

FTraceDelegate FActiveSound::ActiveSoundTraceDelegate;
TMap<FTraceHandle, FActiveSound::FAsyncTraceDetails> FActiveSound::TraceToActiveSoundMap;

#Loc: <Workspace>/Engine/Source/Runtime/Engine/Private/ActiveSound.cpp:1606

Scope (from outer to inner):

file
function     void FActiveSound::UpdateFocusData

Source code excerpt:

	// Enabling InitializeFocusVolumeBeforeInterpCVar will fix a bug related to focus factor always needing to interpolate up from 0 to the correct value.
	// Could affect game mix, so enable with caution.
	const bool bShouldInterpolateFocusFactor = (!FocusDataToUpdate->bFirstFocusUpdate || !InitializeFocusFactorOnFirstUpdateCVar);

	// User opt-in for focus interpolation
	if (ListenerData.AttenuationSettings->bEnableFocusInterpolation && bShouldInterpolateFocusFactor)
	{
		// Determine which interpolation speed to use (attack/release)
		float InterpSpeed;