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Sponza licensing problem

Open echadwick-artist opened this issue 9 months ago • 3 comments

The Sponza asset is violating the terms of Crytek's license, and should be either removed, or it should be entirely replaced with the original source from Intel.

This was derived from Crytek's repository, which has this license: All "Crytek assets are covered under the CRYENGINE Limited License Agreement" which in turn forbids use of the asset for any purpose other than games developed within CryEngine.

Fortunately, the original asset was created by Intel, who made that version "available under the Creative Commons Attribution license." which is CCBY 4.0.

The current version of this asset should probably be removed, but it could be replaced with Intel's asset, which should be optimized since it currently weighs in a 3.6GB.

echadwick-artist avatar Mar 23 '25 20:03 echadwick-artist

There are some issues that involve the Sponza model ( https://github.com/KhronosGroup/glTF-Sample-Assets/issues/84 , https://github.com/KhronosGroup/glTF-Sample-Assets/issues/50 ) that might in the best case (at least partially) resolved by this.

The downloadable file is 3.6 GB, The bulk of this is textures (~2.5 GB), but that also includes some renders, and the MAX/USDA/FBX data. The glTF version only seem to add ~140MB to the textures.

But.... looking at the screenshot, it looks like the version here does include some of the "Sponza Add-on Packages" from that intel website - at least the "Colorful Curtains" and the "Ivy". This means that these would have to be "merged" into the main one (and it could end up with ... 3.6 GB or even more then... 😬 ).

javagl avatar Mar 24 '25 15:03 javagl

@echadwick-artist : I could not find anything in the Cryengine Limited License that restricted the use of assets to CryEngine games only. The license seems particularly unclear on the use of assets outside of the engine. It is clear on the use within a game. Please expand on your reasoning with references to the license (I'd like to figure out why I missed that).

DRx3D avatar Mar 26 '25 02:03 DRx3D

Until Eric chimes in, my take on this (with more disclaimers than usual: I'm not a lawyer):

The license at https://www.cryengine.com/ce-terms says...

  1. Grant of License

2.1.Grant: [...] Crytek grants to Licensee a [...] limited license [...] only:

[...] 2.1.4. publish, distribute, sell, sublicense or exploit in any other way Games in object code form only and only under terms consistent with and no less protective of Crytek’s rights than those contained in this Agreement in perpetuity.

Emphasis by me

One could construe this as: "You can use this stuff to create and publish games, but you cannot re-distribute the stuff itself". But for the case of the Sponza Model, there are some caveats: The "Description" on their site says

Previously only available on the Crytek page for use in CRYENGINE and other app testing, the CRYENGINE Sponza Sample Scene is a sample that developers can use to test lighting for their own games and setups.

On top of that: This model was originally not created by Crytek, so ,,, what do they have to say after all? What they are offering there is already just some ~"derivative work", at best, and the actual source of the PBR version is a derivative of the derivative. Not sure what to do with that.

(BTW: The link in the README, to http://www.alexandre-pestana.com/pbr-textures-sponza/ , does no longer exist (and could be removed when/if the model is replaced))

javagl avatar Mar 26 '25 12:03 javagl