Unreal lose tracking of VR headset after running an external VR exe application

Hi,

I created a VR experience in Unreal, and inside the VR world, there is a button which can open an external exe, which is also a VR experence. It’s like a VR menu room (Unreal application) and a mini VR game (not created by Unreal and is an external exe). When you play the mini game, Unreal VR menu is still open at the back.

I tried different ways to open external exe, such as:

FPlatformProcess::CreateProc

FMonitoredProcess

FInteractiveProcess

They can all successfully launch external exe, but the problem is, when the external exe is done playing and closed, the Unreal VR menu application will lose vision tracking of Oculus. This problem only happens if the external exe is a VR application. I tried to launch a regular exe, such as browser, and there is no lose tracking problem when I “alt tab” to jump back to Unreal VR application.

This is what I got from output log:

LogHMD: Vision Tracking Acquired

LogHMD: Lost Vision Tracking

Is this a bug of Unreal? Is there any way which can let Oculus retracked by Unreal after running an external VR exe?

Many thanks!:slight_smile: