Open Source Game Engines
Sort By:
Game Engines
Browse free open source Game Engines and projects for Mac and BSD below. Use the toggles on the left to filter open source Game Engines by OS, license, language, programming language, and project status.
-
MongoDB Atlas runs apps anywhereMongoDB Atlas gives you the freedom to build and run modern applications anywhere—across AWS, Azure, and Google Cloud. With global availability in over 115 regions, Atlas lets you deploy close to your users, meet compliance needs, and scale with confidence across any geography.
-
Effortlessly manage macOS, iOS, iPadOS and tvOS devices across multiple clients and locations.Addigy solutions accelerate Apple adoption in any environment.
-
1
3D game engine (more powerful redesign of the Cube engine) and FPS game
">
-
2
A game engine for running Ultima7 on modern operating systems, plus a map-editor and other tools for creating your own mods and games.
-
3
QuakeSpasm
A modern, cross-platform Quake game engine based on FitzQuake.
QuakeSpasm is a *Nix friendly Quake Engine based on the SDL port of the popular FitzQuake. It includes some new features, important fixes, and aims for portability and 64 bit correctness. -
4
OpenRA
Real Time Strategy game engine supporting early Westwood classics
OpenRA is a free and open source real-time strategy game engine for early Westwood games like Command & Conquer: Red Alert. It is not just a clone of the original but is a recreation, with improved and rebalanced gameplay that modernizes the classic Command & Conquer strategy games. It provides a common platform for rebuilding and reimagining classic 2D and 2.5D RTS games (the OpenRA mods). This means that OpenRA is not restricted by the technical limitations of the original closed-source games: it includes native support for modern operating systems and screen resolutions (including Windows 10, Mac OS X, and most Linux distros) without relying on emulation or binary hacks, and features integrated online multiplayer. -
Fax.Cloud delivers encrypted, point-to-point faxing with guaranteed delivery and built-in audit trailsUnlike email or file-sharing tools, Fax.Cloud doesn’t bounce around the internet, exposed and vulnerable. It’s direct, encrypted, and verified. You get delivery confirmation, audit trails, and peace of mind, without the spam filters, metadata leaks, or cyber threats.
-
5
GemRB Game Engine
GemRB is a portable open-source implementation of the Infinity Engine
GemRB (Game engine made with pre-Rendered Background) is a portable open-source implementation of Bioware's Infinity Engine. It was written to support pseudo-3D role playing games based on the Dungeons & Dragons ruleset (Baldur's Gate and Icewind Dale series, Planescape: Torment). It should run on GNU/Linux, Microsoft Windows, OS X, possibly other UNIX derivatives and more. It is licensed under the GPL. -
6
ursina
A game engine powered by python and panda3d
ursina is an easy-to-use, open source game engine and framework for Python that is built on top of Panda3D, aiming to make game development approachable while still being powerful enough for real projects. It lets you create both 2D and 3D games, applications, and visualizations by writing concise Python scripts instead of dealing with a lot of low-level boilerplate. The engine is centered around an Entity-based architecture, where everything in the scene is an object you can easily configure and manipulate from code. Ursina focuses heavily on iteration speed, offering in-game reloading of code, textures, and models so you can tweak and test changes quickly. It includes many batteries-included features such as a mesh API for procedural geometry, built-in animation and tweening, pre-made controllers like FirstPersonController and EditorCamera, and a library of shaders and 3D primitives. -
7
Spring RTS Engine
Spring is a free RTS engine developed for Windows, Linux and Mac OS X.
Spring is a versatile 3D RTS game engine. Using extensively Lua for scripting game-specific code to make nearly every aspect of the engine customizable, from GUI, to unit AI, to pathfinding. -
8
Doomsday Engine
DOOM / Heretic / Hexen source port with enhanced graphics and UI
A portable game engine for classic first person shooters such as DOOM, Heretic and Hexen. Lets you enjoy the original games using modern technology, including high-resolution OpenGL graphics, 3D models, and dynamic lighting effects. -
9
VASSAL is a game engine for creating electronic versions of traditional board and card games. It provides support for game piece rendering and interaction, and supports play by email or over a live connection.
-
All-in-One Inspection SoftwareOptimize Frontline Operations: Elevate Equipment Uptime, Operational Excellence, and Safety with Connected Teams and Data, Including Issue Capture and Corrective Action.
-
10
F·W·K
3D game engine/framework in C, with Luajit and Python bindings now
3D game framework in C, with Luajit and Python bindings now. -
11
Matter.js
A 2D rigid body physics engine for the web
Matter.js is a flexible 2D rigid body physics engine written in JavaScript, designed for use in web applications to simulate real-world physical interactions within the browser. It offers a comprehensive set of physics features like gravity, collisions, restitution (bounces), friction, sleeping bodies, and constraint systems that enable developers to build interacting objects with realistic motion. This engine can power everything from dynamic interactive animations and educational simulations to fully fledged physics-based games, and it works across major browsers and devices. Through modules such as Matter.Body, Matter.Composite, and Matter.Constraint, developers can create complex scenes with multiple bodies, jointed structures, and collision responses. Matter.js is popular in the web development community due to its simplicity, extensibility, and rich documentation, allowing both beginners and experienced programmers to leverage physics without deep expertise. -
12
Amazon Lumberyard
Amazon Lumberyard is a free AAA game engine
Amazon Lumberyard is (or was) a free AAA-capable game engine developed by AWS, with deep integration into AWS cloud services and the Twitch streaming platform. It provided full source access and offered developers tools to build high-quality games and simulations with networking, rendering, physics and cloud backend features built in. The engine allowed game creators to hook into AWS infrastructure for multiplayer services, analytics, voice chat, and more, and leveraged Twitch to build live-stream-enabled experiences. Although Amazon has since archived the repository and transitioned focus to the open-source successor Open 3D Engine (O3DE), the project remains of interest as a large-scale example of cloud-enabled game engine architecture. Developers studying game tech or infrastructure integration can inspect how the engine’s subsystems were designed, including entity/component architectures, rendering pipelines and networked game services. -
13
Descent 3
Descent 3 by Outrage Entertainment
The Descent3 repository is the open source release of the Descent 3 game engine by Outrage Entertainment, maintained by the community under the GPL-3.0 license. It provides the full C and C++ engine source code, including the historically significant “1.5” patch that was previously created by developers and later stabilized by fans. The codebase covers the game’s rendering, physics, audio, networking, tools, and editor components, allowing enthusiasts to build, run, and modify the classic 6-degrees-of-freedom space shooter on modern systems. To actually play the game, users must supply their own original game assets, following instructions in the repository’s usage documentation. The project uses CMake and related modern tooling for cross-platform builds, with support for Linux and Windows among other environments. A dedicated community maintains the engine, publishes updated releases, documents internals on a wiki, and coordinates contributions via an active Discord server and GitHub. -
14
Aleph One is the open source continuation of Bungie's Marathon 2 FPS game engine. Aleph One plays Marathon, Marathon 2, Marathon Infinity, and 3rd-party content on a wide array of platforms, with (optional) OpenGL rendering, Internet play, Lua scripting, and more.
-
15
Castle Game Engine
Game engine supporting many 3D/2D formats and graphic effects
This project has moved to: - Our website https://castle-engine.io/ - GitHub repo: https://github.com/castle-engine/castle-engine/ Cross-platform 3D and 2D game engine for Object Pascal. Rendering and processing of game assets in glTF, X3D, VRML, Collada, Spine and other formats. Many graphic effects including shadows, shaders, mirrors, screen effects. Animation, collision detection, 3D sound. Extensible system of 3D objects, with out-of-the-box levels, items, intelligent creatures and more. Desktop, mobile, web plugin. Also home of view3dscene - our full-featured VRML/X3D browser. -
16
Clay
High performance UI layout library in C
Clay (short for “C Layout”) is a high-performance 2D UI layout library in C, offering a declarative, Flexbox-like layout model with microsecond performance. It features a single-header design, zero dependencies, and support for WebAssembly, making it lightweight yet powerful for responsive UI rendering. The Clay macro by default accepts an ID as its first argument, which is usually provided by the CLAY_ID() convenience macro. Elements can also be created with auto-generated IDs, by using the CLAY_AUTO_ID() macro. Element IDs have two main use cases. Firstly, tagging an element with an ID allows you to query information about the element later, such as its mouseover state or dimensions. Secondly, IDs are visually useful when attempting to read and modify UI code, as well as when using the built-in debug tools. -
17
Spartan Engine
A game engine with an emphasis on real-time cutting-edge solutions
SpartanEngine is a C++ game engine focused on cutting-edge real-time rendering and simulation, developed primarily as a long-running personal research project and now grown into a community-driven platform. It centers around a modern Vulkan renderer (with an in-progress DirectX 12 backend) and a fully bindless, unified deferred rendering pipeline designed to handle hundreds of millions of instances. The engine implements a wide range of advanced graphics features, such as atmospheric scattering, physically based shading, screen-space shadows and ambient occlusion, screen-space reflections, sophisticated shadow mapping, volumetric fog, and HDR output. It supports next-gen performance and image quality technologies including variable rate shading, dynamic resolution scaling, temporal anti-aliasing, and upscaling via XeSS 2 and FSR 3. Beyond rendering, SpartanEngine offers PhysX-powered physics, CPU and GPU profiling, a thread pool for parallel workloads. -
18
CoffeeMud
Full featured MUD server with all the trimmings.
CoffeeMud is a text-based virtual reality game engine (a MUD). It is a mature, full-featured Java codebase. It includes web (HTTP) and email (SMTP) servers, chat (IMC2 and I3) and web clients, and supports ANSI, MXP, and MSP.">
-
19
Rails is a Java game engine intended to play any of the 18xx series of turn-based board games For 3-6 players and set in the 19th century, these games allow players to step into the shoes of the robber barons and railroad tycoons of the time period..
-
20
A game engine for running Origin's 'Ultima 6' and 'Ultima Worlds of Adventure' games on modern operating systems.
-
21
Smokin' Guns is a GPLv2 licensed first person Western style shooter based on the Quake 3 engine (Id Tech 3) developed by a loosely knit team of developers and artists. This project represents the game engine.
-
22
AndEngine
Free Android 2D OpenGL Game Engine
AndEngine is a Java-based, open-source 2D game engine for Android, designed to make mobile game development easier by wrapping OpenGL (GLES) under a higher-level API. It abstracts much of the complexity of directly using OpenGL, letting developers more quickly build games with sprites, tilemaps, physics (via extensions), animations, and input handling, all within the Android ecosystem. Because it's tailored for Android, AndEngine integrates with typical Android project structure and lifecycle, although historically it was more aligned with Eclipse — meaning some adaptation might be needed for modern Android Studio projects. It enjoys a substantial community, many forks and extensions (for physics, tilemaps, multiplayer, live wallpapers, etc.), which increases its versatility — from simple casual games to more feature-rich 2D titles. -
23
boardgame.io
State Management and Multiplayer Networking for Turn-Based Games
The project implements a lightweight but powerful engine for creating turn-based games (board games, card games, turn-based strategy, etc.) in JavaScript. With boardgame.io, you define the game logic in pure functions: you describe how the game state changes when a move is made, and the framework handles all the rest (state management, synchronization, storage, multiplayer, etc.). This abstraction lets developers focus on the rules and mechanics rather than on networking, persistence or UI plumbing. It supports both local games and online multiplayer across clients, and can be used with different view layers — e.g., vanilla JS or a UI framework like React or React Native. It also offers tools to help with prototyping, debugging, logging, replaying game states, and even simple AI bots. Because of its simplicity and flexibility, boardgame.io is widely used for rapid prototyping of new game ideas or building full multiplayer board games. -
24
Haxima is an Ultima-like game engine (2D tile graphics) with combat, magic, NPC AI, an embedded scripting language, and in-game editing.
-
25
Gold Chest is a new game engine inspired by the old gold-box styled RPG games. My goal is to create a game with the same Look and Feel of the gold-box games while bringing to it newer graphics, sounds, music and network play.
