do you mean put the code on the forums?
//Very useful website: https://www.gabrielgambetta.com/client-server-game-architecture.html
const HTTP = require("http");
const WebSocket = require("ws");
const UPDATE_TIME = 5; // in frames per second
class Player {
constructor(ws, id) {
this.x = 0;
this.y = 0;
this.ws = ws; // WebSocket connection
this.id = id;
ws.player = this;
}
}
var players = {}; //A list of all the players
//This is a dictionary. The key will be the players' unique IDs,
//and the values will be the players themselves
var requestQueue = [];
//Instead of processing each request as they're made,
//only actually process them a few times per second
//Put them in a queue for processing when it is time
//This is a utility function that sends data to all the clients
function sendToAllPlayers(dat) {
if (typeof dat === "object") dat = JSON.stringify(dat);
for (let pid in players) {
players[pid].ws.send(dat);
}
}
//This function handles information sent from a client
function handleRequest(player, req) {
if (req === "disconnect") {
delete players[player.id];
sendToAllPlayers({ type: "player_disconnected", id: player.id });
return;
}
if (req === "connection") {
sendToAllPlayers({ type: "player_connected", id: player.id });
return;
}
if (req.type === "position") {
player.x = +req.x; //unary plus operator converts things into numbers
player.y = +req.y;
return;
}
}
var lastUpdate = 0;
//This function handles all the requests in the request queue
function handleRequests() {
//get the time since the last update
var now = Date.now();
var dt = (now - lastUpdate) / 1000;
lastUpdate = now;
//console.log("Update");
for (let req of requestQueue) {
//console.log(req);
handleRequest(req[0], req[1]);
}
//clear request queue
requestQueue = [];
//send the positions of all the players to every player, if there are any
//to check if there are any players, check if the player list has keys
//using .length on the player list won't work because length only works on numbered arrays
//it is not an array, so it will not work.
if (Object.keys(players).length > 0) {
var posData = [];
for (let i in players) {
let player = players[i];
let id = player.id;
posData.push({
id: id,
x: player.x,
y: player.y,
});
}
sendToAllPlayers({ type: "positions", positions: posData, dt: dt });
//i need to give the client the server update timestep for entity interpolation
//entity interpolation is used to make movement look smooth, despite
//the positions only updating a few times per second. this works by
//simulating what happened for the player between server updates
//in the client by interpolating the player's position, which is why
//i must send the dt to the client
}
setTimeout(handleRequests, 1000 / UPDATE_TIME);
//Not using setInterval, since if it takes longer than usual to run the function,
//the function might execute while setInterval already ran the function again
//overlapping the two's execution :O
}
///////////////////
// Create Server //
///////////////////
/*
//I will create an HTTP server which the WebSocket server will use for connecting...
//I think only HTTP server
const https = HTTP.createServer((req, res) => {
res.statusCode = 400;
res.end("This is the HTTP server for the websocket. There is nothing here in terms of HTTP content.");
});
https.listen(8080, () => {
console.log("HTTP server running at port 8080");
})*/
const wss = new WebSocket.Server({ port: 8080 });
wss.on("connection", function(ws) { //When someone connections
//Player limit, up to 4 people
if (Object.keys(players).length >= 4) {
console.log("Server full!");
ws.close(1013, "Server is full -- max of 4 players"); //code 1013 means "Try Again Later"
return;
}
console.log("New socket opened");
//Generate random identifier ID for the player
var id = Math.floor(Math.random() * 99999);
var player = new Player(ws, id);
players[id] = player;
ws.on("message", function(msg) { //When the server receives a message from client
var json;
try {
json = JSON.parse(msg);
} catch(err) {
console.log("Invalid json data from " + id);
return;
}
requestQueue.push([player, json]);
})
ws.on("close", function() { //When the player disconnects
console.log("Socket closed");
requestQueue.push([player, "disconnect"]);
})
//Tell all other clients a new player joined
requestQueue.push([player, "connection"]);
//Send client's ID and other players' ids and position to the client
var posData = [];
for (let i in players) {
let p = players[i];
if (p.id === id) continue; //ignore own client
posData.push({
id: p.id,
x: p.x,
y: p.y
});
}
var initData = {
type: "init",
id: id,
players: posData
}
//console.log(initData);
ws.send(JSON.stringify(initData));
});
wss.on("listening", function() {
console.log("Websocket server listening on port 8080");
lastUpdate = Date.now();
handleRequests();
})
(it uses Node.js)
