UE5 C++ Scaffold Skill

---
name: ue5-cpp-scaffold
description: Generate Unreal Engine 5 C++ class boilerplate following Epic coding standards. Creates Actors, Components, Subsystems, GameplayAbilities, AttributeSets, Widgets, and more with proper UPROPERTY/UFUNCTION macros, include hierarchy, and module API macros. Use whenever creating new UE5 C++ classes, scaffolding gameplay systems, generating header/source pairs, or setting up GAS classes. Also use when the user asks to "create a new Actor", "add a component", "scaffold a gameplay ability", or "make a UE5 class".
---

# UE5 C++ Scaffold Skill

Generates production-quality UE5 C++ header/source file pairs following Epic's coding standard. Handles all the boilerplate — macros, includes, forward declarations, and module API exports.

## How It Works

1. Ask the user what class type they need
2. Gather class name, parent class, and key properties/functions
3. Generate the .h and .cpp files with full boilerplate
4. Place files in the correct Source directory location

## Class Type Templates

### Actor

```cpp
// MyActor.h
#pragma once
#include "CoreMinimal.h"
#include "GameFramework/Actor.h"
#include "MyActor.generated.h"

UCLASS()
class MODULENAME_API AMyActor : public AActor
{
    GENERATED_BODY()

public:
    AMyActor();

protected:
    virtual void BeginPlay() override;
    virtual void Tick(float DeltaTime) override;
};
```

### Character

```cpp
// MyCharacter.h
#pragma once
#include "CoreMinimal.h"
#include "GameFramework/Character.h"
#include "AbilitySystemInterface.h"
#include "MyCharacter.generated.h"

class UAbilitySystemComponent;
class USpringArmComponent;
class UCameraComponent;

UCLASS()
class MODULENAME_API AMyCharacter : public ACharacter, public IAbilitySystemInterface
{
    GENERATED_BODY()

public:
    AMyCharacter();

    virtual UAbilitySystemComponent* GetAbilitySystemComponent() const override;

protected:
    virtual void BeginPlay() override;
    virtual void SetupPlayerInputComponent(UInputComponent* PlayerInputComponent) override;

    UPROPERTY(VisibleAnywhere, BlueprintReadOnly, Category = "Camera")
    TObjectPtr<USpringArmComponent> SpringArmComponent;

    UPROPERTY(VisibleAnywhere, BlueprintReadOnly, Category = "Camera")
    TObjectPtr<UCameraComponent> CameraComponent;

    UPROPERTY(VisibleAnywhere, BlueprintReadOnly, Category = "Abilities")
    TObjectPtr<UAbilitySystemComponent> AbilitySystemComponent;
};
```

### ActorComponent

```cpp
// MyComponent.h
#pragma once
#include "CoreMinimal.h"
#include "Components/ActorComponent.h"
#include "MyComponent.generated.h"

UCLASS(ClassGroup=(Custom), meta=(BlueprintSpawnableComponent))
class MODULENAME_API UMyComponent : public UActorComponent
{
    GENERATED_BODY()

public:
    UMyComponent();

protected:
    virtual void BeginPlay() override;
    virtual void TickComponent(float DeltaTime, ELevelTick TickType, FActorComponentTickFunction* ThisTickFunction) override;
};
```

### SceneComponent

```cpp
// MySceneComponent.h
#pragma once
#include "CoreMinimal.h"
#include "Components/SceneComponent.h"
#include "MySceneComponent.generated.h"

UCLASS(ClassGroup=(Custom), meta=(BlueprintSpawnableComponent))
class MODULENAME_API UMySceneComponent : public USceneComponent
{
    GENERATED_BODY()

public:
    UMySceneComponent();

protected:
    virtual void BeginPlay() override;
};
```

### GameplayAbility (GAS)

```cpp
// GA_MyAbility.h
#pragma once
#include "CoreMinimal.h"
#include "Abilities/GameplayAbility.h"
#include "GA_MyAbility.generated.h"

UCLASS()
class MODULENAME_API UGA_MyAbility : public UGameplayAbility
{
    GENERATED_BODY()

public:
    UGA_MyAbility();

    virtual void ActivateAbility(const FGameplayAbilitySpecHandle Handle,
        const FGameplayAbilityActorInfo* ActorInfo,
        const FGameplayAbilityActivationInfo ActivationInfo,
        const FGameplayEventData* TriggerEventData) override;

    virtual void EndAbility(const FGameplayAbilitySpecHandle Handle,
        const FGameplayAbilityActorInfo* ActorInfo,
        const FGameplayAbilityActivationInfo ActivationInfo,
        bool bReplicateEndAbility, bool bWasCancelled) override;

    virtual bool CanActivateAbility(const FGameplayAbilitySpecHandle Handle,
        const FGameplayAbilityActorInfo* ActorInfo,
        const FGameplayTagContainer* SourceTags = nullptr,
        const FGameplayTagContainer* TargetTags = nullptr,
        OUT FGameplayTagContainer* OptionalRelevantTags = nullptr) const override;

protected:
    UPROPERTY(EditDefaultsOnly, BlueprintReadOnly, Category = "Ability")
    float CooldownDuration = 1.0f;

    UPROPERTY(EditDefaultsOnly, BlueprintReadOnly, Category = "Ability")
    float Cost = 10.0f;
};
```

### AttributeSet (GAS)

```cpp
// MyAttributeSet.h
#pragma once
#include "CoreMinimal.h"
#include "AttributeSet.h"
#include "AbilitySystemComponent.h"
#include "MyAttributeSet.generated.h"

#define ATTRIBUTE_ACCESSORS(ClassName, PropertyName) \
    GAMEPLAYATTRIBUTE_PROPERTY_GETTER(ClassName, PropertyName) \
    GAMEPLAYATTRIBUTE_VALUE_GETTER(PropertyName) \
    GAMEPLAYATTRIBUTE_VALUE_SETTER(PropertyName) \
    GAMEPLAYATTRIBUTE_VALUE_INITTER(PropertyName)

UCLASS()
class MODULENAME_API UMyAttributeSet : public UAttributeSet
{
    GENERATED_BODY()

public:
    UMyAttributeSet();

    virtual void GetLifetimeReplicatedProps(TArray<FLifetimeProperty>& OutLifetimeProps) const override;
    virtual void PreAttributeChange(const FGameplayAttribute& Attribute, float& NewValue) override;
    virtual void PostGameplayEffectExecute(const FGameplayEffectModCallbackData& Data) override;

    UPROPERTY(BlueprintReadOnly, ReplicatedUsing = OnRep_Health, Category = "Attributes")
    FGameplayAttributeData Health;
    ATTRIBUTE_ACCESSORS(UMyAttributeSet, Health)

    UPROPERTY(BlueprintReadOnly, ReplicatedUsing = OnRep_MaxHealth, Category = "Attributes")
    FGameplayAttributeData MaxHealth;
    ATTRIBUTE_ACCESSORS(UMyAttributeSet, MaxHealth)

    UPROPERTY(BlueprintReadOnly, ReplicatedUsing = OnRep_Mana, Category = "Attributes")
    FGameplayAttributeData Mana;
    ATTRIBUTE_ACCESSORS(UMyAttributeSet, Mana)

protected:
    UFUNCTION()
    virtual void OnRep_Health(const FGameplayAttributeData& OldHealth);

    UFUNCTION()
    virtual void OnRep_MaxHealth(const FGameplayAttributeData& OldMaxHealth);

    UFUNCTION()
    virtual void OnRep_Mana(const FGameplayAttributeData& OldMana);
};
```

### GameMode

```cpp
// MyGameMode.h
#pragma once
#include "CoreMinimal.h"
#include "GameFramework/GameModeBase.h"
#include "MyGameMode.generated.h"

UCLASS()
class MODULENAME_API AMyGameMode : public AGameModeBase
{
    GENERATED_BODY()

public:
    AMyGameMode();

    virtual void InitGame(const FString& MapName, const FString& Options, FString& ErrorMessage) override;
    virtual APawn* SpawnDefaultPawnAtTransform_Implementation(AController* NewPlayer, const FTransform& SpawnTransform) override;
};
```

### PlayerController

```cpp
// MyPlayerController.h
#pragma once
#include "CoreMinimal.h"
#include "GameFramework/PlayerController.h"
#include "MyPlayerController.generated.h"

class UInputMappingContext;
class UInputAction;

UCLASS()
class MODULENAME_API AMyPlayerController : public APlayerController
{
    GENERATED_BODY()

public:
    AMyPlayerController();

protected:
    virtual void BeginPlay() override;
    virtual void SetupInputComponent() override;

    UPROPERTY(EditDefaultsOnly, BlueprintReadOnly, Category = "Input")
    TObjectPtr<UInputMappingContext> DefaultMappingContext;
};
```

### Subsystem

```cpp
// MyGameInstanceSubsystem.h
#pragma once
#include "CoreMinimal.h"
#include "Subsystems/GameInstanceSubsystem.h"
#include "MyGameInstanceSubsystem.generated.h"

UCLASS()
class MODULENAME_API UMyGameInstanceSubsystem : public UGameInstanceSubsystem
{
    GENERATED_BODY()

public:
    virtual void Initialize(FSubsystemCollectionBase& Collection) override;
    virtual void Deinitialize() override;

    UFUNCTION(BlueprintCallable, Category = "MySubsystem")
    void DoSomething();
};
```

### UObject (Data Asset)

```cpp
// MyDataAsset.h
#pragma once
#include "CoreMinimal.h"
#include "Engine/DataAsset.h"
#include "MyDataAsset.generated.h"

UCLASS(BlueprintType)
class MODULENAME_API UMyDataAsset : public UPrimaryDataAsset
{
    GENERATED_BODY()

public:
    UPROPERTY(EditDefaultsOnly, BlueprintReadOnly, Category = "Config")
    FName ItemName;

    UPROPERTY(EditDefaultsOnly, BlueprintReadOnly, Category = "Config")
    TObjectPtr<UTexture2D> Icon;

    UPROPERTY(EditDefaultsOnly, BlueprintReadOnly, Category = "Config")
    float BaseValue = 1.0f;

    virtual FPrimaryAssetId GetPrimaryAssetId() const override;
};
```

### Interface

```cpp
// Interactable.h
#pragma once
#include "CoreMinimal.h"
#include "UObject/Interface.h"
#include "Interactable.generated.h"

UINTERFACE(MinimalAPI, Blueprintable)
class UInteractable : public UInterface
{
    GENERATED_BODY()
};

class MODULENAME_API IInteractable
{
    GENERATED_BODY()

public:
    UFUNCTION(BlueprintNativeEvent, BlueprintCallable, Category = "Interaction")
    void Interact(AActor* Caller);

    UFUNCTION(BlueprintNativeEvent, BlueprintCallable, Category = "Interaction")
    FText GetInteractionText() const;
};
```

### AnimInstance (Animation Blueprint Base)

```cpp
// MyAnimInstance.h
#pragma once
#include "CoreMinimal.h"
#include "Animation/AnimInstance.h"
#include "MyAnimInstance.generated.h"

UCLASS()
class MODULENAME_API UMyAnimInstance : public UAnimInstance
{
    GENERATED_BODY()

public:
    virtual void NativeInitializeAnimation() override;
    virtual void NativeUpdateAnimation(float DeltaSeconds) override;

protected:
    UPROPERTY(BlueprintReadOnly, Category = "Movement")
    float Speed = 0.0f;

    UPROPERTY(BlueprintReadOnly, Category = "Movement")
    float Direction = 0.0f;

    UPROPERTY(BlueprintReadOnly, Category = "Movement")
    bool bIsInAir = false;

    UPROPERTY(BlueprintReadOnly, Category = "Movement")
    bool bIsAccelerating = false;
};
```

```cpp
// MyAnimInstance.cpp
#include "MyAnimInstance.h"
#include "GameFramework/Character.h"
#include "GameFramework/CharacterMovementComponent.h"
#include "KismetAnimationLibrary.h"

void UMyAnimInstance::NativeInitializeAnimation()
{
    Super::NativeInitializeAnimation();
}

void UMyAnimInstance::NativeUpdateAnimation(float DeltaSeconds)
{
    Super::NativeUpdateAnimation(DeltaSeconds);

    if (APawn* Pawn = TryGetPawnOwner())
    {
        FVector Velocity = Pawn->GetVelocity();
        Speed = Velocity.Size2D();
        Direction = UKismetAnimationLibrary::CalculateDirection(Velocity, Pawn->GetActorRotation());

        if (ACharacter* Character = Cast<ACharacter>(Pawn))
        {
            bIsInAir = Character->GetCharacterMovement()->IsFalling();
            bIsAccelerating = Character->GetCharacterMovement()->GetCurrentAcceleration().Size() > 0.0f;
        }
    }
}
```

### BlueprintFunctionLibrary (Static Utility Functions)

```cpp
// MyBlueprintFunctionLibrary.h
#pragma once
#include "CoreMinimal.h"
#include "Kismet/BlueprintFunctionLibrary.h"
#include "MyBlueprintFunctionLibrary.generated.h"

UCLASS()
class MODULENAME_API UMyBlueprintFunctionLibrary : public UBlueprintFunctionLibrary
{
    GENERATED_BODY()

public:
    UFUNCTION(BlueprintCallable, Category = "Utilities", meta = (WorldContext = "WorldContextObject"))
    static AActor* FindClosestActorOfClass(const UObject* WorldContextObject, TSubclassOf<AActor> ActorClass, FVector Origin, float MaxDistance = 5000.0f);

    UFUNCTION(BlueprintPure, Category = "Math")
    static FVector GetRandomPointInRadius(FVector Origin, float Radius);

    UFUNCTION(BlueprintCallable, Category = "Utilities")
    static FString FormatTime(float TimeInSeconds);
};
```

## Generation Rules

1. **Replace `MODULENAME`** with the actual module name in uppercase (e.g., `MYPROJECT_API`)
2. **File placement**: Headers in `Source/[Module]/Public/[Category]/`, sources in `Source/[Module]/Private/[Category]/`
3. **Forward declarations** over includes in headers — include only in .cpp
4. **Use `TObjectPtr<>`** for all UObject pointer members
5. **Include `[ClassName].generated.h`** as the LAST include in every header
6. **Match .cpp includes**: Always include the matching header first, then engine headers
7. **Category organization**: Group properties and functions by Category for editor display

## Reference

For the full Epic C++ coding standard, see:
`dev.epicgames.com/documentation/en-us/unreal-engine/epic-cplusplus-coding-standard-for-unreal-engine`

For GAS documentation: `github.com/tranek/GASDocumentation`