jire / xlitekt

Open source Kotlin OSRS Emulator.

xlitekt

Introduction

XliteKt is an open-source, and forever open-source Kotlin based OSRS Emulator for educational purposes. Currently built around the game update: #202 (Nex)

The goal behind this project is to provide the community with a powerful, yet simple to use framework that is heavily documented.

Xlite is currently built by two developers:

• tyler27 (me)
• ultraviolet-jordan

Features

• Embedded HTTP server to deliver client configuration files.
• Cache data loading.
• Client cache files updating.
• Client game login.
• ISAAC and RSA.
• Full synchronization between connected clients and game server.
• Full clipping.
• Player updating.
• Npc updating.
• Basic UI support.
• Basic vars support.
• Basic commands support.
• And more!

Getting Started

Make sure to download the latest #202 cache version from one of the archives below. We don't push this to github for obvious reasons.

Download a cache and xteas (JSON) from archive.openrs2.org.

Place the cache you downloaded into the ./cache/data/ folder inside of the project. This path is configurable in the application.conf.

Generate RSA tokens and update your application.conf file

This will eventually be a gradle task to generate new RSA keys. For now, you can reference the rune-server thread: any-revision-enabling-rsa

Install the corresponding xteas inside of the map folder in resources.

Application configuration

Most everything will be setup and configured already for you around the build #202. So unless you're porting to a recent revision you'll really only need to worry about updating the RSA Keys in the application.conf file.

Configuration for ktor can be found in the ktor block.

ktor {
    development = false
    deployment {
        port = 43594
        watch = [ classes, resources ]
    }
    application {
        modules = [ com.runetopic.xlitekt.ApplicationKt.main ]
    }
}

Configuration for game related properties. You will need to generate your RSA exponent and modulus, as well as the packet sizes.

We will be writing a tutorial in the future for dumping packets sizes and other information from the current OSRS client as well as the gradle task to generate RSA tokens.

Please change the RSA tokens for a production based environment, these keys are just an example. Do not use this for anything other than local development.

game {
    benchmarking = false
    build {
        major = 202
        minor = 1
    }
    packet {
        sizes = [ 3, 8, 16, -1, -1, 8, 2, 1, 8, 0, 8, 8, 0, 2, 16, 16, 8, 9, 11, 8, 8, 7, 2, 4, 7, 4, -1, 7, 15, 8, -1, 8, 9, 7, 15, 6, -1, 3, 11, 15, 4, 8, 8, 8, -1, -2, 3, 3, 5, -1, -1, -1, -1, 7, 7, 0, 7, -1, -1, 3, -2, 3, 8, 3, 8, 0, 8, 4, 7, 11, 3, 6, 8, 11, 3, 8, 7, 4, -1, 2, 15, 7, 8, 3, 14, 3, -1, 10, 8, 13, 3, -1, 3, -1, 7, -1, 0, -2, -1, -1, 2, -1, -1, -1, 3, -1 ]
    }
    cache {
        path = "./cache/"
    }
    rsa {
        exponent = "74319506585812759823290259020934858088666404737094871101540670473424793671202076033582991318775440709937362678616598621443723414224839661646087632908361014054642952231258678163322462341878133664959918342102621655539431162351843502897522597279543226584696172903586455624355061037387268986011976499046968675073"
        modulus = "101152132894052393265886644489429469067887733993499471826334750806131431774995232950094045980615261210482740859538462033841944288877997111341162261129657268035424385776764492943939466200272309679088830878857767599863397432612329236019641861788901097158810527108145428907942159175673330991981851896173021952237"
    }
    resources {
        xteas = "/map/xteas202.json"
        interface_info = "/ui/interface_info.json"
        sequences = "/sequence/sequences.json"
        spot_animations = "/spot_animation/spot_animations.json"
        varps = "/var/varps.json"
        varbits = "/var/varbits.json"
    }
}

Maps

Maps are loaded using the xteas provided from OpenRS2, which follows this format:

[
 {
    "archive": 5,
    "group": 5932,
    "name_hash": -1153353684,
    "name": "l44_81",
    "mapsquare": 11345,
    "key": [
      52989138,
      -933733387,
      916753309,
      1765351430
    ]
  }
]

Benchmarking & Performance

XliteKt aims to be a very fast server which can easily handle thousands of players simultaneously and scales very well with better hardware. Even though XliteKt can run on low end machines, we highly suggest using a machine with a computer processor that has atleast 4 cores.

game {
    benchmarking = true
}

If you wish to benchmark this server on your machine, you can set this field in the application.conf file. Then use the ::benchmark command in-game.

Sample Benchmarking Results

- BenchmarkParallelActorSynchronizer
- AMD Ryzen 9 3900X 12-Core Processor               4.20 GHz
- Windows 11 Pro 21H2 22000.675 
============================================================
- Pathfinders took 15.417400ms for 2000 players. [TICK=1258]
- Pathfinders took 1.402100ms for 22472 npcs. [TICK=1258]
- Movement routing took 920.6us for all entities. [TICK=1258]
- Pre tick took 3.079500ms for 2000 players. [TICK=1258]
- Main tick took 24.448800ms for 2000 players. [TICK=1258]
============================================================
- Synchronization completed in 45.760100ms.
============================================================

Documentation

https://runetopic.github.io/xlitekt/