OpenDoorWithLerp.cpp

// Harrison McGuire
// UE4 Version 4.20.2
// https://github.com/Harrison1/unrealcpp
// https://severallevels.io
// https://harrisonmcguire.com

// helpful links
// https://docs.unrealengine.com/latest/INT/API/Runtime/Engine/Components/USceneComponent/index.html
// https://docs.unrealengine.com/latest/INT/API/Runtime/Engine/Components/UPrimitiveComponent/OnComponentBeginOverlap/
// https://docs.unrealengine.com/latest/INT/API/Runtime/Engine/Components/UPrimitiveComponent/OnComponentEndOverlap/
// https://docs.unrealengine.com/latest/INT/BlueprintAPI/Math/Vector/UnrotateVector/
// https://docs.unrealengine.com/latest/INT/API/Runtime/Engine/Kismet/UKismetMathLibrary/LessLess_VectorRotator/index.html
// https://docs.unrealengine.com/latest/INT/API/Runtime/Engine/Kismet/UKismetMathLibrary/index.html

#include "OpenDoorWithLerp.h"
#include "Components/BoxComponent.h"
#include "Kismet/KismetMathLibrary.h"

// Sets default values
AOpenDoorWithLerp::AOpenDoorWithLerp()
{
 	// 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;

	Open = false;

    MyBoxComponent = CreateDefaultSubobject<UBoxComponent>(TEXT("My Box Component"));
    MyBoxComponent->InitBoxExtent(FVector(50,50,50));
    RootComponent = MyBoxComponent;

    Door = CreateDefaultSubobject<UStaticMeshComponent>(TEXT("My Mesh"));
    Door->SetRelativeLocation(FVector(0.0f, 50.0f, -50.0f));
    Door->SetupAttachment(RootComponent);

    MyBoxComponent->OnComponentBeginOverlap.AddDynamic(this, &AOpenDoorWithLerp::OnOverlapBegin);
    MyBoxComponent->OnComponentEndOverlap.AddDynamic(this, &AOpenDoorWithLerp::OnOverlapEnd);

}

// Called every frame
void AOpenDoorWithLerp::Tick(float DeltaTime)
{
	Super::Tick(DeltaTime);
	// maybe in UE5,RelativeRotation is private
	DoorRotation = Door->GetRelativeRotation();

    if(Open)
    {
        Door->SetRelativeRotation(FMath::Lerp(FQuat(DoorRotation), FQuat(FRotator(0.0f, RotateValue, 0.0f)), 0.01f));   
    } 
    else
    {
        Door->SetRelativeRotation(FMath::Lerp(FQuat(DoorRotation), FQuat(FRotator(0.0f, 0.0f, 0.0f)), 0.01f));
    }

}

void AOpenDoorWithLerp::OnOverlapBegin(class UPrimitiveComponent* OverlappedComp, class AActor* OtherActor, class UPrimitiveComponent* OtherComp, int32 OtherBodyIndex, bool bFromSweep, const FHitResult& SweepResult)
{
    if (OtherActor != nullptr && OtherActor != this && OtherComp != nullptr) 
    {
        FVector PawnLocation = OtherActor->GetActorLocation();
        FVector Direction = GetActorLocation() - PawnLocation;
        Direction = UKismetMathLibrary::LessLess_VectorRotator(Direction, GetActorRotation());

        if(Direction.X > 0.0f)
        {
            RotateValue = 90.0f;
        }
        else
        {
            RotateValue = -90.0f;
        }

        Open = true;
    }
}

void AOpenDoorWithLerp::OnOverlapEnd(class UPrimitiveComponent* OverlappedComp, class AActor* OtherActor, class UPrimitiveComponent* OtherComp, int32 OtherBodyIndex)
{
    if (OtherActor != nullptr && OtherActor != this && OtherComp != nullptr)  
    {
        Open = false;
    }
}