Resolved Portably retrieving reality up vector

Is there a portable way to retrieve [at least an estimate of] the real-world up or down vector (i.e. a direction parallel to gravity) when using the Unity XR plugin architecture?

It's possible this is a silly question, but most of the apps I've written don't care about world space (mostly I work in some arbitrary headset relative space defined by video + external tracking input) so I never really looked into it before.

 

ARFoundation is set up such that Vector3.up in worldspace corresponds with the real-world up-vector.

Edit: Of course, it also assumes that the earth is a flat plane So depending on how 'big' you application is, you might need to start looking at other ways to do this otherwise (e.g. by directly reading from the Accelerometer)

 

Perfect, thank you!