UE + VR Ramp-up

Setting Up basic scene:

---

Creating VRCharacter

Set Camera

// header:
private:
    //UPROPERTY(VisibleAnywhere)
    class UCameraComponent* Camera;

//class:
#include "Camera/CameraComponent.h"

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

	Camera = CreateDefaultSubobject<UCameraComponent>(TEXT("Camera"));
	Camera->SetupAttachment(GetRootComponent());
}

    Blueprints > GameMode: GameModeBase > Create > GameModeBase

    Change default pawn class to my character class

Set movement

//header:
private:

	void MoveForward(float throttle);
	void MoveRight(float throttle);

//class:
// Called to bind functionality to input
void AVRCharacter::SetupPlayerInputComponent(UInputComponent* PlayerInputComponent)
{
	Super::SetupPlayerInputComponent(PlayerInputComponent);

	PlayerInputComponent->BindAxis(TEXT("Forward"), this, &AVRCharacter::MoveForward);
	PlayerInputComponent->BindAxis(TEXT("Right"), this, &AVRCharacter::MoveRight);
}

void AVRCharacter::MoveForward(float throttle)
{
	AddMovementInput(throttle * Camera->GetForwardVector());
}

void AVRCharacter::MoveRight(float throttle)
{
	AddMovementInput(throttle * Camera->GetRightVector());
}

• Create axis mapping on UE interface.

    settings -> Project settings -> Engine/Input -> Create axis mapping*

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Proposed solution to attach character on camera

• There's a restriction basically with characters you cant move their capsules.

• Character must move acording the VR head, but because of the childing the player will move together.

  • To solve this: Move the VR root to opposite direction, so it will center character and Camera on desired location.
    
    

   
   VRRoot = CreateDefaultSubobject<USceneComponent>(TEXT("VRRoot"));
   VRRoot->SetupAttachment(GetRootComponent());
  
   Camera = CreateDefaultSubobject<UCameraComponent>(TEXT("Camera"));
   Camera->SetupAttachment(VRRoot);	//Camera attach VR root
  

---

Line tracing a teleportation

1. Find the teleport destination
2. Show the destination to the player
3. Fade out the viewport
4. Move the player to the destination
5. Fade back in

//In Editor create an primitive object attached on player (Use blueprints to it, apparently is required go very deep in UE classes hyerarch to create primitives in c++)


//header:
private:

	void UpdateDestinationMarker();

	UPROPERTY(VisibleAnywhere)
	class UStaticMeshComponent* DestinationMarker;

	UPROPERTY(VisibleAnywhere)
	float MaxTeleportDistance = 1000; //10 meters

//class:
//Calls on AVRCharacter attaching the destination marker position to Root Component (The BP_VRCharacter) :
	DestinationMarker = CreateDefaultSubobject<UStaticMeshComponent>(TEXT("DestinationMarker"));
	DestinationMarker->SetupAttachment(GetRootComponent());

void AVRCharacter::UpdateDestinationMarker()
{
	FVector Start = Camera->GetComponentLocation();
	FVector End = Start + Camera->GetForwardVector() * MaxTeleportDistance;

	FHitResult HitResult;
	bool bHit = GetWorld()->LineTraceSingleByChannel(HitResult, Start, End, ECC_Visibility);

	if (bHit) {
		DestinationMarker->SetWorldLocation(HitResult.Location);
	}
}



// Problem: If there's collision our primitive will be hit by the ray that is being projected to the worod.

// Solution: BP Editor -> DestinationMarker -> Details Panel -> Collision -> Collision Presets -> Set to NoCollision

Fading and Creating Timer

---

#include "Camera/PlayerCameraManager.h"
#include "TimerManager.h"
#include "Components/CapsuleComponent.h"

//Bind Action to user input:
PlayerInputComponent->BindAction(TEXT("StartFade"), IE_Released ,this, &AVRCharacter::FadeIn);


//Fade and timer logic:
void AVRCharacter::FadeIn()
{
	APlayerController* PC = Cast<APlayerController>(GetController());
	
	if (PC != nullptr) { 
		PC->PlayerCameraManager->StartCameraFade(0,1, FadeTime, FLinearColor::Black); 
	}
	
	FTimerHandle Handle;
	GetWorldTimerManager().SetTimer(Handle, this, &AVRCharacter::FadeOut, FadeTime, false);
}


void AVRCharacter::FadeOut()
{
	APlayerController* PC = Cast<APlayerController>(GetController());

	if (PC != nullptr) {
		PC->PlayerCameraManager->StartCameraFade(1, 0, FadeTime, FLinearColor::Black);
	}
}

NavMesh

Model  panel -> Nav Mesh Bounds Volume
Press P to show/hide 

In YourProjectNameBuild.cs, insert "NavigationSystem" Module in PublicDependencyModuleNames List:

		PublicDependencyModuleNames.AddRange(new string[] { "Core", "CoreUObject", "Engine", "InputCore", "NavigationSystem" });

---

//Adding navMesh reference

//Header:	
private:
	UPROPERTY(EditAnywhere)
	FVector TeleportProjectionExtent = FVector(100, 100, 100);

//File:

#include "NavigationSystem.h"

FNavLocation NavLocation;

//Returns true if is poiting to navMesh
UNavigationSystemV1::GetCurrent(GetWorld())->ProjectPointToNavigation(HitResult.Location, NavLocation, TeleportProjectionExtent);

Editing post processing material

https://prnt.sc/13bjmmb

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Unity to Unreal glossary

Unity	Unreal	API Reference
Mesh	UStaticMeshComponent	https://docs.unrealengine.com/en-US/API/Runtime/Engine/Components/UStaticMeshComponent/index.html
RayCast	UWorld::LineTraceSingleByChannel	https://docs.unrealengine.com/en-US/API/Runtime/Engine/Engine/UWorld/LineTraceSingleByChannel/index.html
Manipulating deltatime	FTimerManager::SetTimer	https://docs.unrealengine.com/en-US/API/Runtime/Engine/FTimerManager/SetTimer/index.html
Transform = new Vector3(Transform)	SetActorLocation(OtherComponent->GetComponentLocation());	https://docs.unrealengine.com/en-US/API/Runtime/Engine/GameFramework/AActor/SetActorLocation/index.html
Debug.Log("") print("")	UE_LOG(Category, Verbosity, (TEXT(""))	https://docs.unrealengine.com/en-US/ProgrammingAndScripting/ProgrammingWithCPP/UnrealArchitecture/StringHandling/index.html
OnTriggerXXXX(collider other)	TriggerVolume->IsOverlappingActor(ActorEvent)	https://docs.unrealengine.com/en-US/API/Runtime/Engine/GameFramework/AActor/IsOverlappingActor/index.html

//Raycst in code example:
bool LineTraceSingleByChannel
(
    struct FHitResult & OutHit, // Empty hit result
    const FVector & Start, // Pass a reference toi the memory but cant edit that memory. When we dont put const in memory type parameter we indicate that value mighty be changed
    const FVector & End,
    ECollisionChannel TraceChannel,
    const FCollisionQueryParams & Params,	//Optional
    const FCollisionResponseParams & ResponseParam //Optional
) const 

//TimeDeltaTime
FTimerHandle Handle;
GetWorldTimerManager().SetTimer(Handle, this, &ClientCall::FinishFade, FadeTime, false);

//Hello example
FString Log = TEXT("Hello");
FString* PrtLog = &Log;

Log.Len();

PrtLog->Len();

UE_LOG(LogTemp, Warning, TEXT("%s"), **PrtLog /* Derefencing and using overload operator */)

//Acces object name
*GetOwner()->GetName();

//Access object transform
GetOwner()->GetTransform()

//Rotation Sample

float InitialYaw;
float CurrentYaw;
float TargetYaw;

CurrentYaw = FMath::Lerp(CurrentYaw, TargetYaw, 0.02f);
FRotator Rotation = GetOwner()->GetActorRotation();
Rotation.Yaw = CurrentYaw;
GetOwner()->SetActorRotation(Rotation);	

//Collision Trigger

//h
#include "Engine/TriggerVolume.h"

UPROPERTY(EditAnywhere)
ATriggerVolume* TriggerPointer;

UPROPERTY(EditAnywhere)
AActor* ActorEvent;

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Tips

Multible triggers setup on Project Settings > Engine > Input

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• In Blank Scene notes:

  • PlayerController.AbsoluteRotation: Has VR rotation update.

  • PlayerController.location: does not update

  • PlayerCameraManager.Rotation: VR Update

  • PlayerCameraManager.location: update acording move input