omni.kit.collaboration.presence_layer
######################################

Live Session: Presence Layer

Introduction
============
Presence Layer works for storage for exchanging persistent data for all users in the same Live Session. The theory
behind uses .live layer as transport layer, on top of which all user data are structured as USD prim. It provides
easy API to access the data without using raw USD API, and also event stream to subscribe the data changes. Currently,
it's used for spatial awareness, which includes the following applications:

* Bound Camera.
* Selections.
* User Following.

User can exchange and synchronize their local states of the above applications into the Presence Layer for other users
to be aware of.

Presence Layer is bound to UsdContext. For each context, it has an unique presence layer.