Get List of Spatial Anchors in Current Room?

The key outcome is that none of the returned anchors should be out of the player's view. 

I am wondering how you all have done, or would do this? I can think of several methods, but none seem particularly reliable. As far as I know you cannot query a specific room via the API, it's done automatically based on user's prior scans. So that creates several obstacles 1. The user may have scanned multiple rooms in their house, and 2. even if they didn't, we have no reference such as a room ID we can save along with the anchors IDs (if I'm wrong please let me know - that would be great)

One idea involves only showing anchors within a certain distance from the player, while taking into account distance from walls somehow - in order to prevent any anchor on the opposite side from a wall from showing. But that's just an idea.  

Any ideas would be much appreciated.