Specific game setup with Game Center

Does anyone know a way to setup GKMatchRequest in a way t开发者_如何学编程hat all players have the same properties? For the purposes of Game Center's auto-matching. GKMatchRequest.playerAttributes seems to be useless here.

A simple example would be: game allows you to pick couple of different maps, and you want to auto-match with other players that have picked the very same map.

Fallback solution is to have map voting after auto-matching, but that's something I'd like to avoid. Any thoughts? Appreciated in advance.

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I hate to answer my own question, but I've finally, accidentally found it. It's in GKMatchRequest documentation. It seems GKMatchRequest.playerGroup provides the functionality I was looking for. Hope this will be of any help to anyone as poor at careful documentation reading as I am ;)