Crate ggrs[−][src]
Expand description
GGRS
GGRS (good game rollback system) is a reimagination of the GGPO network SDK written in 100% safe Rust 🦀. The callback-style API from the original library has been replaced with a much saner, simpler control flow. Instead of registering callback functions, GGRS returns a list of requests for the user to fulfill.
Structs
Represents a serialized input for a single player in a single frame. This struct holds a buffer where the first size bytes represent the encoded input of a single player.
The associated frame is denoted with frame. You do not need to create this struct, but the sessions will provide a Vec<GameInput> for you during advance_frame().
Represents a serialized game state of your game for a single frame. The buffer buffer holds your state, frame indicates the associated frame number
and checksum can additionally be provided for use during a SyncTestSession. You are expected to return this during save_game_state() and use them during load_game_state().
An Arc<Mutex<GameState>> that you can save()/load() a GameState to/from. These will be handed to the user as part of a GGRSRequest.
The NetworkStats struct contains statistics about the current session.
A P2PSession provides a UDP protocol to connect to remote clients in a peer-to-peer fashion.
A P2PSpectatorSession provides a UDP protocol to connect to a remote host in a peer-to-peer fashion. The host will broadcast all confirmed inputs to this session.
This session can be used to spectate a session without contributing to the game input.
During a SyncTestSession, GGRS will simulate a rollback every frame and resimulate the last n states, where n is the given check distance.
The resimulated checksums will be compared with the original checksums and report if there was a mismatch.
A messages that NonBlockingSocket sends and receives. When implementing NonBlockingSocket,
you should deserialize received messages into this type and pass them.
Enums
This enum contains all error messages this library can return. Most API functions will generally return a Result<(),GGRSError>.
Notifications that you can receive from the session. Handling them is up to the user.
Requests that you can receive from the session. Handling them is mandatory.
Defines the three types of players that GGRS considers:
A session is always in one of these states. You can query the current state of a session via current_state().
Constants
The maximum number of bytes the input of a single player can consist of. This corresponds to the size of usize.
Higher values should be possible, but are not tested.
The maximum number of players allowed. Theoretically, higher player numbers should work, but are not well-tested.
The maximum number of frames GGRS will roll back. Every gamestate older than this is guaranteed to be correct if the players did not desync.
Internally, -1 represents no frame / invalid frame.
Traits
This NonBlockingSocket trait is used when you want to use GGRS with your own socket.
However you wish to send and receive messages, it should be implemented through these two methods.
Messages should be sent in an UDP-like fashion, unordered and unreliable.
GGRS has an internal protocol on top of this to make sure all important information is sent and received.