MonumentumJS

Realtime game server backend written with TypeScript on top of Node.js and using WebSockets for transporting. Implements fixed timestep simulation model, provides functional for game rooms management and peers handling. Suitable for client-server authoritative applications.

Used modules

• uWebSockets for WebSocket server
• nanotimer for fixed timestep loop

Call npm install uws nanotimer inside TypeScript outDir (can be changed in tsconfig.json) to install modules required for a base server. If you want to run included example application you should also install p2 module for game physics calculation.

For example:

cd js
npm install uws nanotimer p2

Server architecture

• Service is a WebSocket server and a game room manager. It accepts sockets, wraps them into Peer structure and emits events to hosted game rooms (and lobbies) for this peer. User must subclass Service and implement a matchmaking mechanism for players separation. Service will pass all socket events directly to the room assigned to it.

• Room is a shared game session. A Peer will be placed inside a game room after succesful connection to server. Room contains all information about it's peers, assigns unique IDs to them and provides some event callbacks to the used, such as: on peer join/on peer leave/message received. Implements a fixed timestep loop that can be initiated using setTickTime(...) that accepts seconds. User also must implement onTick() and place all room's game logics inside it's body.

• Peer is a structure, that describes the connected socket. Contains the socket itself and a Room that it has been assigned to. User can extend Peer with interfaces to link additional information about particular player. After getting assigned to particular game room, the Peer gets unique ID.

Service and Room are abstract classes, user must subclass them and provide own realization.

How to use

Make sure you have installed required modules for MonumentumJS. The engine comes with simple game example that realizes 2D physics based player movement in empty 2D space and uses simple binary protocol for communication between peers and server for such events like: peer joined/peer leaved/peer's state update/receive peer's input. The example requires p2 module to be installed. You can build the example project with TypeScript compiler and use node to run the App.js by default located in js dir after succesful compilation. To create youw own project should instantiate subclassed Service with proper matchmaking, add some Rooms to it and run myService.run(port)