Stereo VR Portal WIP: Source available

Development Platform & Builds XR Development
1

I’ve been working on a portal actor that renders correctly in VR.

https://youtube.com/watch?v=tDQfUyV_l3k](https://www.youtube.com/watch?v=tDQfUyV_l3k)

Portal actor source so far https://drive.google.com/open?id=0Bx…W5BaDEyRkZmaTA

Current major obstacle is getting it to look nice with the VR late update, so if anyone has ideas, I’m all ears.

Material.jpg
Material.jpg1920×1080 326 KB

2

looking for this for long time :smiley:

Thx i hope that u could release it

3

I think I got a working later update solution for it that doesn’t bastardize anything. I’ll do some testing and then give you the header assuming everything works out.

Its just slightly earlier in the stack than the FSceneView late updates (scene captures sit there), but should be pretty close.

Edit Here is a full header for a scene capture class with a basic positional update just prior to rendering.

I didn’t fully implement your example so you’ll have to insert your custom stuff and replace my debug position setting (I saw you had some offset components or something for your portals).

This is the latest I could find to update them without engine edits.



#pragma once
#include "Components/SceneCaptureComponent2D.h"
#include "Camera/PlayerCameraManager.h"
#include "Engine/Engine.h"
#include "CoreMinimal.h"
#include "IHeadMountedDisplay.h"

#include "VRSceneCaptureComponent2D.generated.h"


UCLASS(Blueprintable, meta = (BlueprintSpawnableComponent))
class UVRSceneCaptureComponent2D : public USceneCaptureComponent2D
{
    GENERATED_BODY()

public:

    // Toggles applying late HMD positional / rotational updates to the capture
    UPROPERTY(BlueprintReadWrite, EditAnywhere)
        bool bTrackLocalHMDOrCamera;

    // If is an HMD enabled capture, is this the left eye
    UPROPERTY(BlueprintReadWrite, EditAnywhere)
        bool bIsLeftEye;

    virtual void UpdateSceneCaptureContents(FSceneInterface* Scene) override
    {

        // Apply eye offset
        // Apply eye matrix
        // Apply late update

        if (bTrackLocalHMDOrCamera)
        {

            EStereoscopicPass StereoPass = bIsLeftEye ? EStereoscopicPass::eSSP_LEFT_EYE : eSSP_RIGHT_EYE;

            FQuat Orientation = FQuat::Identity;
            FVector Position = FVector::ZeroVector;

            if (GEngine->HMDDevice.IsValid() && GEngine->IsStereoscopic3D() && GEngine->HMDDevice->IsHeadTrackingAllowed() && GEngine->HMDDevice->HasValidTrackingPosition())
            {
                GEngine->HMDDevice->GetCurrentOrientationAndPosition(Orientation, Position);

                float WorldToMeters = GetWorld() ? GetWorld()->GetWorldSettings()->WorldToMeters : 100.0f;

                GEngine->StereoRenderingDevice->CalculateStereoViewOffset(StereoPass, Orientation.Rotator(), WorldToMeters /*1.0f?*/, Position);

                this->bUseCustomProjectionMatrix = true;

                float ActualFOV = 90.0f;
                if (GEngine->HMDDevice.IsValid())
                {
                    float HMDVerticalFOV, HMDHorizontalFOV;
                    GEngine->HMDDevice->GetFieldOfView(HMDHorizontalFOV, HMDVerticalFOV);
                    if (HMDHorizontalFOV > 0)
                    {
                        ActualFOV = HMDHorizontalFOV;
                    }
                }

                this->CustomProjectionMatrix = GEngine->HMDDevice.Get()->GetStereoProjectionMatrix(StereoPass, ActualFOV);
                this->CaptureStereoPass = StereoPass;
            }
            else
            {
                this->bUseCustomProjectionMatrix = false;
                this->CaptureStereoPass = EStereoscopicPass::eSSP_FULL;

                APlayerController* Player = GetWorld()->GetFirstPlayerController();
                if (Player != nullptr && Player->IsLocalController())
                {
                    if (Player->GetPawn())
                    {
                        for (UActorComponent* CamComponent : Player->GetPawn()->GetComponentsByClass(UCameraComponent::StaticClass()))
                        {
                            UCameraComponent * CameraComponent = Cast<UCameraComponent>(CamComponent);

                            if (CameraComponent != nullptr && CameraComponent->bIsActive)
                            {
                                FTransform trans = CameraComponent->GetRelativeTransform();

                                Orientation = trans.GetRotation();
                                Position = trans.GetTranslation();
                                break;
                            }
                        }
                    }
                }
            }

            this->SetRelativeLocationAndRotation(Position, Orientation);
        }
        else
        {
            this->bUseCustomProjectionMatrix = false;
            this->CaptureStereoPass = EStereoscopicPass::eSSP_FULL;
        }

        // This pulls from the GetComponentToWorld so setting just prior to it should have worked    
        Super::UpdateSceneCaptureContents(Scene);
    }

};
4

Sorry for necroing this post but did you manage to have something good with this ? I’m looking for a Portal for VR too

5

Even with Mordentral’s modification, it isn’t really satisfactory for me. There’s still a noticeable lag and the performance cost is super heavy, essentially rendering the scene 4 times instead of just 2. This might be a case we need to wait for hardware to catch up to the concept.