Greetings,
As I understand it, PlayerIO requires players to be separated into rooms, which can be considered a trivial form of ROI management. As long as there is no limitation on when players can be moved from room-to-room, this is sufficient for me to implement a sort of open world for a game like Aetheria where rooms could be connected by wormholes and loading screens.
Aetheria is currently on my backburner as I work on another game, Rust to Dust, the networking for which requires a rather more convincing open world implementation. With what PlayerIO provides by default, a naive grid-based implementation would result in not being able to see players right next to you when you are standing near the border of a grid cell. The best I could accomplish is "sharding" the world into stochastically sampled localized clusters of players not exceeding the room size limit, but that is both a lot of engineering and not likely to yield great results (what if you agree to meet somewhere in-game but the other player was assigned another shard?)
Much better would be if I could communicate between "rooms" in a limited way, for example by assigning each room a cell in a multiresolution grid (so that rooms can expand to cover sparsely populated areas) - and sending to each player in a room the updates (perhaps at a reduced rate) for players in adjacent cells. But as far as I know PlayerIO does not support any kind of messaging between rooms that would allow that. Please let me know if there's an option for that.
Also I would much rather be sending this in an email, but I understand that's a feature of one of your pricing tiers.
Cheers,
Reinier Vens