Can you use ALXR with an VPN?

[comsyspro]

I want to use a VR headset remotely, so that the VR application is running on a GPU server. The VR headset (wired) is connected to a Laptop and a VPN is created to the remote GPU server.

• Is this possible with ALXR?
• Can you specify the remote IP in the alxr-client.exe because there is only a --localhost switch?
• Do you need to install alxr-client-uwp_x.x.x.x_x64_arm64.msixbundle for this? (besides I can't install the .msixbundle because it is not signed)

Thank you.

[comsyspro]

• Now I was able to remotly connect to a GPU server but I have to solve one more issue with audio. Can you say why I can't hear audio over ALXR (is this ALVR or ALXR related)? Or how could I recieve audio from a remote GPU server?

• The certificate for the alxr-client-uwp_x.x.x.x_x64_arm64.msixbundle is outdated and I had to create an own to sign the msixbundle. I build the UWP on Windows 10 and there is now another error. The UWP installer wants Windows Server 2022 build version 20348 and doesn't work on Windows 10. Is the UWP only for Windows Server 2022 or Windows 11?

[korejan]

@comsyspro hey, the desktop clients currently don't have audio support but you might able to do that another way like using vb-audio on the client end since it's typically used for the windows server side streaming, not something i've tried though

Do you need to use the uwp builds? if not you can use the *-win-x64.zip builds then you have some commandline options available, the uwp ones are limited (in terms of options) and mainly meant for hololens 2. If you still want to make a custom uwp build you'll need modify the line:

    call !VCVarsAllBat! !arch! uwp 10.0.20348.0 # version no. is the win sdk version, you change or just remove it

in alvr\openxr-client\alxr-client\uwp\cargo_build_uwp.bat

If you do switch to the zip builds, note that the default options are broken as it will run auto-graphics selection and typically pick the Vulkan graphics backend (Vulkan2 or Vulkan, it's OpenXR specific thing) with the d3d11va decoder, this combo currently doesn't render correctly, you can change it, either changing the grahpics backend to d3d12/11 or change the decoder to NVDEC / CUVID / CPU when using Vulkan(2), e.g.:

alxr-client.exe -g D3D12 # or D3D11
# or
alxr-client.exe -dNVDEC #or CUVID / CPU

[comsyspro]

Thank you very much.

From vb-audio I installed on the remote GPU server "Virtual Audio Cable" and "Voicemeter" and played with different settings but I can't get audio sound. So I found a github project "audio over ip" and with this I get sound with a small latency but the sound is not 100% in sync with the videostream. So it would definitly be better if you could add audio support so the snyc between video and audio are ok. Would it be difficult to add audio support to ALXR?

I don't need the uwp builds necessarily but at the beginning I had a few difficulties getting the headset to work through the VPN connection. I then found this note in the wiki: "You will need to forward ports in the VM for the server to establish a connection". I then thought that this image with the NAT configuration was only available in the UWP version and then wanted to try to get this version to work. As I said, UWP is a bit difficult to install and I haven't used it yet. Can you explain what this picture means and what do you mean by the word VM? Is it a router configuration?

https://github.com/korejan/ALVR/wiki/ALXR-Client#uwp-x64arm64--hololens-2-device--emulator

So when I remove this line call !VCVarsAllBat! !arch! uwp 10.0.20348.0 it will choose the version it can find?

I also found out by experimenting that only alxr-client.exe -d NVDEC gives an image. Without this option only a green image was displayed. I omit this option alxr-client.exe -g D3D12 and it is then selected as default auto. But can you explain what this alxr-client.exe -g parameter does, does it affect performance?

Please answer my questions as I would like to understand your project better and it is new to me.