Enhanced Input overview

Unreal's modern input stack. Replaces the old Project Settings → Input → Action Mappings table with content-side assets you can swap, layer, and modify at runtime.

For how Rephrased wires input on the player character, see Enhanced Input in Rephrased.

Three asset types

Type	Prefix	Purpose
UInputAction	IA_	A semantic action: "Move", "Jump", "Interact". Has a value type (bool, float, Axis2D, etc.) but no key binding.
UInputMappingContext	IMC_	Maps physical keys/buttons to input actions. Multiple contexts can be active and layered.
UInputModifier / UInputTrigger	varies	Optional: deadzones, swizzles, hold/tap detectors.

At BeginPlay

A pawn or character pushes its mapping context onto the local player's input subsystem. Conceptually:

if (APlayerController* PC = Cast<APlayerController>(GetController()))
{
    if (ULocalPlayer* LP = PC->GetLocalPlayer())
    {
        if (UEnhancedInputLocalPlayerSubsystem* InputSub =
            LP->GetSubsystem<UEnhancedInputLocalPlayerSubsystem>())
        {
            InputSub->AddMappingContext(DefaultMappingContext, 0);
        }
    }
}

After that, the engine routes physical input through the mapping context to the actions, and the action's bound function fires.

Binding actions to functions

In SetupPlayerInputComponent:

UEnhancedInputComponent* EIC = Cast<UEnhancedInputComponent>(PlayerInputComponent);
EIC->BindAction(MoveAction, ETriggerEvent::Triggered, this, &AMyCharacter::Move);
EIC->BindAction(InteractAction, ETriggerEvent::Triggered, this, &AMyCharacter::Interact);

Trigger events:

• ETriggerEvent::Triggered — fires while the action is active (per-frame for axis, on press for buttons depending on triggers).
• ETriggerEvent::Started — first frame of a press.
• ETriggerEvent::Completed — release.
• ETriggerEvent::Canceled — interrupted before completion.

Use Triggered for movement axes, Started for one-shot button presses (jump, interact).

Why this is better than the old system

• Mapping contexts can be layered. The base context for gameplay sits underneath; a UI navigation context can stack on top without rewriting gameplay bindings.
• Modifiers and triggers compose. "Swap WASD on left-handed player" is a modifier on the existing context, not a new code path.
• Rebinding at runtime is straightforward — you mutate the active context, the engine picks it up.

Adding a new action

1. Content browser → Input → Input Action. Name it IA_Foo. Set the value type (Bool, Axis2D, etc.).
2. Open the default mapping context. Add a row, drop in IA_Foo, assign keys/buttons.
3. In your character class, add a UInputAction* field and a handler function (e.g. void DoFoo()).
4. In SetupPlayerInputComponent, bind: EIC->BindAction(FooAction, ETriggerEvent::Started, this, &AMyCharacter::DoFoo);
5. In the Blueprint subclass, assign FooAction = IA_Foo.

Gamepad support

Each IMC_* row can hold both a keyboard key and a gamepad input. The same IA_* is invoked regardless of source.

Change history

• 2026-05-23 — Gabriel Li — Fixed BeginPlay snippet (APlayerController cast before GetLocalPlayer).
• 2026-05-08 — Gabriel Li — Added baseline change history section for weekly wiki maintenance.