UE4C++写一个开门事件

好的，以下是一个简单的UE4 C++代码示例，用于触发门的开启事件：

首先，创建一个继承自Actor的蓝图类，将门模型拖放到该类中，并为门添加一个Box组件作为门的触发器。

在.h文件中添加以下代码：

#pragma once

#include "CoreMinimal.h"
#include "GameFramework/Actor.h"
#include "MyDoor.generated.h"

UCLASS()
class MYPROJECT_API AMyDoor : public AActor
{
    GENERATED_BODY()

public:
    AMyDoor();

protected:
    UPROPERTY(VisibleAnywhere, Category = "Components")
    class UStaticMeshComponent* DoorMesh;

    UPROPERTY(VisibleAnywhere, Category = "Components")
    class UBoxComponent* TriggerBox;

    UPROPERTY(EditAnywhere, Category = "Properties")
    float OpenAngle = 90.0f;

    UPROPERTY(EditAnywhere, Category = "Properties")
    float DoorCloseDelay = 2.0f;

    float LastDoorOpenTime;

    UPROPERTY(EditAnywhere, Category = "Properties")
    float DoorOpenSpeed = 0.8f;

    UPROPERTY(EditAnywhere, Category = "Properties")
    float DoorCloseSpeed = 2.0f;

    UFUNCTION()
    void OnDoorOverlapBegin(class AActor* OverlappedActor, class AActor* OtherActor);

    UFUNCTION()
    void OnDoorOverlapEnd(class AActor* OverlappedActor, class AActor* OtherActor);

public:
    virtual void Tick(float DeltaTime) override;

};

在.cpp文件中添加以下代码：

#include "MyDoor.h"
#include "Components/StaticMeshComponent.h"
#include "Components/BoxComponent.h"

AMyDoor::AMyDoor()
{
    PrimaryActorTick.bCanEverTick = true;

    DoorMesh = CreateDefaultSubobject<UStaticMeshComponent>(TEXT("DoorMesh"));
    RootComponent = DoorMesh;

    TriggerBox = CreateDefaultSubobject<UBoxComponent>(TEXT("TriggerBox"));
    TriggerBox->SetupAttachment(RootComponent);

    TriggerBox->OnComponentBeginOverlap.AddDynamic(this, &AMyDoor::OnDoorOverlapBegin);
    TriggerBox->OnComponentEndOverlap.AddDynamic(this, &AMyDoor::OnDoorOverlapEnd);

    LastDoorOpenTime = 0.0f;
}

void AMyDoor::Tick(float DeltaTime)
{
    Super::Tick(DeltaTime);

    if (GetWorld()->TimeSeconds - LastDoorOpenTime > DoorCloseDelay)
    {
        float CurrentYaw = DoorMesh->GetComponentRotation().Yaw;
        float TargetYaw;

        if (CurrentYaw > 0)
        {
            TargetYaw = 0.0f;
        }
        else
        {
            TargetYaw = OpenAngle;
        }

        float NewYaw = FMath::FInterpTo(CurrentYaw, TargetYaw, DeltaTime, DoorCloseSpeed);
        DoorMesh->SetRelativeRotation(FRotator(0.0f, NewYaw, 0.0f));
    }
}

void AMyDoor::OnDoorOverlapBegin(class AActor* OverlappedActor, class AActor* OtherActor)
{
    if (OtherActor && OtherActor != this)
    {
        LastDoorOpenTime = GetWorld()->TimeSeconds;
        float CurrentYaw = DoorMesh->GetComponentRotation().Yaw;
        float NewYaw = FMath::FInterpTo(CurrentYaw, OpenAngle, GetWorld()->DeltaTimeSeconds, DoorOpenSpeed);
        DoorMesh->SetRelativeRotation(FRotator(0.0f, NewYaw, 0.0f));
    }
}

void AMyDoor::OnDoorOverlapEnd(class AActor* OverlappedActor, class AActor* OtherActor)
{
    if (OtherActor && OtherActor != this)
    {
        LastDoorOpenTime = GetWorld()->TimeSeconds;
    }
}

这个代码示例中，我们添加了一个门模型和一个Box组件用作门的触发器。在Box组件上注册了OnComponentBeginOverlap和OnComponentEndOverlap事件，当有物体进入或离开Box时，将触发相应的事件。在OnDoorOverlapBegin事件中，我们通过插值将门旋转到开启的角度，并在LastDoorOpenTime中存储当前时间。在Tick函数中，我们检查LastDoorOpenTime是否超过DoorCloseDelay，如果是，则插值将门旋转回关闭的角度。

最后，将蓝图类添加到场景中，运行游戏并测试门的开启和关闭事件。