UE4 C++：事件绑定（输入、碰撞检测、定时器）

 目录

Input输入事件绑定

轴映射与动作映射：SetupPlayerInputComponent

编辑器设置对应名称、代码设置响应事件，实现具体动作

C++设置添加轴和动作映射

碰撞检测事件绑定

碰撞对象通道与预设

碰撞响应设置：是否模拟物理碰撞以及触发Overlap事件

碰撞响应类型：Blokc、Overlap、Ignore

C++实现

定时器Timer与事件绑定

设置定时器：SetTimer

清空定时器：ClearTimer

暂停和恢复：PauseTimer和UnPauseTimer

判断是否活跃且未暂停：IsTimerActive

获取定时器速率：GetTImerRate

获取经过时间和剩余时间：GetTimerElapsed & GetTimerRemaining

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虚幻引擎中的碰撞响应参考 | 虚幻引擎5.0文档 (unrealengine.com)

变量、定时器和事件 | 虚幻引擎5.0文档 (unrealengine.com) 

 虚幻引擎中的Gameplay定时器 | 虚幻引擎5.0文档 (unrealengine.com)

Input输入事件绑定

轴映射与动作映射：SetupPlayerInputComponent

编辑器设置对应名称、代码设置响应事件，实现具体动作

绑定名称及事件，Action还需绑定按键 

void AMyCharacter::SetupPlayerInputComponent(UInputComponent* PlayerInputComponent)
{
	Super::SetupPlayerInputComponent(PlayerInputComponent);
 
	PlayerInputComponent->BindAction("DropItem", EInputEvent::IE_Pressed, this, &AMyCharacter::DropItem);
	PlayerInputComponent->BindAction("Jump", IE_Pressed, this, &AMyCharacter::Jump);
	PlayerInputComponent->BindAxis("MoveForward", this, &AMyCharacter::MoveForward);
	PlayerInputComponent->BindAxis("MoveRight", this, &AMyCharacter::MoveRight);
	PlayerInputComponent->BindAxis("PitchCamera", this, &AMyCharacter::PitchCamera);
	PlayerInputComponent->BindAxis("YawCamera", this, &AMyCharacter::YawCamera);
}

事件：

void AMyCharacter::MoveForward(float AxisValue)
{
	MovementInput.X = FMath::Clamp<float>(AxisValue, -1.f, 1.f);
}
 
void AMyCharacter::MoveRight(float AxisValue)
{
	MovementInput.Y = FMath::Clamp<float>(AxisValue, -1.f, 1.f);
}
 
void AMyCharacter::PitchCamera(float AxisValue)
{
	CameraInput.Y = AxisValue;
}
 
void AMyCharacter::YawCamera(float AxisValue)
{
	CameraInput.X = AxisValue;
}

设置按键，游戏暂停可以继续响应

InputComponent->BindAction("ESCEvent", IE_Pressed, this, &ASLAiPlayerController::ESCEvent).bExecuteWhenPaused=true;//游戏暂停可以执行

C++设置添加轴和动作映射

	//添加、绑定ActionKeyMapping轴映射 方法一
	FInputActionKeyMapping onFire("OnFire", EKeys::LeftMouseButton, 0, 0, 0, 0);
	UPlayerInput::AddEngineDefinedActionMapping(onFire);
	PlayerInputComponent->BindAction("OnFire", IE_Pressed, this, &AMyCharacter::OnFire);
 
	//添加、绑定ActionKeyMapping轴映射 方法二
	UPlayerInput::AddEngineDefinedActionMapping(FInputActionKeyMapping("Sprint",EKeys::LeftShift));
	PlayerInputComponent->BindAction("Sprint", IE_Pressed,this,&AMyCharacter::StartSprint);
	PlayerInputComponent->BindAction("Sprint", IE_Released,this,&AMyCharacter::StopSprint);
 
	//添加、绑定AxisMapping轴映射
	UPlayerInput::AddEngineDefinedAxisMapping(FInputAxisKeyMapping("Turn", EKeys::MouseX, 1.0f));
	PlayerInputComponent->BindAxis("Turn", this, &AMyCharacter::OnTurn);
 

碰撞检测事件绑定

碰撞对象通道与预设

• 默认提供碰撞对象类型，如WorldStatic、WorldDynamic等，允许用户自定义
• 默认提供碰撞预设，如NoCollision、BlockAll、OverlapAll。允许用户自定义

碰撞响应设置：是否模拟物理碰撞以及触发Overlap事件

碰撞响应类型：Blokc、Overlap、Ignore

C++实现

• 注意Overlap Begin/End 的函数参数
• 注意OnHit的函数参数
• 注意Generated Hit Event的函数名
• 绑定函数可以用AddDynamic，也可以用FScriptDelegate委托
• 部分设置可不写，蓝图使用时再手动设置
• 写法支持UShapeComponent及其派生类，如USphereComponent、UBoxComponent等

    UPROPERTY(EditAnywhere)
		USceneComponent* Root;
 
	UPROPERTY(EditAnywhere)
		UStaticMeshComponent* Cube;
 
	UFUNCTION()
		virtual void OnOverlapBegin(UPrimitiveComponent* OverlappedComponent, AActor* OtherActor, UPrimitiveComponent* OtherComp, int32 OtherBodyIndex, bool bFromSweep, const FHitResult& SweepResult);
 
	UFUNCTION()
		virtual void OnOverlapEnd(UPrimitiveComponent* OverlappedComponent, AActor* OtherActor, UPrimitiveComponent* OtherComp, int32 OtherBodyIndex, bool bFromSweep, const FHitResult& SweepResult);
 
	UFUNCTION()
		virtual void OnHit(UPrimitiveComponent* HitComponent, AActor* OtherActor, UPrimitiveComponent* OtherComp, FVector NormalImpulse, const FHitResult& Hit);

ACollisionActor::ACollisionActor()
{
 	// Set this actor to call Tick() every frame.  You can turn this off to improve performance if you don't need it.
	PrimaryActorTick.bCanEverTick = true;
 
	Root = CreateDefaultSubobject(TEXT("RootScene"));
	SetRootComponent(Root);
 
	Cube = CreateDefaultSubobject(TEXT("Cube"));
	Cube->SetupAttachment(Root);
	static ConstructorHelpers::FObjectFinder mesh(TEXT("StaticMesh'/Engine/BasicShapes/Cube.Cube'"));
	if (mesh.Succeeded())
	{
		Cube->SetStaticMesh(mesh.Object);
	}
 
	// 设置是否开启物理模拟
	Cube->SetSimulatePhysics(false);
 
	// 开启 Generated Hit Event
	Cube->SetNotifyRigidBodyCollision(true);
	
	// 开启CCD Continuous collision detection (CCD) 连续式碰撞检测
	Cube->BodyInstance.SetUseCCD(true);
	
	// 开启Generate Overlap Events
	Cube->SetGenerateOverlapEvents(true);
 
	// 设置碰撞预设
	Cube->SetCollisionProfileName(TEXT("OverlapAll"));
	//Cube->SetCollisionResponseToAllChannels(ECR_Overlap);
 
	// 设置碰撞响应设置
	Cube->SetCollisionEnabled(ECollisionEnabled::QueryAndPhysics);
 
	// 绑定函数
	Cube->OnComponentBeginOverlap.AddDynamic(this, &ACollisionActor::OnOverlapBegin);
 
	// 绑定函数 使用委托
	FScriptDelegate OverlapEndDelegate;
	OverlapEndDelegate.BindUFunction(this, TEXT("OnOverlapEnd"));
	Cube->OnComponentBeginOverlap.Add(OverlapEndDelegate);
	
	// 绑定碰撞函数
	Cube->OnComponentHit.AddDynamic(this, &ACollisionActor::OnHit);
}

void ACollisionActor::OnOverlapBegin(UPrimitiveComponent* OverlappedComponent, AActor* OtherActor, UPrimitiveComponent* OtherComp, int32 OtherBodyIndex, bool bFromSweep, const FHitResult& SweepResult)
{
	UE_LOG(LogTemp, Warning, TEXT("Overlap Begin"));
}
 
void ACollisionActor::OnOverlapEnd(UPrimitiveComponent* OverlappedComponent, AActor* OtherActor, UPrimitiveComponent* OtherComp, int32 OtherBodyIndex, bool bFromSweep, const FHitResult& SweepResult)
{
	UE_LOG(LogTemp, Warning, TEXT("Overlap End"));
}
 
void ACollisionActor::OnHit(UPrimitiveComponent* HitComponent, AActor* OtherActor, UPrimitiveComponent* OtherComp, FVector NormalImpulse, const FHitResult& Hit)
{
	UE_LOG(LogTemp, Warning, TEXT("Hit"));
	Destroy();
}

定时器Timer与事件绑定

• 定时执行操作，可执行一次，或循环执行直到手动终止
• 定时器在全局定时管理器（FTimerManager类型）中管理。全局定时器管理器存在于游戏实例对象上以及每个场景中
• 定时器需要绑定委托或函数、作为执行体。这些函数将填充FTimerHandle定时器句柄
• FTimerHandle支持暂停、恢复倒计时；查询或更改剩余时间；取消定时器
• 设置定时器的函数
  • SetTimer 定时执行
  • SetTimerForNextTick 下一帧执行
• 案例
  • 定时SpawnActor
  • 定时销毁
  • buff持续、如霸体、持续伤害

设置定时器：SetTimer

• 支持FTimerDelegate委托，可以扩展使用Lambda表达式，可以带参数

template<class UserClass>
void SetTimer
(
    FTimerHandle & InOutHandle,
    UserClass * InObj,
    typename FTimerDelegate::TUObjectMethodDelegate_Const< UserClass >::FMethodPtr InTimerMethod,
    float InRate,
    bool InbLoop,
    float InFirstDelay
)

FTimerHandle SpawnerHandle;
 
GetWorldTimerManager().SetTimer(SpawnerHandle, this, &AEnenmySpawner::SpawnEnemy, 5.0f, true);	
 
void AEnenmySpawner::SpawnEnemy()
{
	GEngine->AddOnScreenDebugMessage(-1, 1.0f, FColor::Red, "Spawn");
}

 

清空定时器：ClearTimer

• ClearAllTimerForObject：清空与特定对象关联的所有定时器

GetWorldTimerManager().ClearTimer(SpawnerHandle);
 
// 参数传入一个对象，本例以 this 举例
GetWorldTimerManagerr().ClearAllTimersForObject(this);

暂停和恢复：PauseTimer和UnPauseTimer

GetWorldTimerManager().PauseTimer(SpawnerHandle);
GetWorldTimerManager().UnPauseTimer(SpawnerHandle);
GetWorldTimerManager().IsTimerPaused(SpawnerHandle);

判断是否活跃且未暂停：IsTimerActive

GetWorldTimerManager().IsTimerActive(SpawnerHandle);

获取定时器速率：GetTImerRate

句柄若无效则返回-1

GetWorldTimerManager().GetTimerRate(SpawnerHandle);

获取经过时间和剩余时间：GetTimerElapsed & GetTimerRemaining

句柄若无效，返回-1

句柄若无效，返回-1

GetWorldTimerManager().GetTimerElapsed(SpawnerHandle);
GetWorldTimerManager().GetTimerRemaining(SpawnerHandle);