Besides a valid Game Maker: Studio license you will also need to host a master server somewhere. “Somewhere” means it has to be reachable from the internet! [Ports must be opened] Also please note that this only works with UDP game servers! - Setting up UDP game servers in Game Maker is very differnt from TCP game servers since UDP is connectionless. If you need help, contact me!
The server GMnet GATE.PUNCH that is needed to connect clients and servers is free software and the source code can be found on it's product page.
It is written in java and you can either download the binarys or the well-documented source code. Adjust the mediation server to fit your needs or write your own (you can find the communication “protocol” below) It comes with everything that is needed for TCP and UDP communication with Game Maker: Studio and can also be used to create a dedicated multiplayer server or something elese.
You need to host this server yourself. If you can’t right now, contact me, I can host a server for you for testing purposes. For the demo you can also connect to the default IP and port (please note that this demo server might be down).
If you need more help setting up the server, check out the tutorial page of GMnet ENGINE on this topic.
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GameMaker: Studio is owned by YoYoGames. GMnet is not affiliated with YoYoGames.
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