R-Type

A networked, multiplayer remake of the classic horizontal shoot'em up R-Type, built in C++20 on top of a custom game engine.

Up to four players connect to a central authoritative server and fight waves of Bydos together. The project is split into reusable layers (an ECS based game engine, a UDP networking library and a Vulkan sprite renderer) and the R-Type client and server that are built on top of them.

Table of contents

• About the project
• Supported platforms
• Download a release
• Requirements
• Quick start
• Building
• Usage
• Project layout
• Documentation and useful links
• Contributing
• Authors
• License

About the project

This repository contains two programs:

Binary	Role
r-type_server	Authoritative, multithreaded game server. Runs the game simulation and replicates it to clients over UDP.
r-type_client	Graphical client. Renders the game, plays sounds and sends the player's inputs to the server.

Main characteristics:

• Client and server architecture. The server owns the game state and the clients comply with its decisions.
• Binary protocol over UDP. All in-game communication (entities, movements, events) goes through a documented binary protocol.
• Custom game engine. Rendering, networking and game logic are decoupled subsystems built around an Entity Component System, a scene manager and an event bus.
• Data driven entities. Entities are described in JSON blueprints under assets/descriptionEntity/, so new content does not require C++ changes.
• Time based simulation. Movement, animation and scrolling are driven by the elapsed frame time, never by CPU speed.

The project is developed as part of the Epitech Advanced C++ curriculum.

Supported platforms

OS	Prebuilt release binaries
Linux	x86_64, arm64
macOS	x86_64, arm64
Windows	x86_64

The CI builds and tests the server and the client on every platform above (see .github/workflows/build.yml). Windows arm64 is supported from source but no prebuilt binary is published for it yet.

Download a release

Every tagged release (v*) contains standalone binaries built by the CI. The assets, libraries and sprites are embedded in them, so the only thing you need installed is Vulkan (a Vulkan capable GPU and driver, plus MoltenVK on macOS) to run the client. The server needs nothing.

Files	Platform
r-type_server-linux-x86_64, r-type_client-linux-x86_64	Linux x86_64
r-type_server-linux-arm64, r-type_client-linux-arm64	Linux arm64
r-type_server-macos-x86_64, r-type_client-macos-x86_64	macOS Intel
r-type_server-macos-arm64, r-type_client-macos-arm64	macOS Apple silicon
r-type_server-windows-x86_64.exe, r-type_client-windows-x86_64.exe	Windows x86_64

chmod +x r-type_server-linux-x86_64 r-type_client-linux-x86_64   # Linux and macOS
./r-type_server-linux-x86_64 &
./r-type_client-linux-x86_64

They can be started from any directory. To compile the project yourself, see Building.

Requirements

Third-party dependencies

All other dependencies are downloaded automatically during the configure step. Nothing is vendored in the repository.

Dependency	Purpose	Provided by
Asio	Asynchronous UDP networking	vcpkg
nlohmann/json	Entity blueprint loading	vcpkg
GLM	Math	vcpkg
miniaudio	Audio playback	vcpkg
stb	Image loading	vcpkg
Vulkan headers and loader	Rendering backend	vcpkg
rtk ECS	Entity Component System	CMake FetchContent
rtk graphical	Window, rendering, input, audio	CMake FetchContent

The vcpkg manifest is vcpkg.json.

Quick start

If you only want to play, download a release. To build from source, see Building.

Building

To build from source see the online documentation

Usage

The binaries load their assets with paths relative to the working directory, so they must be started from the repository root (not necessary with embedded binaries).

Server

./bin/r-type_server [port]

Argument	Description	Default
port	UDP port the server listens on	4242

Client

./bin/r-type_client [-h host] [-p port]

Argument	Description	Default
host	Address of the server	127.0.0.1
port	UDP port of the server	4242

Start several clients to play together, up to four players per game. Each player gets a distinct ship color.

Controls

Action	Keyboard	Gamepad
Move	Arrow keys	D-pad or left stick
Shoot	Space	Right trigger (R2)
Confirm (menu)	Enter	Cross / A

Project layout

.
├── assets/              Sprites, sounds and JSON entity blueprints
├── lib/
│   ├── GameEngine/      Engine core: ECS components, systems, scenes, event bus
│   └── Network/         UDP transport, packet framing, connections, server
├── src/
│   ├── Client/          r-type_client: scenes, input, rendering adapters
│   ├── Server/          r-type_server: game simulation and replication
│   └── Common/          Code shared by both sides: protocol payloads, gameplay systems
├── docs/                Documentation website: Doxygen configuration and guides
├── tests/               Unit and functionnals tests
├── CMakeLists.txt       Build definition
├── Makefile             Build shortcuts
└── vcpkg.json           Dependency manifest

Documentation and useful links

• Developer documentation: architecture, engine and network guides, tutorials, technical study and API reference. Build it locally with make docs (requires Doxygen and Graphviz), the result is written to build/docs/html.
• Network protocol specification: every packet and message exchanged between clients and the server.
• Issue tracker: bug reports and feature requests.
• Pull requests: ongoing work.
• rtk-lib/ECS and rtk-lib/graphical: the ECS and rendering libraries used by the engine.
• vcpkg documentation: help with the package manager.

Contributing

Contributions follow a pull request workflow:

1. Create a feature branch from main.
2. Format the code with make format before committing.
3. Write commit messages that follow Conventional Commits, for example feat(server): broadcast monster spawns. The CI rejects commits that do not match the format checked by .github/scripts/check-commit-msg.sh.
4. Open a pull request against main and request a review from another team member.

Please open an issue before starting work on a large change.

Authors

Name	Contact
Arthur Gauthier	Arthur-gtr
Titouan Hochet	Titouanhct
Enzo Iffis	eiffis
Savinien Petitjean	savalet

License

This project is licensed under the GNU General Public License v3.0. See the LICENSE file for the full text.

R-Type is a trademark of its respective owners. This project is a non-commercial educational remake and is not affiliated with or endorsed by them.