Deciding who is player one and two in a round based game with Google Play Game Services

Question

I have a round-based Multiplayer game for Android that has been working over XMPP before, and I want to switch to Google Play Game Services. In the old version, there was an

Answer 1

This is a standard issue of selecting a leader from a bunch of unorganized nodes. There's some fairly advanced ways to do it, I'm sure. If you want to check out: Automatic selection of a leader in a cluster of nodes and hte Paxos algorithm.

Now...that being said, since you have a limit of 4 people, theres easier ways to do it. You could just treat their ID's as a number, and who ever has the highest ID is player 1, and descending in order. That would probably be the simplest way.

You could also have all the players submit a random roll and broad cast it. In the extremely rare case of a duplicate, you can have a reroll. Once everyone has made their rolls, and everyone has the same data, each individual client can determine the player order based on the value of the rolls.

I wouldn't do anything related to the order in the array however. I don't believe that's guaranteed in any circumstance.

Answer 2

I have solved the problem by comparing the player ids (which are random for each game):

String myid = mActiveRoom.getParticipantId(client.getCurrentPlayerId());
String remoteId = null;

ArrayList<String> ids = mActiveRoom.getParticipantIds();
for(int i=0; i<ids.size(); i++)
{
    String test = ids.get(i);
    if( !test.equals(myid) )
    {
        remoteId = test;
        break;
    }
}

boolean iMakeTheFirstMove = ( myid.compareTo(remoteId) > 0 );