Listening for Attribute Changes

Source/Aura/Private/AbilitySystem/AuraAttributeSet.cpp

@@ -6,9 +6,9 @@
 
 UAuraAttributeSet::UAuraAttributeSet()
 {
-	InitHealth(100.f);
+	InitHealth(50.f);
 	InitMaxHealth(100.f);
-	InitMana(50.f);
+	InitMana(25.f);
 	InitMaxMana(50.f);
 }
 

Source/Aura/Private/Character/AuraCharacter.cpp

@@ -7,7 +7,9 @@
 #include "Camera/CameraComponent.h"
 #include "GameFramework/CharacterMovementComponent.h"
 #include "GameFramework/SpringArmComponent.h"
+#include "Player/AuraPlayerController.h"
 #include "Player/AuraPlayerState.h"
+#include "UI/HUD/AuraHUD.h"
 
 AAuraCharacter::AAuraCharacter()
 {
@@ -36,6 +38,8 @@ void AAuraCharacter::PossessedBy(AController* NewController)
 
 	// Init ability actor info for the Server
 	InitAbilityActorInfo();
+
+	InitHUD();
 }
 
 void AAuraCharacter::OnRep_PlayerState()
@@ -44,6 +48,8 @@ void AAuraCharacter::OnRep_PlayerState()
 
 	// Init ability actor info for the Client
 	InitAbilityActorInfo();
+
+	InitHUD();
 }
 
 void AAuraCharacter::InitAbilityActorInfo()
@@ -55,3 +61,13 @@ void AAuraCharacter::InitAbilityActorInfo()
 	AttributeSet = AuraPlayerState->GetAttributeSet();
 }
 
+void AAuraCharacter::InitHUD() const
+{
+	const auto AuraPlayerState = GetPlayerState<AAuraPlayerState>();
+	check(AuraPlayerState);
+	
+	if(const auto AuraPlayerController = Cast<AAuraPlayerController>(GetController()))
+		if(const auto HUD = Cast<AAuraHUD>(AuraPlayerController->GetHUD()))
+			HUD->InitOverlay(AuraPlayerController, AuraPlayerState, AbilitySystemComponent, AttributeSet);
+}
+

Source/Aura/Private/Player/AuraPlayerController.cpp

@@ -23,9 +23,8 @@ void AAuraPlayerController::BeginPlay()
 	Super::BeginPlay();
 	check(AuraContext);
 
-	UEnhancedInputLocalPlayerSubsystem* Subsystem = ULocalPlayer::GetSubsystem<UEnhancedInputLocalPlayerSubsystem>(GetLocalPlayer());
-	check(Subsystem);
-	Subsystem->AddMappingContext(AuraContext, 0);
+	if(UEnhancedInputLocalPlayerSubsystem* Subsystem = ULocalPlayer::GetSubsystem<UEnhancedInputLocalPlayerSubsystem>(GetLocalPlayer()))
+		Subsystem->AddMappingContext(AuraContext, 0);
 
 	bShowMouseCursor = true;
 	DefaultMouseCursor = EMouseCursor::Default;

Source/Aura/Private/UI/HUD/AuraHUD.cpp

@@ -0,0 +1,37 @@
+// Assets provided by DruidMechanics. Copyright Jonathan Rampersad 2024
+
+
+#include "UI/HUD/AuraHUD.h"
+
+#include "UI/Widget/AuraUserWidget.h"
+#include "Blueprint/UserWidget.h"
+#include "UI/WidgetController/OverlayWidgetController.h"
+
+UOverlayWidgetController* AAuraHUD::GetOverlayWidgetController(const FWidgetControllerParams& WCParams)
+{
+	if (OverlayWidgetController != nullptr) return OverlayWidgetController;
+	
+	OverlayWidgetController = NewObject<UOverlayWidgetController>(this, OverlayWidgetControllerClass);
+	OverlayWidgetController->SetWidgetControllerParams(WCParams);
+
+	OverlayWidgetController->BindCallbacksToDependencies();
+	return OverlayWidgetController;
+}
+
+void AAuraHUD::InitOverlay(APlayerController* PC, APlayerState* PS, UAbilitySystemComponent* ASC, UAttributeSet* AS)
+{
+	checkf(OverlayWidgetClass, TEXT("Overlay Widget Class uninitialized, please fill out BP_AuraHUD"))
+	checkf(OverlayWidgetControllerClass, TEXT("Overlay Widget Controller Class uninitialized, please fill out BP_AuraHUD"))
+	
+	UUserWidget* Widget = CreateWidget<UUserWidget>(GetWorld(), OverlayWidgetClass);
+	OverlayWidget = Cast<UAuraUserWidget>(Widget);
+
+	const FWidgetControllerParams WidgetControllerParams(PC, PS, ASC, AS);
+	const auto WidgetController = GetOverlayWidgetController(WidgetControllerParams);
+
+	OverlayWidget->SetWidgetController(WidgetController);
+	WidgetController->BroadcastInitialValues();
+	
+	Widget->AddToViewport();
+}
+

Source/Aura/Private/UI/WidgetController/AuraWidgetController.cpp

@@ -3,3 +3,18 @@
 
 #include "UI/WidgetController/AuraWidgetController.h"
 
+void UAuraWidgetController::SetWidgetControllerParams(const FWidgetControllerParams& Params)
+{
+	PlayerController = Params.PlayerController;
+	PlayerState = Params.PlayerState;
+	AbilitySystemComponent = Params.AbilitySystemComponent;
+	AttributeSet = Params.AttributeSet;
+}
+
+void UAuraWidgetController::BroadcastInitialValues()
+{
+}
+
+void UAuraWidgetController::BindCallbacksToDependencies()
+{
+}

Source/Aura/Private/UI/WidgetController/OverlayWidgetController.cpp

@@ -0,0 +1,52 @@
+// Assets provided by DruidMechanics. Copyright Jonathan Rampersad 2024
+
+
+#include "UI/WidgetController/OverlayWidgetController.h"
+
+#include "AbilitySystem/AuraAttributeSet.h"
+
+void UOverlayWidgetController::BroadcastInitialValues()
+{
+	const auto AuraAttributeSet = CastChecked<UAuraAttributeSet>(AttributeSet);
+	OnHealthChanged.Broadcast(AuraAttributeSet->GetHealth());
+	OnMaxHealthChanged.Broadcast(AuraAttributeSet->GetMaxHealth());
+	OnManaChanged.Broadcast(AuraAttributeSet->GetMana());
+	OnMaxManaChanged.Broadcast(AuraAttributeSet->GetMaxMana());
+}
+
+void UOverlayWidgetController::BindCallbacksToDependencies()
+{
+	const UAuraAttributeSet* AuraAttributeSet = CastChecked<UAuraAttributeSet>(AttributeSet);
+
+	AbilitySystemComponent->GetGameplayAttributeValueChangeDelegate(
+		AuraAttributeSet->GetHealthAttribute()).AddUObject(this, &UOverlayWidgetController::HealthChanged);
+
+	AbilitySystemComponent->GetGameplayAttributeValueChangeDelegate(
+		AuraAttributeSet->GetMaxHealthAttribute()).AddUObject(this, &UOverlayWidgetController::MaxHealthChanged);
+
+	AbilitySystemComponent->GetGameplayAttributeValueChangeDelegate(
+		AuraAttributeSet->GetManaAttribute()).AddUObject(this, &UOverlayWidgetController::ManaChanged);
+
+	AbilitySystemComponent->GetGameplayAttributeValueChangeDelegate(
+		AuraAttributeSet->GetMaxManaAttribute()).AddUObject(this, &UOverlayWidgetController::MaxManaChanged);
+}
+
+void UOverlayWidgetController::HealthChanged(const FOnAttributeChangeData& Data) const
+{
+	OnHealthChanged.Broadcast(Data.NewValue);
+}
+
+void UOverlayWidgetController::MaxHealthChanged(const FOnAttributeChangeData& Data) const
+{
+	OnMaxHealthChanged.Broadcast(Data.NewValue);
+}
+
+void UOverlayWidgetController::ManaChanged(const FOnAttributeChangeData& Data) const
+{
+	OnManaChanged.Broadcast(Data.NewValue);
+}
+
+void UOverlayWidgetController::MaxManaChanged(const FOnAttributeChangeData& Data) const
+{
+	OnMaxManaChanged.Broadcast(Data.NewValue);
+}

Source/Aura/Public/Character/AuraCharacter.h

@@ -31,4 +31,6 @@ public:
 
 private:
 	void InitAbilityActorInfo();
+
+	void InitHUD() const;
 };

Source/Aura/Public/UI/HUD/AuraHUD.h

@@ -0,0 +1,39 @@
+// Assets provided by DruidMechanics. Copyright Jonathan Rampersad 2024
+
+#pragma once
+
+#include "CoreMinimal.h"
+#include "GameFramework/HUD.h"
+#include "AuraHUD.generated.h"
+
+class UAttributeSet;
+class UAbilitySystemComponent;
+struct FWidgetControllerParams;
+class UOverlayWidgetController;
+class UAuraUserWidget;
+/**
+ * 
+ */
+UCLASS()
+class AURA_API AAuraHUD : public AHUD
+{
+	GENERATED_BODY()
+
+public:
+	UPROPERTY()
+	TObjectPtr<UAuraUserWidget> OverlayWidget;
+
+	UOverlayWidgetController* GetOverlayWidgetController(const FWidgetControllerParams& WCParams);
+
+	void InitOverlay(APlayerController* PC, APlayerState* PS, UAbilitySystemComponent* ASC, UAttributeSet* AS);
+	
+private:
+	UPROPERTY(EditAnywhere)
+	TSubclassOf<UAuraUserWidget> OverlayWidgetClass;
+
+	UPROPERTY()
+	TObjectPtr<UOverlayWidgetController> OverlayWidgetController;
+
+	UPROPERTY(EditAnywhere)
+	TSubclassOf<UOverlayWidgetController> OverlayWidgetControllerClass;
+};

Source/Aura/Public/UI/WidgetController/AuraWidgetController.h

@@ -3,11 +3,36 @@
 #pragma once
 
 #include "CoreMinimal.h"
+#include "AbilitySystemComponent.h"
 #include "UObject/NoExportTypes.h"
 #include "AuraWidgetController.generated.h"
 
 class UAttributeSet;
 class UAbilitySystemComponent;
+
+USTRUCT(BlueprintType)
+struct FWidgetControllerParams
+{
+	GENERATED_BODY()
+
+	FWidgetControllerParams() {}
+	FWidgetControllerParams(APlayerController* PC, APlayerState* PS, UAbilitySystemComponent* ASC, UAttributeSet* AS)
+	: PlayerController(PC), PlayerState(PS), AbilitySystemComponent(ASC), AttributeSet(AS)
+	{}
+
+	UPROPERTY(EditAnywhere, BlueprintReadWrite)
+	TObjectPtr<APlayerController> PlayerController = nullptr;
+
+	UPROPERTY(EditAnywhere, BlueprintReadWrite)
+	TObjectPtr<APlayerState> PlayerState = nullptr;
+
+	UPROPERTY(EditAnywhere, BlueprintReadWrite)
+	TObjectPtr<UAbilitySystemComponent> AbilitySystemComponent = nullptr;
+
+	UPROPERTY(EditAnywhere, BlueprintReadWrite)
+	TObjectPtr<UAttributeSet> AttributeSet = nullptr;
+};
+
 /**
  * 
  */
@@ -16,6 +41,12 @@ class AURA_API UAuraWidgetController : public UObject
 {
 	GENERATED_BODY()
 
+public:
+	UFUNCTION(BlueprintCallable)
+	void SetWidgetControllerParams(const FWidgetControllerParams& Params);
+
+	virtual void BroadcastInitialValues(); 
+	virtual void BindCallbacksToDependencies();
 protected:
 	UPROPERTY(BlueprintReadOnly, Category="WidgetController")
 	TObjectPtr<APlayerController> PlayerController;

Source/Aura/Public/UI/WidgetController/OverlayWidgetController.h

@@ -0,0 +1,44 @@
+// Assets provided by DruidMechanics. Copyright Jonathan Rampersad 2024
+
+#pragma once
+
+#include "CoreMinimal.h"
+#include "UI/WidgetController/AuraWidgetController.h"
+#include "OverlayWidgetController.generated.h"
+
+DECLARE_DYNAMIC_MULTICAST_DELEGATE_OneParam(FOnHealthChangedSignature, float, NewHealth);
+DECLARE_DYNAMIC_MULTICAST_DELEGATE_OneParam(FOnMaxHealthChangedSignature, float, NewMaxHealth);
+DECLARE_DYNAMIC_MULTICAST_DELEGATE_OneParam(FOnManaChangedSignature, float, NewMana);
+DECLARE_DYNAMIC_MULTICAST_DELEGATE_OneParam(FOnMaxManaChangedSignature, float, NewMaxMana);
+
+
+/**
+ * 
+ */
+UCLASS(BlueprintType, Blueprintable)
+class AURA_API UOverlayWidgetController : public UAuraWidgetController
+{
+	GENERATED_BODY()
+
+public:
+	virtual void BroadcastInitialValues() override;
+	virtual void BindCallbacksToDependencies() override;
+
+	UPROPERTY(BlueprintAssignable, Category="GAS|Attributes")
+	FOnHealthChangedSignature OnHealthChanged;
+
+	UPROPERTY(BlueprintAssignable, Category="GAS|Attributes")
+	FOnMaxHealthChangedSignature OnMaxHealthChanged;
+
+	UPROPERTY(BlueprintAssignable, Category="GAS|Attributes")
+	FOnManaChangedSignature OnManaChanged;
+
+	UPROPERTY(BlueprintAssignable, Category="GAS|Attributes")
+	FOnMaxManaChangedSignature OnMaxManaChanged;
+
+protected:
+	void HealthChanged(const FOnAttributeChangeData& Data) const;
+	void MaxHealthChanged(const FOnAttributeChangeData& Data) const;
+	void ManaChanged(const FOnAttributeChangeData& Data) const;
+	void MaxManaChanged(const FOnAttributeChangeData& Data) const;
+};