[UE4]使用UE4C++制作黑洞

新手学习UE4C++编程，在Udemy上学习的教程，第一个挑战任务，制作一个黑洞，以下为解答：
照着做的，不是所有代码都能看明白，请多指教

1. 创建一个Actor
2. 为Actor创建根组件MeshComp
3. 创建外圆为Actor提供Overlap事件判断吸入范围
4. 创建内圆为Actor提供Overlap事件判断是否销毁吸入的对象
5. 为内圆创建重叠事件

FPSBlackHole.h

// Fill out your copyright notice in the Description page of Project Settings.

#pragma once

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

class UStaticMeshComponent;
class USphereComponent;
UCLASS()
class FPSGAME_API AFPSBlackHole : public AActor
{
	GENERATED_BODY()
	
public:	
	// Sets default values for this actor's properties
	AFPSBlackHole();

protected:
	// Called when the game starts or when spawned
	virtual void BeginPlay() override;


	//创建网格体
	UPROPERTY(VisibleAnywhere, Category = "Components")
		UStaticMeshComponent* MeshComp;

	//创建内圆
	UPROPERTY(VisibleAnywhere, Category = "Components")
		USphereComponent* InnerSphereComponent;

	//创建外圆
	UPROPERTY(VisibleAnywhere, Category = "Components")
		USphereComponent* OuterSphereComponent;

	//重叠事件
	UFUNCTION()
		void OverlapInnerSphere(UPrimitiveComponent* OverlappedComponent, AActor* OtherActor, UPrimitiveComponent *OtherComp, int32 OtherBodyIndex, bool bFromSweep, const FHitResult& SweepResult);

public:	
	// Called every frame
	virtual void Tick(float DeltaTime) override;

	
	
};

FPSBlackHole.cpp

// Fill out your copyright notice in the Description page of Project Settings.

#include "FPSBlackHole.h"
#include "Components/SphereComponent.h"
#include "Components/StaticMeshComponent.h"
// Sets default values
AFPSBlackHole::AFPSBlackHole()
{
 	// 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;

	MeshComp = CreateDefaultSubobject<UStaticMeshComponent>(TEXT("MeshComp"));//创建
	MeshComp->SetCollisionEnabled(ECollisionEnabled::NoCollision);//去除碰撞
	RootComponent = MeshComp;//设为根组件

	InnerSphereComponent = CreateDefaultSubobject<USphereComponent>(TEXT("InnerSphereComponent"));//创建
	InnerSphereComponent->SetSphereRadius(100);//设置半径100
	InnerSphereComponent->SetupAttachment(MeshComp);//绑定到Meshcomp

	InnerSphereComponent->OnComponentBeginOverlap.AddDynamic(this, &AFPSBlackHole::OverlapInnerSphere);

	OuterSphereComponent = CreateDefaultSubobject<USphereComponent>(TEXT("OuterSphereComp"));//创建外圆
	OuterSphereComponent->SetSphereRadius(3000);//设置半径
	OuterSphereComponent->SetupAttachment(MeshComp);//附加到MeshComp

}

// Called when the game starts or when spawned
void AFPSBlackHole::BeginPlay()
{
	Super::BeginPlay();
	
}

void AFPSBlackHole::OverlapInnerSphere(UPrimitiveComponent* OverlappedComponent, AActor* OtherActor, UPrimitiveComponent *OtherComp, int32 OtherBodyIndex, bool bFromSweep, const FHitResult& SweepResult)
{
	if (OtherActor)
	{
		OtherActor->Destroy();
	}
}

// Called every frame
void AFPSBlackHole::Tick(float DeltaTime)
{
	Super::Tick(DeltaTime);


	TArray<UPrimitiveComponent*>OverlappingComps;
	OuterSphereComponent->GetOverlappingComponents(OverlappingComps);

	for (int32 i=0;i<OverlappingComps.Num();i++)
	{
		UPrimitiveComponent* PrimComp = OverlappingComps[i];
		if (PrimComp&&PrimComp->IsSimulatingPhysics())
		{
			const float SphereRadius = OuterSphereComponent->GetScaledSphereRadius();
			const float ForceStrength = -2000;

			PrimComp->AddRadialForce(GetActorLocation(), SphereRadius, ForceStrength, ERadialImpulseFalloff::RIF_Constant, true);
		}
	}

}