[游戏开发]UE5/C++ 基于GAS创建攻击伤害 5.4.1 技能伤害效果对象注册

创建MMOARPGGameplayAbilityType.h，包含两个结构体

#pragma once

#include "CoreMinimal.h"
#include "Abilities/GameplayAbilityTargetTypes.h"
#include "MMOARPGGameplayAbilityType.generated.h"
/**
 * 
 */
USTRUCT(BlueprintType)
struct FMMOARPGGameplayEffects
{
	GENERATED_BODY()
public:
	UPROPERTY(EditAnywhere, BlueprintReadOnly, Category = GameplayEffects)
	TArray<TSubclassOf<UGameplayEffect>> TargetEffectClasses;//GE技能效果容器
};

USTRUCT(BlueprintType)
struct FMMOARPGGameplayEffectSpec
{
	GENERATED_BODY()

public:
	UPROPERTY(EditAnywhere, BlueprintReadOnly, Category = GameplayEffects)
	FGameplayAbilityTargetDataHandle TargetHandleData;//目标Handle数据

	UPROPERTY(EditAnywhere, BlueprintReadOnly, Category = GameplayEffects)
	TArray<FGameplayEffectSpecHandle> TargetEffectSpecs;//技能效果实例Handle
};

打开MMOARPGGameplayAbility.h，创建在蓝图可配置的GE类

#include "MMOARPGGameplayAbilityType.h"

UPROPERTY(EditDefaultsOnly, BlueprintReadOnly, Category = GameplayEffects)
TMap<FGameplayTag, FMMOARPGGameplayEffects> EffectMap;

打开MMOARPGGameplayAbility.cpp，实现伤害事件接口，注册伤害效果

void UMMOARPGGameplayAbility::OnDamageGameplayEvent(FGameplayTag InGameplayTag, FGameplayEventData Payload)
{
	//通过标签找到技能效果
	if (FMMOARPGGameplayEffects* InEffect = EffectMap.Find(InGameplayTag))
	{
		FMMOARPGGameplayEffectSpec GameplayEffectSpec;
		{
			//注册TargetDataHandle
			FGameplayAbilityTargetData_ActorArray* NewTargetData_ActorArray = new FGameplayAbilityTargetData_ActorArray;//存放TargetData的结构体
			NewTargetData_ActorArray->TargetActorArray.Add(const_cast<AActor*>(Payload.Target));//TargetActorArray是结构体内的目标容器，将EventData数据中的目标添加到容器中，记得去Const
			GameplayEffectSpec.TargetHandleData.Add(NewTargetData_ActorArray);//然后将这个NewTargetData注册到TargetDataHandle里

			//注册EffectSpecHandle
			for (auto& Tmp : InEffect->TargetEffectClasses)
			{
				FGameplayEffectSpecHandle NewEffectSpecHandle;
				//MakeOutgoingSpec函数，参数(TSubclassOf<UGameplayEffect>，float Level,FGameplayEffectContextHandle)，返回EffectSpecHandle
				NewEffectSpecHandle = GetAbilitySystemComponentFromActorInfo()->MakeOutgoingSpec(Tmp, 1, MakeEffectContext(CurrentSpecHandle, CurrentActorInfo));
				if (NewEffectSpecHandle.IsValid())
				{
					//通过CurrentSpecHandle寻找技能对象AbilitySpec
					FGameplayAbilitySpec* AbilitySpec = GetAbilitySystemComponentFromActorInfo()->FindAbilitySpecFromHandle(CurrentSpecHandle);

					//应用技能标签至技能效果对象，
					ApplyAbilityTagsToGameplayEffectSpec(*NewEffectSpecHandle.Data.Get(), AbilitySpec);

					if (AbilitySpec)
					{
						//对标签长度的量级进行赋值
						NewEffectSpecHandle.Data->SetByCallerTagMagnitudes = AbilitySpec->SetByCallerTagMagnitudes;

						//将EffectSpecHandle添加到容器TargetEffectSpecs中，完成注册
						GameplayEffectSpec.TargetEffectSpecs.Add(NewEffectSpecHandle);
					}
				}
			}
		}

		for (auto& Tmp : GameplayEffectSpec.TargetEffectSpecs)
		{
			//执行技能效果到目标,返回技能效果Handle
			TArray<FActiveGameplayEffectHandle>ActiveGameplayEffectHandles = K2_ApplyGameplayEffectSpecToTarget(Tmp, GameplayEffectSpec.TargetHandleData);
		}
	}
}