虚幻引擎5 GAS开发俯视角RPG游戏 P05-05 游戏效果委托

该技术文档详细介绍了如何在Unreal Engine中实现游戏效果委托绑定系统。核心实现包括：

在UCC_AbilitySystemComponent中声明并绑定多播委托EffectApplied()到OnGameplayEffectAppliedDelegateToSelf，用于监听游戏效果应用事件。
通过AbilityActorInfoSet()方法初始化委托绑定，在角色初始化时调用。
实现效果处理逻辑：当效果被应用时，从FGameplayEffectSpec获取所有AssetTag并打印到屏幕。
在英雄角色(CC_HeroCharacter)和敌人角色(CC_EnemyCharacter)中分别实现初始化逻辑，确保服务器和客户端都能正确初始化能力系统组件并绑定委托。

该方案实现了游戏效果系统的解耦通信机制，为后续效果处理和UI反馈奠定了基础。

目标:我们要实现的就是绑定委托，在给自身添加GE时，打印GE附加的Asset Tag

1.在效果中,添加此效果拥有的资产标签:

2.在Plugins/Runtime/GameplayAbilities/Source/GameplayAbilities/Public/AbilitySystemComponent.h

中:有相应的委托代码

cpp 复制代码

	/** Delegate for when an effect is applied */
	DECLARE_MULTICAST_DELEGATE_ThreeParams(FOnGameplayEffectAppliedDelegate, UAbilitySystemComponent*, const FGameplayEffectSpec&, FActiveGameplayEffectHandle);

这段代码是Unreal Engine中的多播委托声明，用于游戏效果应用时的事件通知。以下是关键点解析：

委托类型：DECLARE_MULTICAST_DELEGATE_ThreeParams声明了一个可绑定多个回调函数的多播委托
参数结构：委托接收三个参数：
- UAbilitySystemComponent*：指向能力系统组件的指针
- const FGameplayEffectSpec&：游戏效果规格的常量引用
- FActiveGameplayEffectHandle：活动游戏效果的句柄
典型用途：常用于游戏技能系统，当效果被施加到目标时触发相关事件
观察者模式：允许多个对象订阅此事件，实现解耦的事件通知机制

这种委托在UE的GameplayAbilitySystem中广泛使用，用于处理技能效果、状态变化等游戏逻辑的通信需求。

接着往下看，会发现基于这个委托宏，创建了多个委托属性，有添加GE给自身触发的，有添加给目标触发的，有持续时间的GE添加给自身触发的，还有周期性触发的GE的委托等等。

cpp 复制代码

/** Called on server whenever a GE is applied to self. This includes instant and duration based GEs. */
	FOnGameplayEffectAppliedDelegate OnGameplayEffectAppliedDelegateToSelf;

	/** Called on server whenever a GE is applied to someone else. This includes instant and duration based GEs. */
	FOnGameplayEffectAppliedDelegate OnGameplayEffectAppliedDelegateToTarget;

	/** Called on both client and server whenever a duration based GE is added (E.g., instant GEs do not trigger this). */
	FOnGameplayEffectAppliedDelegate OnActiveGameplayEffectAddedDelegateToSelf;

	/** Called on server whenever a periodic GE executes on self */
	FOnGameplayEffectAppliedDelegate OnPeriodicGameplayEffectExecuteDelegateOnSelf;

	/** Called on server whenever a periodic GE executes on target */
	FOnGameplayEffectAppliedDelegate OnPeriodicGameplayEffectExecuteDelegateOnTarget;

Unreal Engine GameplayEffect 委托技术文档

委托用途与区别

1. OnGameplayEffectAppliedDelegateToSelf

‌用途 ‌：当任意GameplayEffect(GE)被应用到自身时触发（服务器端）
‌特点‌：

包含瞬时效果和持续效果
仅在服务器端触发
适用于需要立即响应效果应用的逻辑

2. OnGameplayEffectAppliedDelegateToTarget

‌用途 ‌：当任意GameplayEffect被应用到其他目标时触发（服务器端）
‌特点‌：

包含瞬时效果和持续效果
仅在服务器端触发
适用于技能施放者监听目标效果

3. OnActiveGameplayEffectAddedDelegateToSelf

‌用途 ‌：当持续型GE被添加到自身时触发（客户端和服务器）
‌特点‌：

仅持续效果触发（瞬时效果不触发）
双端触发（客户端和服务器）
适用于需要同步显示的状态效果

4. OnPeriodicGameplayEffectExecuteDelegateOnSelf

‌用途 ‌：当周期性GE在自身执行时触发（服务器端）
‌特点‌：

仅周期性效果触发（如每2秒造成伤害）
仅在服务器端触发
适用于处理周期性伤害/治疗逻辑

5. OnPeriodicGameplayEffectExecuteDelegateOnTarget

‌用途 ‌：当周期性GE在目标执行时触发（服务器端）
‌特点‌：

仅周期性效果触发
仅在服务器端触发
适用于技能施放者监听目标的周期性效果

3.在Source/CC_Aura/Public/AbilitySystem/CC_AbilitySystemComponent.h

里面，添加一个多播委托:EffectApplied()

cpp 复制代码

protected:
	void EffectApplied(UAbilitySystemComponent* AbilitySystemComponent, const FGameplayEffectSpec& EffectSpec, FActiveGameplayEffectHandle ActiveEffectHandle);

(2)将EffectApplied()绑定到

cpp 复制代码

	/** Called on server whenever a GE is applied to self. This includes instant and duration based GEs. */
	FOnGameplayEffectAppliedDelegate OnGameplayEffectAppliedDelegateToSelf;

(3)创建一个函数,当我们初始化了能力信息时,绑定它:

cpp 复制代码

public:
	void AbilityActorInfoSet();

(4)在演员能力信息初始化时,调用:

cpp 复制代码

private:
	//初始化能力演员信息
	void InitCharacterAbilityInfo();

在Source/CC_Aura/Public/Characters/CC_CharacterBase.h

cpp 复制代码

protected:
	//初始化能力演员信息
	virtual void InitCharacterASC();

Source/CC_Aura/Public/Characters/CC_HeroCharacter.h:

cpp 复制代码

protected:
	//初始化能力演员信息
	virtual void InitCharacterASC() override;

Source/CC_Aura/Public/Characters/CC_EnemyCharacter.h:

cpp 复制代码

protected:
	//初始化能力演员信息
	virtual void InitCharacterASC() override;

cpp 复制代码

void ACC_EnemyCharacter::BeginPlay()
{
	Super::BeginPlay();
	InitCharacterASC();
}

void ACC_EnemyCharacter::InitCharacterASC()
{	// 为敌人类初始化演员能力信息
	AbilitySystemComponent->InitAbilityActorInfo(this,this);
	Cast<UCC_AbilitySystemComponent>(AbilitySystemComponent)->AbilityActorInfoSet();
}

(5)Source/CC_Aura/Private/AbilitySystem/CC_AbilitySystemComponent.cpp

效果:

源码:

Source/CC_Aura/Public/AbilitySystem/CC_AbilitySystemComponent.h

cpp 复制代码

// 版权归陈超所有

#pragma once

#include "CoreMinimal.h"
#include "AbilitySystemComponent.h"
#include "CC_AbilitySystemComponent.generated.h"

/**
 * 
 */
UCLASS()
class CC_AURA_API UCC_AbilitySystemComponent : public UAbilitySystemComponent
{
	GENERATED_BODY()
public:
	void AbilityActorInfoSet();
	
protected:
	void EffectApplied(UAbilitySystemComponent* AbilitySystemComponent, const FGameplayEffectSpec& EffectSpec, FActiveGameplayEffectHandle ActiveEffectHandle);
	
};

Source/CC_Aura/Private/AbilitySystem/CC_AbilitySystemComponent.cpp;

cpp 复制代码

// 版权归陈超所有


#include "AbilitySystem/CC_AbilitySystemComponent.h"

void UCC_AbilitySystemComponent::AbilityActorInfoSet()
{
	//多播委托,绑定回调函数
	OnGameplayEffectAppliedDelegateToSelf.AddUObject(this, &UCC_AbilitySystemComponent::EffectApplied);
}

void UCC_AbilitySystemComponent::EffectApplied(UAbilitySystemComponent* AbilitySystemComponent,
                                               const FGameplayEffectSpec& EffectSpec, FActiveGameplayEffectHandle ActiveEffectHandle)
{
	// GEngine->AddOnScreenDebugMessage(-1, 8.f, FColor::Blue, FString("Effect Applied!"));
	FGameplayTagContainer TagContainer;
	EffectSpec.GetAllAssetTags(TagContainer);
	for(const FGameplayTag& Tag : TagContainer)
	{
		//TODO: 将tag广播给Widget Controller
		const FString Msg = FString::Printf(TEXT("GE Tag: %s"), *Tag.ToString()); //获取Asset Tag
		GEngine->AddOnScreenDebugMessage(-1, 8.f, FColor::Cyan, Msg); //打印到屏幕上 -1 不会被覆盖
	}
}

Source/CC_Aura/Public/Characters/CC_CharacterBase.h:

cpp 复制代码

// 版权归陈超所有

#pragma once

#include "CoreMinimal.h"
#include "AbilitySystemInterface.h"
#include "GameFramework/Character.h"
#include "CC_CharacterBase.generated.h"


class UAbilitySystemComponent;
class UAttributeSet;
class USkeletalMeshComponent;

UCLASS(Abstract)
class CC_AURA_API ACC_CharacterBase : public ACharacter,public IAbilitySystemInterface
{
	GENERATED_BODY()

public:
	// 设置此角色属性的默认值
	ACC_CharacterBase();

	//重写接口函数，获取能力系统组件
	virtual UAbilitySystemComponent* GetAbilitySystemComponent() const override;

	//获取属性集
	virtual UAttributeSet* GetAttributeSet() const {return AttributeSet;};

protected:
	// 在游戏开始或生成时调用
	virtual void BeginPlay() override;

	UPROPERTY(EditAnywhere,Category="Combat")
	TObjectPtr<USkeletalMeshComponent> Weapon;

	UPROPERTY()
	TObjectPtr<UAbilitySystemComponent> AbilitySystemComponent;

	UPROPERTY()
	TObjectPtr<UAttributeSet> AttributeSet;

protected:
	//初始化能力演员信息
	virtual void InitCharacterASC();
};

Source/CC_Aura/Private/Characters/CC_CharacterBase.cpp:

cpp 复制代码

// 版权归陈超所有


#include "Characters/CC_CharacterBase.h"

#include "AbilitySystem/CC_AbilitySystemComponent.h"

// #include "AttributeSet.h"

// 设置默认值
ACC_CharacterBase::ACC_CharacterBase()
{
 	// 将此字符设置为每帧调用Tick（）。如果你不需要它，你可以关闭它来提高性能。
	PrimaryActorTick.bCanEverTick = false;

	//将武器添加到角色身上，并且武器跟随某个骨骼节点移动，形成手握武器效果。
	Weapon = CreateDefaultSubobject<USkeletalMeshComponent>(TEXT("Weapon"));	//创建默认子对象
	Weapon->SetupAttachment(GetMesh(), FName("WeaponHandSocket"));		//添加到父节点
	Weapon->SetCollisionEnabled(ECollisionEnabled::NoCollision);		//关闭骨骼网格体碰撞
	
}

//重写接口函数，获取能力系统组件
UAbilitySystemComponent* ACC_CharacterBase::GetAbilitySystemComponent() const
{
	return AbilitySystemComponent;
}

// 在游戏开始或生成时调用
void ACC_CharacterBase::BeginPlay()
{
	Super::BeginPlay();
	
}

void ACC_CharacterBase::InitCharacterASC()
{
}

Source/CC_Aura/Public/Characters/CC_HeroCharacter.h:

cpp 复制代码

// 版权归陈超所有

#pragma once

#include "CoreMinimal.h"
#include "Characters/CC_CharacterBase.h"
#include "CC_HeroCharacter.generated.h"

class UCameraComponent;
class USpringArmComponent;
/**
 * 
 */
UCLASS()
class CC_AURA_API ACC_HeroCharacter : public ACC_CharacterBase
{
	GENERATED_BODY()

public:
	//构造函数
	ACC_HeroCharacter();

	//服务器端初始化ASC
	virtual void PossessedBy(AController* NewController) override;;
	//客户端初始化ASC
	virtual void OnRep_PlayerState() override;
	
protected:
	//初始化能力演员信息
	virtual void InitCharacterASC() override;

#pragma region Components
	//弹簧臂组件
	UPROPERTY(VisibleAnywhere, BlueprintReadOnly, Category = "Camera", meta = (AllowPrivateAccess = "true"))
	TObjectPtr<USpringArmComponent> SpringArm;
	
	//跟随摄像机组件
	UPROPERTY(VisibleAnywhere, BlueprintReadOnly, Category = "Camera", meta = (AllowPrivateAccess = "true"))
	TObjectPtr<UCameraComponent> FollowCamera;
	
#pragma endregion
	
};

Source/CC_Aura/Private/Characters/CC_HeroCharacter.cpp:

cpp 复制代码

// 版权归陈超所有


#include "Characters/CC_HeroCharacter.h"

// #include "AbilitySystemComponent.h"
#include "AbilitySystem/CC_AbilitySystemComponent.h"
#include "Camera/CameraComponent.h"
#include "GameFramework/CharacterMovementComponent.h"
#include "GameFramework/SpringArmComponent.h"
#include "Player/CC_PlayerController.h"
#include "Player/CC_PlayerState.h"
#include "UI/HUD/CC_HUD.h"

ACC_HeroCharacter::ACC_HeroCharacter()
{
	//角色本身的设置（俯视角游戏）
	GetCharacterMovement()->bOrientRotationToMovement = true; //设置为true，角色将朝移动的方向旋转
	GetCharacterMovement()->RotationRate = FRotator(0.f, 400.f, 0.f); //旋转速率
	GetCharacterMovement()->bConstrainToPlane = true; //约束到平面
	GetCharacterMovement()->bSnapToPlaneAtStart = true; //设置了上面一项为true，且此项设置为true，则在开始时与地面对齐

	bUseControllerRotationPitch = false;	//同时需要确保角色本身不跟随控制器旋转：
	bUseControllerRotationYaw = false;
	bUseControllerRotationRoll = false;
	
	//弹簧臂组件
	SpringArm = CreateDefaultSubobject<USpringArmComponent>(TEXT("SpringArm"));
	SpringArm->SetupAttachment(RootComponent);	//设置附着点（跟组件）
	SpringArm->TargetArmLength = 900;
	SpringArm->SetRelativeRotation(FRotator(-45.f, 0, 0));	//设置相对旋转 设置俯视角度（Pitch负值）
	SpringArm->bUsePawnControlRotation = false;	//确保不随角色转向而转动
	SpringArm->bInheritPitch = false;	//取消继承俯仰
	SpringArm->bInheritRoll = false;	//取消继承翻滚
	SpringArm->bInheritYaw = false;		//取消继承摇摆
	SpringArm->bEnableCameraLag = true;	//相机延迟效果
		
	//跟随摄像机组件
	FollowCamera = CreateDefaultSubobject<UCameraComponent>(TEXT("FollowCamera"));
	FollowCamera->SetupAttachment(SpringArm, USpringArmComponent::SocketName); //设置附着点（弹簧臂组件接口名称）
	FollowCamera->bUsePawnControlRotation = false;
	

	
}

void ACC_HeroCharacter::PossessedBy(AController* NewController)
{
	Super::PossessedBy(NewController);
	//服务器端初始化ASC
	InitCharacterASC();
}

void ACC_HeroCharacter::OnRep_PlayerState()
{
	Super::OnRep_PlayerState();
	//客户端初始化ASC
	InitCharacterASC();
}

void ACC_HeroCharacter::InitCharacterASC()
{
	ACC_PlayerState* CCPlayerState = GetPlayerState<ACC_PlayerState>();	//获取玩家状态
	// check(CCPlayerState);
	if (CCPlayerState == nullptr)
	{
		UE_LOG(LogTemp, Warning, TEXT("CCPlayerState: %s - CCPlayerState is nullptl"), *GetName());
		return;
	}
	//获取玩家角色的ASC、AS
	if (AbilitySystemComponent == nullptr || AttributeSet == nullptr)
	{
		AbilitySystemComponent = CCPlayerState->GetAbilitySystemComponent();
		AttributeSet = CCPlayerState->GetAttributeSet();
	}
	//初始化ASC
	AbilitySystemComponent->InitAbilityActorInfo(CCPlayerState, this);
	Cast<UCC_AbilitySystemComponent>(AbilitySystemComponent)->AbilityActorInfoSet();
	//获取玩家控制器
	ACC_PlayerController* CCPlayerController = Cast<ACC_PlayerController>(GetController());
	/*服务器中，拥有所有玩家控制器
	 * 客户端只拥有自己的玩家控制器,当控制器为空是，游戏不能崩溃
	 */
	if (CCPlayerController)
	{
		//获取HUD
		ACC_HUD* CCHUD = Cast<ACC_HUD>(CCPlayerController->GetHUD());
		if (CCHUD) //仅对本地控制的玩家有效
		{
			//初始化HUD
			CCHUD ->InitOverlay(CCPlayerController, CCPlayerState, AbilitySystemComponent, AttributeSet);
		}
	}
}

Source/CC_Aura/Public/Characters/CC_EnemyCharacter.h:

cpp 复制代码

// 版权归陈超所有

#pragma once

#include "CoreMinimal.h"
#include "Characters/CC_CharacterBase.h"
#include "Interations/CC_EnemyInterface.h"
#include "CC_EnemyCharacter.generated.h"

/**
 * 
 */
UCLASS()
class CC_AURA_API ACC_EnemyCharacter : public ACC_CharacterBase ,public ICC_EnemyInterface
{
	GENERATED_BODY()

public:
	ACC_EnemyCharacter();

	// ~Begin IEnemyInterface重写函数
	virtual void HighlightActor() override;
	virtual void UnHighlightActor() override;
	// ~End IEnemyInterface重写函数

protected:
	virtual void BeginPlay() override;

protected:
	//初始化能力演员信息
	virtual void InitCharacterASC() override;
};

Source/CC_Aura/Private/Characters/CC_EnemyCharacter.cpp:

cpp 复制代码

// 版权归陈超所有


#include "Characters/CC_EnemyCharacter.h"

#include "AbilitySystem/CC_AbilitySystemComponent.h"
#include "AbilitySystem/CC_AttributeSet.h"
#include "CC_Aura/CC_Aura.h"

//构造函数
ACC_EnemyCharacter::ACC_EnemyCharacter()
{
	//为网格设置碰撞响应
	GetMesh()->SetCollisionResponseToChannel(ECC_Visibility, ECR_Block);	//自定义碰撞，块碰撞

	//添加能力系统组件
	AbilitySystemComponent = CreateDefaultSubobject<UCC_AbilitySystemComponent>("AbilitySystemComponent");
	AbilitySystemComponent->SetIsReplicated(true); //设置组件用于在网络上复制
	AbilitySystemComponent->SetReplicationMode(EGameplayEffectReplicationMode::Minimal);	//复制模式

	//添加属性集
	AttributeSet = CreateDefaultSubobject<UCC_AttributeSet>("AttributeSet");
}

void ACC_EnemyCharacter::BeginPlay()
{
	Super::BeginPlay();
	InitCharacterASC();
}

void ACC_EnemyCharacter::InitCharacterASC()
{	// 为敌人类初始化演员能力信息
	AbilitySystemComponent->InitAbilityActorInfo(this,this);
	Cast<UCC_AbilitySystemComponent>(AbilitySystemComponent)->AbilityActorInfoSet();
}

//高亮显示角色
void ACC_EnemyCharacter::HighlightActor()
{
	GetMesh()->SetRenderCustomDepth(true);	//是否渲染自定义深度
	GetMesh()->SetCustomDepthStencilValue(CUSTOM_DEPTH_RED);		//自定义深度模板值

	Weapon->SetRenderCustomDepth(true);
	Weapon->SetCustomDepthStencilValue(CUSTOM_DEPTH_RED);
}

//取消高亮显示角色
void ACC_EnemyCharacter::UnHighlightActor()
{
	GetMesh()->SetRenderCustomDepth(false);
	Weapon->SetRenderCustomDepth(false);
}