Problems when streaming AR content using Unreal Engine 5.0.1

Gaming and Visualization Technologies XR – VR/AR/MR CloudXR (VR and AR Streaming)
1

I want to use UE5 to render a car model we have been working on, and then use the CloudXR SDK to stream that car as an AR object that can be placed in the scene using the CloudXR AR sample APK on android. I have managed to get it to work but I am facing some problems:

  1. The Car is rendered semi-transparent, as if it has low alpha values, some parts of the car are more transparent than others, windows for examples are so transparent they seem as if they aren’t rendered at all.
  2. I have used an empty scene with a camera as my default player character in UE5, when I place the car in the real world scene, the car isn’t pivoted to a fixed point in the scene, meaning it moves as I move my phone, so I can’t for example rotate around it to see how it looks from behind.

I have also tried streaming using Blender, didn’t face the pivot problem and was able to pivot the object to a fixed place, but the transparency problem was still present.
I have seen many other threads having the same transparency problem, but couldn’t come to a definitive reason or even a fix for this problem, so any help will be appreciated.

2

This has been a known and persistent problem for a year,
And it’s related to the fact that, instead of a normal alpha channel, there seems to be a grayscale based on the brightness of the scene.
Someone seems to have solved it with a workaround applied to each texure, indicating an alpha value greater than 1.

Nvidia reported that it has solved the problem, but the problem seems to persist for us too.

3

I haven’t tried that solution yet, but if you could guide me on how to achieve that result I would be really thankful. I don’t have much experience when it comes to textures and if this workaround should be done from inside the engine or somewhere else. At least until Nvidia solves the problem from their side.

4

Hi Amir
it’s not clear for me too,
thi is the response from one of the forum user
For now we’ve worked around the problem by applying a 1.1 scalefactor to the alpha values in the pixel shader (in the blitter).

5

Was there a solve to this? or could someone explain what this means to do?
For now we’ve worked around the problem by applying a 1.1 scalefactor to the alpha values in the pixel shader (in the blitter).
i set the opacity of a material to 1.5 but that did not help. Not sure if that is what the above is saying to do or not
I am having the same issues in 5.1