WebXR get XRSession or onExit event

Questions
1

Hey, im trying out webXR with ThreeJs. Currently Im creating the VRButton and can enter the vr world and everything works well. But what I dont find on the web is how to get the navigator or the XRSession.
And further on how to get events from XRSession. I need to know when the user exits VR.

this is my onClick function which gets fired when clicking on VRButton.

private onClick() {

      Globals.vrEnabled = !Globals.vrEnabled

      this.sceneSetup.renderer.setAnimationLoop(this.xrRenderLoop.bind(this))

      this.sceneSetup.xrSession = this.sceneSetup.renderer.xr.getSession() // getSession() return null

      // Results in: VR SESSION null true
      console.log('VR SESSION', this.sceneSetup.xrSession, this.sceneSetup.renderer.xr.isPresenting)

      // Error because XRSession is null
      this.sceneSetup.xrSession.addEventListener('end', ()=> {
  
          console.log('END OF SESSION - NO VR ANYMORE')
      
      })
}

Problem is that the XRSession returned from getSession() is always null. Why is that? How to get the XRSession properly

2

The session variable is only set after WebXRManager.setSesstion() was called. And this only happens if you start a XR session by activating the ENTER VR button.

Have you considered to register event listeners to the session start and end events like so?

renderer.xr.addEventListener( 'sessionstart', function ( event ) {

    //

} );

renderer.xr.addEventListener( 'sessionend', function ( event ) {

    //

} );
3

I have seen that before, but it gave me an Error:

Property ‘addEventListener’ does not exist on type ‘WebXRManager’.

Found a workaround for this:

let xr : any = this.renderer.xr

xr.addEventListener('sessionstart', this.onSessionStart.bind(this))

xr.addEventListener('sessionend', this.onSessionEnd.bind(this))

Probably happens because of missing typescript typings.

Thanks @Mugen87

4

Should be fixed with next release!

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