Not picking up the object at point of reach

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#1

When I pick up an object, it is not being placed in front of the pawn according to what the reach is. Its being placed at the center of my pawn and messing up the controls, and changing the reach in my grabber.h file doesn’t do anything.

Any thoughts?

#2

Can I have a picture of what you mean + code?

#3

838×596 498 KB

Here is the code in .h


#include "Components/ActorComponent.h"
#include "Grabber.generated.h"


UCLASS( ClassGroup=(Custom), meta=(BlueprintSpawnableComponent) )
class MYPROJECT_API UGrabber : public UActorComponent
{
	GENERATED_BODY()

public:	
	// Sets default values for this component's properties
	UGrabber();

	// Called when the game starts
	virtual void BeginPlay() override;
	
	// Called every frame
	virtual void TickComponent( float DeltaTime, ELevelTick TickType, FActorComponentTickFunction* ThisTickFunction ) override;

private:
	// How far ahead of the player can we reach in cm
	float Reach = 150.f;

	UPhysicsHandleComponent* PhysicsHandle = nullptr;
	UInputComponent* InputComponent = nullptr;

	// Ray-cast and grab what's in reach
	void Grab();
	void Release();
	// Find attached physics handle component
	void FindPhysicsHandleComponent();
	void SetupInputComponent();

	// Return hit for first physics body in reach
	const FHitResult GetFirstPhysicsBodyInReach();

	// Returns current start of reach line
	FVector GetReachLineStart();

	// Returns current end of reach line
	FVector GetReachLineEnd();

};

Here is the code in .cpp

#include "MyProject.h"
#include "Grabber.h"

#define OUT



// Sets default values for this component's properties
UGrabber::UGrabber()
{
	// Set this component to be initialized when the game starts, and to be ticked every frame.  You can turn these features
	// off to improve performance if you don't need them.
	bWantsBeginPlay = true;
	PrimaryComponentTick.bCanEverTick = true;

	// ...
}


// Called when the game starts
void UGrabber::BeginPlay()
{
	Super::BeginPlay();
	FindPhysicsHandleComponent();
	SetupInputComponent();
}

// Called every frame
void UGrabber::TickComponent(float DeltaTime, ELevelTick TickType, FActorComponentTickFunction* ThisTickFunction)
{

	Super::TickComponent(DeltaTime, TickType, ThisTickFunction);


	// if the physics handle is attached
	if (PhysicsHandle->GrabbedComponent)
	{
		PhysicsHandle->SetTargetLocation(GetReachLineStart());

	}

}

/// Look for attached Physics Handle
void UGrabber::FindPhysicsHandleComponent()
{
	PhysicsHandle = GetOwner()->FindComponentByClass<UPhysicsHandleComponent>();
	if (PhysicsHandle == nullptr)
	{
		UE_LOG(LogTemp, Error, TEXT("%s missing physics handle component"), *GetOwner()->GetName())
	}
};

void UGrabber::SetupInputComponent()
{
	/// Look for attached Input Component (Only appears at runtime)
	InputComponent = GetOwner()->FindComponentByClass<UInputComponent>();
	if (InputComponent)
	{
		UE_LOG(LogTemp, Warning, TEXT("Input Component found"))
		InputComponent->BindAction("Grab", IE_Pressed, this, &UGrabber::Grab);
		InputComponent->BindAction("Grab", IE_Released, this, &UGrabber::Release);
	}
	else
	{
		UE_LOG(LogTemp, Error, TEXT("%s missing Input Component"), *GetOwner()->GetName())
	}

}

void UGrabber::Grab()
{
		/// LINE TRACE and see if we reach any actors with physics collision channel set
	auto HitResult = GetFirstPhysicsBodyInReach();
	auto ComponentToGrab = HitResult.GetComponent();
	auto ActorHit = HitResult.GetActor();
		
	/// If we hit something then grab a physics handle
	if (ActorHit)
	{

		PhysicsHandle->GrabComponent(
			ComponentToGrab,
			NAME_None, // no bones needed
			ComponentToGrab->GetOwner()->GetActorLocation(),
			true // allow rotation

		);
	}
}

void UGrabber::Release()
{
		//TODO release physics handle
		PhysicsHandle->ReleaseComponent();
}


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

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

	/// see what we hit
	AActor* ActorHit = HitResult.GetActor();

	if (ActorHit)
	{
		UE_LOG(LogTemp, Warning, TEXT("Line trace hit: %s"), *(ActorHit->GetName()))

	}

	return HitResult;
}

FVector UGrabber::GetReachLineStart()
{
	FVector PlayerViewPointLocation;
	FRotator PlayerViewPointRotation;

	GetWorld()->GetFirstPlayerController()->GetPlayerViewPoint
	(
		OUT PlayerViewPointLocation,
		OUT PlayerViewPointRotation
	);

	return PlayerViewPointLocation;
}


FVector UGrabber::GetReachLineEnd()
{

	FVector PlayerViewPointLocation;
	FRotator PlayerViewPointRotation;

	GetWorld()->GetFirstPlayerController()->GetPlayerViewPoint
	(
		OUT PlayerViewPointLocation,
		OUT PlayerViewPointRotation
	);

	return PlayerViewPointLocation + PlayerViewPointRotation.Vector() * Reach;
}
#4

WAIT! I solved it!

Set target location was set to GetReachLineStart() insted of GetReachLineEnd here:

void UGrabber::TickComponent(float DeltaTime, ELevelTick TickType, FActorComponentTickFunction* ThisTickFunction)
{

	Super::TickComponent(DeltaTime, TickType, ThisTickFunction);


	// if the physics handle is attached
	if (PhysicsHandle->GrabbedComponent)
	{
		PhysicsHandle->SetTargetLocation(GetReachLineStart());

	}

}

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