Open Source Game Engines

Crystal Space

Cross-platform

Crystal Space is a free cross-platform software development kit for realtime 3D graphics, with particular focus on games. (GPL)

Delta3D

Cross-platform

A well-supported and fully-funded open source project, Delta3D is a full-function game engine appropriate for a wide variety of modeling & simulation applications. (LGPL)

Irrlicht

Cross-platform

The Irrlicht Engine is an open source high performance realtime 3D engine written and usable in C++ and also available for .NET languages. (Zlib)

jMonkey Engine

Java

jMonkey Engine (jME) is a Java scenegraph API. Its primary focus is high-performance 3D gaming. (BSD)

OGRE

Cross-platform

OGRE (Object-Oriented Graphics Rendering Engine) is a scene-oriented, flexible 3D engine. (LGPL)

OpenSceneGraph

Cross-platform

The OpenSceneGraph is an open source high performance 3D graphics toolkit. (LGPL)

Panda3D

Linux, Windows, MAC OS X

Panda3D is a 3D game engine: a library of subroutines for 3D rendering and game development. Game development with Panda3D usually consists of writing a Python or C++ program that controls the Panda3D library. (BSD)