GfXDevice does not support asynchronous readback error in Shared AR & Plane Tracking guide

  • Issue category: ARDK Documentation / Networking
  • Device type & OS version: Android 12 / POCO X3 Pro
  • Host machine & OS version: Windows 10
  • Issue Environment : Unity Remote / Unity Mock / On Device
  • ARDK version: 2.0.0
  • Unity version: 2020.3.32f1

Hi there,

I’m having issues with the Shared AR Session & Plane Tracking.

I’m setting up the AR Session Manager’s and Network Session Manager’s Runtime Environment option to Mock as per this post in both the AR Session Manager and Network Session Manager.

I made sure the Use with AR Networking Session is checked in both manager.
When I run the app, I get a “This GfxDevice does not support asynchronous readback”.

As a note, the LowLevelNetworking Scene and the Basic guide are working fine on my phone.

What am I mising?

Thanks for your help.

Hello Hanaë,

Is this occurring within Unity or when built to device? One thing to check are the Graphics API Settings for Windows, specifically, that Vulkan has been removed. These can be found In Unity 2020.3 through:

  • Edit > Project Settings > Player
  • Other Settings > Rendering > un-check the box for Auto Graphics API for Windows to show the list of available Graphics API for Windows.
  • Remove Vulkan

Please let me know if this helps. If the issue persists, please copy/paste your console logs and any helpful screenshots in your response.

Hello Erik,

Thanks for the reply.

This error is showing in loop in the Android logcat when building and running on the Android device.

After checking, Vulkan is removed and I did uncheck the box.
This my settings:

Is there other options I should look into?


Thank you for the update. Are you able to provide a copy/paste of your Android logcat and console errors please? I’m reaching out for further assistance, though with the holidays, I do expect some delay. I appreciate your patience.

Hi Erik,
Here is the logcat (I had to attach a file because of the characters limit.).

The Gfx error goes on until I close the app.
logcat_unity_shatred.txt (26.5 KB)

I hope this helps.

Thank you for your help.

Thank you for providing the logcat file. Are you meaning to build for Linux, or is it included as part of your Unity installation? I see several calls to it in the logcat file. Though we just checked your Graphics API for Windows settings to remove Vulkan, there is also an Auto Graphics API for Linux box. Will you check to ensure Vulkan has been removed there as well? Unfortunately, with those options aside, we don’t officially support Linux, so I’m not able to suggest other work arounds at this time.

Hi Erik,
I’m building for Android on a Windows machine. Not sure why I get Linux calls. In the Player settings for PC, MAC&Linux, I deactivated the Auto Graphics for everything but I’m building and runnning on an Android device so it does not change anything. I still get the same error.

I’ve forwarded your request to engineering for further review. Thank you for your patience while a solution is sought.