runescape classic web client

Usage no npm install needed!

<script type="module">
  import 2003scapeRscClient from 'https://cdn.skypack.dev/@2003scape/rsc-client';



a port of the runescape classic client (mudclient revision 204) from java to javascript.

this client is designed to work with rsc-server and RSCGo.


$ npm install @2003scape/rsc-client


after making modifications to ./src/, run $ npm install to install developer dependencies, then $ npm run build-dev to create a new bundle in ./dist/.

the ./dist/ directory contains everything you need to use the client. run $ npm start to start a simple HTTP server at http://localhost:1337. you may put optional arguments into the hash of the URL:


alternatively, you can manually invoke mudclient on your own canvas:

const mudclient = require('@2003scape/rsc-client');

const mc = new mudclient(document.getElementById('mudclient-canvas'));
mc.members = false;
mc.threadSleep = 10;

(async () => {
    await mc.startApplication(512, 346, 'Runescape by Andrew Gower');

if you don't want to host a separate websockets server, you can pass a Web Worker instance of rsc-server into the .server property instead.

see https://github.com/2003scape/rsc-server#browser-usage


features from earlier mudclients and/or inspired by modern third-party clients with their default values:

// hold down middle click and move the mouse to rotate the camera (only when
// camera is type manual)
mc.options.middleClickCamera = true;

// scroll panel lists and chatbox with the mouse wheel (and camera if zoom
// enabled)
mc.options.mouseWheel = true;

// click the compas to face north
mc.options.resetCompass = true;

// show roofs unless inside buildings
mc.options.showRoofs = false;

// use arrow keys (and mouse wheel if enabled) to zoom in and out
mc.options.zoomCamera = true;

// show the remaining experience until next level in skills tab
mc.options.remainingExperience = false;

// show your total experience in the skills tab
mc.options.totalExperience = false;

// censor chat and private messages
mc.options.wordFilter = true;

// support account registration, password changes and recovery within the
// client using jagex's older UIs
mc.options.accountManagement = true;

// display an "Fps: X" counter at the bottom right of the screen
mc.options.fpsCounter = false;

// retry logins when the server disconnects
mc.options.retryLoginOnDisconnect = true;

// experimental mobile support
mc.options.mobile = false;


make sure that wherever you host it, it's able to access ./data204/ via XHR for its cache files.


  • what is the purpose of | 0? why not use Math.floor()?

    number | 0 is an asm.js declaration for declaring a number as a 32-bit integer. the original java client used integer overflow techniques often, and this is the most performant method to declare them and accomplish the correct behaviour (javascript's Number is an IEEE 754; a java double).


Copyright 2021 2003Scape Team

This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more details.

You should have received a copy of the GNU Affero General Public License along with this program. If not, see http://www.gnu.org/licenses/.