Use the LoadBalancing API to match players to a shared game session (called "room") and transfer messages synchronously, in real-time, between connected players across platforms. All client SDKs can interact with each other, no matter if iOS, Android, web, console or standalone.
With an AppId at hand you are ready to create a
LoadBalancingClient instance and call
It is best practice to extend the
LoadBalancingClient to modify callbacks and react to updates coming from the server.
Simply set your AppId and pick a region to connect to by using
Click here for a list of available regions.
The LoadBalancing API is built to integrate well with your game logic. You can fine-control when you want to handle incoming messages and how often you send anything. Internally, both directions are buffered until your game calls
Service() internally calls
DispatchIncomingCommands() until it returns false to dispatch all received incoming messages into your game logic. Calling
Service() also processes
SendOutgoingCommands which actually sends operations that your client called since the last
Service() triggers the callbacks
Games often use a game loop which calculates updates and then refreshes the screen. Call
Service() 10 to 20 times per second. If you don't call it, no "network progress" gets done at all.
Create a Game
To join or create a new room, aka game, invoke
OpJoinOrCreateRoom on your connected
This sets the room name and amount of players (default is 4) that are allowed in the room.
The client will enter the new room automatically.
OpJoinOrCreateRoom the room will be created before joining, if it doesn't exist.
Rooms exist until the last player left.
You can define
RoomOptions.CustomRoomProperties to set shared values for the room when you create it. The Custom Room Properties can be used (e.g.) to store the map name, level or the round duration. The keys of Custom Properties have to be strings.
Of course those values can be set and modified in the room as well.
You can select any of your custom properties to be shown also in the lobby, by setting the optional array with their names in
Properties showing in the lobby can be used for matchmaking and as filter for random matches.
TypedLobby.Default defines that the new room is listed in the Default Lobby. It lists rooms, which can be used for another form of Matchmaking.
Find a Game
Clients join games by name or ask Photon to find a perfect match.
Find rooms ...
- by Random: Matches players randomly. Optionally fills rooms or distributes players evenly.
- Use Filters in random matchmaking for better matching.
- by Listing: The lobby lists visible rooms to let players pick and join manually.
- that are Private: Join hidden rooms that you know the name of.
- or Parameterized: Customize random matching by defining expected properties.
With Photon Realtime, rooms' data can be saved and loaded easily. You need to setup webhooks to hook up Photon Cloud with an external web server.
Once setup, room states will be saved automatically for you. Use
OpReJoinRoom to re-join a room.
This feature makes asynchronous matchmaking and gameplay possible.
Read more about how to do this in our Persistence Guide.
Whatever happens on one client can be sent as event to update everyone in the same room.
Update your players with stats, positions or your current turn. Photon will send it as fast as possible (with optional reliability).
- Send messages/events: Send any type of data to other players.
- Player/Room properties: Photon updates and syncs these, even to players who join later.
Your event codes should stay below 200. Each code should define the type of event and the content it carries.
The event data in the example above is a
Hashtable. It can be a
byte or basically any data type supported by Photon's serialization (a
See Serialization in Photon for more information.
Whenever an event is dispatched the
OnEvent handler is called. An example is shown below.
Each event carries its
EventData.Parameters in the way your client sent them.
Your application knows which content to expect by the
Code passed with the
EventData (see above).
For an up-to-date list of default event codes look for the
EventCode constants in your SDK, e.g. within
ExitGames.Client.Photon.LoadBalancing.EventCode for C#.
Custom or Authoritative Server Logic
As is, without authoritative logic, Photon Cloud products already allow for a broad range of game types.
- First Person Shooters
- Racing Games
- Minecraft type of games
- Casual real-time games
- Asynchronous and synchronous games