Open Game Engine Exchange (OpenGEX)


The Open Game Engine Exchange (OpenGEX) format is a text-based file format designed to facilitate the transfer of complex scene data between applications such as modeling tools and game engines. The OpenGEX format is built upon the data structure concepts defined by the Open Data Description Language (OpenDDL), a generic language for the storage of arbitrary data in human-readable format.

Download OpenGEX specification, version 2.0 (OpenGEX.2.0.pdf)

The specification is also available in print on Amazon.

The OpenGEX format was created because Collada, the open standard that we all hoped would provide a well-supported asset exchange format, has proven to be an unreliable mess. The most common source of problems has been the poor quality of the Collada export plugins available for software such as 3D Studio Max and Maya, and we attribute this to Collada’s over-engineered design and its mutating under-specified format.

Compare OpenGEX, Collada, and glTF

OpenGEX Export Plugins

Official OpenGEX export plugins for 3D Studio Max, Maya, and Blender can be downloaded here. The source code for these plugins is provided under the Creative Commons Attribution-ShareAlike 3.0 Unported License.

The export plugins posted here support the following features:

3D Studio Max

OpenGEX export plugin version 2.0
(Last updated 29-Jan-2017)

This plugin may need to be recompiled from source for later versions of 3D Studio Max.


OpenGEX export plugin version 2.0
(Last updated 29-Jan-2017)

This plugin may need to be recompiled from source for later versions of Maya.


Blender export script version 2.0
(Last updated 29-Jan-2017)

OpenGEX Import Template

A free OpenGEX 2.0 import template can be downloaded through the following link. See the software license in the source code. This package includes project files for Visual Studio 2017, and the solution file can be found in the OpenGEX-Import/OpenGEX/ directory. This template is essentially the OpenGEX import plugin for the Tombstone Engine with the engine-specific parts stripped out. It reads an OpenGEX file and creates all of the structures necessary to construct a scene, but application-specific processing must be added in the appropriate places to support any other software.

Download OpenGEX Import Template
(Last updated 11-Apr-2017)

Revision History

Version 2.0. 29-Jan-2017

Version 1.1.2. 10-Dec-2014

Version 1.1.1. 1-Dec-2014

Version 1.1. 24-Nov-2014

Version 1.0.1. 26-Aug-2014

Version 1.0. 24-Sep-2013

Previous Specifications



OpenGEX was created by Eric Lengyel and is implemented in the art pipeline of the Tombstone Engine.

The OpenGEX file format is registered with the Internet Assigned Numbers Authority (IANA) as the model/vnd.opengex media type.

Copyright © 2013–2017 by Eric Lengyel

Creative Commons License
OpenGEX and the images on this page by Eric Lengyel are licensed under a
Creative Commons Attribution-ShareAlike 3.0 Unported License.
Based on a work at