Unreal Enhanced Input

Wire player input the modern UE5 way with the Enhanced Input system: data-driven Input Actions and Mapping Contexts instead of the legacy Project Settings axis/action mappings. Targets UE 5.8 (Enhanced Input is the default; legacy input is deprecated).

When to use

• Use when adding movement/look/jump/fire input, creating Input Action (IA_) and Input Mapping Context (IMC_) assets, applying modifiers/triggers, adding a mapping context to a player, or binding actions in C++ or Blueprints.
• Use when the project has IA_*/IMC_* assets or references EnhancedInput.

When not to use: engine-agnostic input architecture (rebinding strategy, buffering, multi-device design) → input-systems. The Pawn/Character C++ those bindings live in → unreal-cpp-gameplay.

Core workflow

1. Enable the module/plugin. Enhanced Input is on by default in UE5; for C++ binding add "EnhancedInput" to PublicDependencyModuleNames in *.Build.cs.
2. Create Input Actions (IA_). Each has a Value Type: Digital (bool) for buttons, Axis1D (float) for triggers, Axis2D (Vector2D) for movement/look.
3. Create an Input Mapping Context (IMC_) that maps keys/buttons to those actions. Use Modifiers to shape raw input (Negate, Swizzle Input Axis Values, Dead Zone) — e.g. WASD into one Axis2D needs Negate on A/S and a Swizzle on W/S. Use Triggers (Pressed, Hold, Tap) to decide when an action fires. The Combo trigger is deprecated in UE 5.8; don't build new input on it.
4. Add the mapping context to the player via the EnhancedInputLocalPlayerSubsystem (AddMappingContext(IMC, Priority)), usually in BeginPlay/possession.
5. Bind actions to handlers by ETriggerEvent (Triggered, Started, Completed, …) on the EnhancedInputComponent, and read the FInputActionValue in the handler.
6. Verify in PIE; the Enhanced Input debugging console commands (showdebug enhancedinput) show which actions trigger and their values.

Patterns

1. Add the mapping context (C++ Character)

void AMyCharacter::BeginPlay()
{
    Super::BeginPlay();
    if (APlayerController* PC = Cast<APlayerController>(GetController()))
        if (ULocalPlayer* LP = PC->GetLocalPlayer())
            if (auto* Subsystem = LP->GetSubsystem<UEnhancedInputLocalPlayerSubsystem>())
                Subsystem->AddMappingContext(DefaultMappingContext, /*Priority*/ 0);
}
// DefaultMappingContext is a UPROPERTY(EditAnywhere) TObjectPtr<UInputMappingContext>.

2. Bind actions and read values

void AMyCharacter::SetupPlayerInputComponent(UInputComponent* PlayerInputComponent)
{
    Super::SetupPlayerInputComponent(PlayerInputComponent);

    // The component is an Enhanced Input component when the plugin is active.
    // (Don't name the parameter InputComponent: that shadows AActor::InputComponent.)
    if (UEnhancedInputComponent* EIC = Cast<UEnhancedInputComponent>(PlayerInputComponent))
    {
        EIC->BindAction(MoveAction, ETriggerEvent::Triggered, this, &AMyCharacter::Move);
        EIC->BindAction(LookAction, ETriggerEvent::Triggered, this, &AMyCharacter::Look);
        EIC->BindAction(JumpAction, ETriggerEvent::Started,   this, &ACharacter::Jump);
        EIC->BindAction(JumpAction, ETriggerEvent::Completed, this, &ACharacter::StopJumping);
    }
}

void AMyCharacter::Move(const FInputActionValue& Value)
{
    const FVector2D Axis = Value.Get<FVector2D>();          // Axis2D action
    AddMovementInput(GetActorForwardVector(), Axis.Y);
    AddMovementInput(GetActorRightVector(),   Axis.X);
}

3. Blueprint equivalent (node flow)

Event BeginPlay
  -> Get Controller -> Cast To PlayerController -> Get Local Player
  -> Get EnhancedInputLocalPlayerSubsystem -> Add Mapping Context (IMC_Default, Priority 0)

// IA_Move is exposed as its own event node in the Character's Event Graph:
EnhancedInputAction IA_Move (Triggered)
  -> Action Value (Vector2D) -> Add Movement Input (Forward * Y, Right * X)

Pitfalls

• No input at all — the mapping context was never added (AddMappingContext), or the player has no Local Player yet. Add it after possession/BeginPlay.
• Input works in single player but not on a client, or stops after respawn — BeginPlay ran before the controller possessed the pawn, so GetController() was null. Add the context in an override of PawnClientRestart(), which runs on the owning client after possession (Epic's Input Overview does this), or in the PlayerController.
• Link/compile error binding in C++ — "EnhancedInput" isn't in Build.cs PublicDependencyModuleNames.
• WASD only moves on two keys / wrong axis — Axis2D needs Modifiers: Negate on the negative keys (A, S) and a Swizzle Input Axis Values on the vertical (W/S) so both axes map correctly. Raw bindings without modifiers misbehave.
• Get<FVector2D>() returns zero — value-type mismatch: the Input Action is Digital/Axis1D, not Axis2D. Match the Get<T>() to the action's Value Type.
• Action fires every frame unexpectedly — Triggered repeats while held for a Down trigger; use Started/Completed for one-shots (jump press/release), or a Pressed/Tap trigger.
• Two contexts fight — multiple mapping contexts stack by Priority; a higher-priority context can consume a key. Manage with priorities and RemoveMappingContext.

References

• For a complete first-/third-person C++ Character with Enhanced Input (header + source, including look/jump and a control-rebind note), read references/cpp-setup.md.
• Primary docs: "Enhanced Input in Unreal Engine" (https://dev.epicgames.com/documentation/en-us/unreal-engine/enhanced-input-in-unreal-engine) and "Input Overview" (https://dev.epicgames.com/documentation/en-us/unreal-engine/input-overview-in-unreal-engine).

Related skills

• input-systems — engine-agnostic input architecture and rebinding strategy.
• unreal-cpp-gameplay — the Character/Pawn class and module setup.
• fps-shooter — composes input with a 3D controller and shooting.