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Torque 3D is a easy-to-use game creation platform. Architected from the ground up for maximum flexibility and performance across a wide range of hardware and built upon the Frontline award-winning Torque Game Engine Advanced, Torque 3D comes equipped with a full suite of tools and APIs to get your game to the finish line, no matter what your goals. Add publishing paths to PC, Mac, Xbox 360, Wii, iPhone, and the web, and you have the power to distribute games almost everywhere they are played.

OGRE (Object-Oriented Graphics Rendering Engine) is a scene-oriented, flexible 3D engine written in C++ designed to make it easier and more intuitive for developers to produce applications utilizing hardware-accelerated 3D graphics. Since 2001, OGRE has grown to become one of the most popular open-source graphics rendering engines, and has been used in a large number of production projects, in such diverse areas as games, simulators, educational software, interactive art, scientific visualization, and others. »

JMonkeyEngine3 it’s a free, open source game engine, made especially for Java game developers who want to create 3D games using modern technology. The software is programmed entirely in Java, intended for wide accessibility and quick deployment.

The OpenSceneGraph is an open source high performance 3D graphics toolkit, used by application developers in fields such as visual simulation, games, virtual reality, scientific visualization and modelling. Written entirely in Standard C++ and OpenGL it runs on all Windows platforms, OSX, GNU/Linux, IRIX, Solaris, HP-Ux, AIX and FreeBSD operating systems. The OpenSceneGraph is now well established as the world leading scene graph technology, used widely in the vis-sim, space, scientific, oil-gas, games and virtual reality industries. »

Atavism Online is a full fledged MMORPG Engine for use with Unity.

3DCrafter (formerly 3D Canvas) is a real-time 3D modeling and animation tool that incorporates an intuitive drag-and-drop approach to 3D modeling.