Scene Capture Cube in VR turns green

Development Platform & Builds XR Development
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1

I’m making a VR game on Meta Quest 2.
Therefore, it is absolutely necessary to use Scene Capture Cube.
And I want it to keep updating the scene while moving.
So we don’t consider making the capture result a static texture. I need to keep capturing 360 degree images in real time.
I know I’m not recommending it because it’s a heavy load, but I want to do it.

However, when checking with UE5.1 on the actual Quest2, all the captured objects are all green.

After trying various things, I found that the Scene Capture Cube turns green (or the image does not update) when the drawing preview is set to Android even on the editor.
SceneCaputure2D works fine.

This didn’t happen with UE4.27.2.

In other words, on mobile, Scene Capture Cube cannot be used with UE5.1.
Can this be fixed with settings?
Please help if anyone knows.

2

The reason I’m trying to do this is because I want to change the angle of view of the camera to 180 degrees or more in VR.

I place a hemispherical mesh in front of the VR character’s camera and capture the SceneCaputure results there. (SceneCaputure’s camera moves with the character)

In Quest2, the angle of view of the camera is fixed at 90 degrees. (The actual appearance does not change even if the FOV is changed.)

If you project the SceneCaputure2D result to the hemisphere, it will be reflected beautifully. Now you can change the angle of view of the camera from 0 to 180 degrees. (Although there are problems such as increased load and loss of stereoscopic effect, priority is given to changing the angle of view.)

Next, when you want to go over 180 degrees, you can’t do it with SceneCapture2D, so use SceneCaputureCube.
This can also be achieved by projecting the result on a hemisphere. (It was possible in UE4.27.2)

However, I have to develop with UE5.1 for some reason.
So it would be great if SceneCaputureCube could be rendered on mobile even in 5.1.

3

So if there is another way to change the angle of view of the Quest2’s camera, you don’t have to use this method.

If you know it please let me know. If there is no way to do that, how can I still get Cube to render successfully?

4

The field of view in VR is determined by the projection matrices returned for each eye from the VR plugin. To change the FoV, you would need recompile the engine, and modify the implementation of IStereoRendering::GetStereoProjectionMatrix() of the plugin you are using.

5

thank you.
Do you know the details of how to do that?

6

Assuming you are using the OpenXR plugin, you would have to edit FOpenXRHMD::GetStereoProjectionMatrix() in OpenXRHMD.cpp, and change the angles used to construct the matrices. Guessing it would still be limited to a maximum of 180 degrees though.

1 Like
7

By the way, the green phenomenon also occurred in UE5.1.1.

8

Hello! Have you found a solution with a green screen? I have a similar problem. UE 5.0.3. The mirrors in my VR scene are made using Screen Capture Cube. Everything works in Vr preview mode, but when I pack the scene, the mirrors in it are displayed in green. Do you have any ideas how to fix it?

9

Hi , Have you find any solution on Green Screen.

10

Hello. I also have the green issue in UE 5.3.2 when running a build on Meta Quest 2. @saito_y have you figured it out?