Babylon.js is a powerful, beautiful, simple, and open game and rendering engine packed into a friendly JavaScript framework.

A complete 3-D game development suite written in Java.

The multiplayer game engine

Terasology - open source voxel world

An OpenGL RTS game engine written in C

The ioquake3 community effort to continue supporting/developing id's Quake III Arena

Amazon Lumberyard is a free AAA game engine deeply integrated with AWS and Twitch – with full source.

3D Procedural Game Engine Using OpenGL

Tiny OpenGL Wrapper / 3D Engine in C++

Cross-platform port of Arx Fatalis, a first-person role-playing game

Nebula is an open-source and free-to-use modern C++ game engine.

Fun with WebGL 2.0 Youtube Tutorial Series

ET: Legacy is an open source project based on the code of Wolfenstein: Enemy Territory which was released in 2010 under the terms of the GPLv3 license.

The BombSquad Game Engine

An Open Source C# 3D Game Engine under MIT license, inspired by Unity and featuring a complete editor

Archived repository. For current repo, see: https://github.com/etlegacy/etlegacy

WeDot 是一个专注于技术和用户体验的多平台 2D 与 3D 游戏引擎，开发者可以把注意力集中在游戏开发本身，而非繁杂的技术细节。

Source code for cross-platform OpenGL gaming engine

Multi-platform game where you feed well dressed animals with sushi

Blazium Engine – Multi-platform 2D and 3D game engine