Custom Pawn crashes the editor

[OmniOwl]

@The Beej;600757

Yes you should make UPROPERTY on every pointer that you store as a member variable of a UObject, AActor or UStruct, because then UE4 can take care of whether it still points to a valid object.

The only place you need the input component is within SetupPlayerInputComponent itself, and UE4 gives it to you inside that function (the argument named InputComponent). Your entire input code should look like this:

//header
	virtual void SetupPlayerInputComponent(class UInputComponent* InputComponent) override;
//cpp
void ABuildingEscapePawn::SetupPlayerInputComponent(class UInputComponent* InputComponent)
{
	Super::SetupPlayerInputComponent(InputComponent);
	InputComponent->BindAction("Use", EInputEvent::IE_Pressed, this, &ABuildingEscapePawn::Use);
	InputComponent->BindAction("Grab", EInputEvent::IE_Pressed, this, &ABuildingEscapePawn::Grab);
	InputComponent->BindAction("Grab", EInputEvent::IE_Released, this, &ABuildingEscapePawn::ReleaseGrab);
}

You don’t need to store any UInputComponent* or manually find the input component unless you’re doing some advanced input stuff.

C++ doesn’t work at all like Java or C#, there’s a bunch of gotchas and behaviours that are different especially with regard to objects, references, and memory management, and you won’t go far without learning them. Basically everyone will tell you the way to learn UE4 C++ is to get a solid understanding of C++ by itself first, then learn how to use UE4’s custom version of C++. You should use recent official tutorials from Epic instead of this Udemy class because it looks like it’s teaching you bad design.

I thank you for your advise to go and look at C++ more in-depth but I just can’t keep going back to zero all the time. I need to see that I can actually use C++ at all and I feel like I am making baby steps here. I won’t make perfect C++ code from the get-go just like how I didn’t learn how to make perfect Java or C# code. It’s okay to fail, as long as I learn from it

Now my code is a bit different, but still not working 100 %.
I can now get into the game but no WASD or Mouse Movement registers. I assume this is because the Basic Movement Input variable is not checked? If that’s the case, would I have to write my own code to make basic movement?

#include "BuildingEscape.h"
#include "BuildingEscapePawn.h"
#include "UseComponent.h"


// Sets default values
ABuildingEscapePawn::ABuildingEscapePawn()
{
	// Set this pawn to call Tick() every frame.  You can turn this off to improve performance if you don't need it.
	PrimaryActorTick.bCanEverTick = true;
}

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

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

}

// Called to bind functionality to input
void ABuildingEscapePawn::SetupPlayerInputComponent(class UInputComponent* InputComponent)
{
	Super::SetupPlayerInputComponent(InputComponent);
	if (InputComponent)
	{
		InputComponent->BindAction("Use", EInputEvent::IE_Pressed, this, &ABuildingEscapePawn::Use);
		InputComponent->BindAction("Grab", EInputEvent::IE_Pressed, this, &ABuildingEscapePawn::Grab);
		InputComponent->BindAction("Grab", EInputEvent::IE_Released, this, &ABuildingEscapePawn::ReleaseGrab);
	}
	else
	{
		UE_LOG(LogTemp, Error, TEXT("%s missing input component"), *(GetController()->GetPawn()->GetName()));
	}
}

void ABuildingEscapePawn::Use()
{
	if (PhysicsHandle)
	{
		if (!PhysicsHandle->GrabbedComponent)
		{
			FHitResult HitResult = GetFirstUseHandleInReach();
			AActor* ActorHit = HitResult.GetActor();
			if (ActorHit)
			{
				UUseComponent* UseComp = ActorHit->FindComponentByClass<UUseComponent>();
				if (UseComp)
				{
					UseComp->FireUseEvent();
				}
			}
		}
	}
}

void ABuildingEscapePawn::Grab()
{
	/// Line trace and see if we reach any actors with physics body collision channel set
	FHitResult HitResult = GetFirstPhysicsBodyInReach();
	UPrimitiveComponent* ComponentToGrab = HitResult.GetComponent();
	AActor* ActorHit = HitResult.GetActor();

	/// If we hit something, then attach a physics handle
	if (ActorHit && PhysicsHandle)
	{
		PhysicsHandle->GrabComponent(ComponentToGrab, EName::NAME_None, ComponentToGrab->GetOwner()->GetActorLocation(), true); // true is to allow rotation
	}
}

void ABuildingEscapePawn::ReleaseGrab()
{
	PhysicsHandle->ReleaseComponent();
}

void ABuildingEscapePawn::FindPhysicsHandleComponent()
{

	PhysicsHandle = GetController()->GetPawn()->FindComponentByClass<UPhysicsHandleComponent>();
	if (PhysicsHandle == nullptr)
	{
		UE_LOG(LogTemp, Error, TEXT("%s missing physics handle component"), *(GetController()->GetPawn()->GetName()));
	}
}

const FHitResult ABuildingEscapePawn::GetFirstUseHandleInReach()
{
	/// Line-trace (AKA ray-cast) out to reach
	FHitResult HitResult;
	// Setup Query parameters
	FCollisionQueryParams TraceParameters(FName(TEXT("")), false, GetController()->GetOwner());
	GetWorld()->LineTraceSingleByChannel(HitResult, GetReachLineStart(), GetReachLineEnd(), ECollisionChannel::ECC_Visibility, TraceParameters);

	return HitResult;
}

const FHitResult ABuildingEscapePawn::GetFirstPhysicsBodyInReach()
{
	/// Line-trace (AKA ray-cast) out to reach 
	FHitResult HitResult;
	// Setup query parameters
	FCollisionQueryParams TraceParameters(FName(TEXT("")), false, GetController()->GetOwner());

	GetWorld()->LineTraceSingleByObjectType(OUT HitResult, GetReachLineStart(), GetReachLineEnd(), FCollisionObjectQueryParams(ECollisionChannel::ECC_PhysicsBody), TraceParameters);

	return HitResult;
}

FVector ABuildingEscapePawn::GetReachLineStart()
{
	FVector PlayerViewPointLocation;
	FRotator PlayerViewPointRotation;
	GetWorld()->GetFirstPlayerController()->GetPlayerViewPoint(OUT PlayerViewPointLocation, OUT PlayerViewPointRotation);

	return PlayerViewPointLocation;
}

FVector ABuildingEscapePawn::GetReachLineEnd()
{
	FVector PlayerViewPointLocation;
	FRotator PlayerViewPointRotation;
	GetWorld()->GetFirstPlayerController()->GetPlayerViewPoint(OUT PlayerViewPointLocation, OUT PlayerViewPointRotation);

	return PlayerViewPointLocation + (PlayerViewPointRotation.Vector() * Reach);
}