Hi Milad,

 Thanks for contacting us regarding your Unity 3D game engine file format compatibility questions.

There are several differences between the three file formats you mentioned.  3ds is a legacy file format supported by 3D Studio on the DOS platform, versions 1 to 4 (in the late 90’s).  When the 3d Studio software made its way onto the Windows platform, with 3D Studio Max and then 3ds Max, the native file format for the program changed from .3ds to .max, however 3ds Max versions today still support the legacy .3ds file format.  Unity only supports mesh data coming from the .3ds file format.  OBJ is a static 3D geometry file format developed by Wavefront technologies.  It is still a popular file format used for exporting/importing 3D geometry, however it does not support animation data, and so like .3ds, Unity only supports mesh data coming from the .obj file format.  The FBX file format supports animation and 3D geometry, amongst a number of other things.  It is a current technology that is developed, tested, supported and documented by Autodesk, and the technology is also used/supported by a large number of companies/products outside of Autodesk.  FBX technology can be best summarized by this article on Wikipedia: http://en.wikipedia.org/wiki/FBX.  Don’t worry, I wrote the article; the content is accurate.  Since FBX is the most current and updated data exchange technology, I would recommend reading/importing .3ds and .obj file formats and writing/exporting .fbx files when using our FBX Converter.  If you run into any technical issues in doing so, please do use our fbxplugins@autodesk.com email alias to contact me and we’ll investigate.  You can find more information and downloads for FBX technology here: www.autodesk.com/fbx.

We, Autodesk Media & Entertainment, have worked with Unity to ensure that the FBX file format is well supported by their game engine.  Currently, with Unity 3D 2.6.1, if you export from any 3D software that supports the FBX file format (up to our latest released version, FBX 2010.2.1) , you’ll have strong compatibility with Unity’s game engine.  If you save your file in Autodesk 3ds Max or Maya natively (.max or .mb/.ma respectively), you will have the same strong compatibility with their game engine, as they are using FBX technology to support/convert that native 3D data from those packages.  If you’re looking to support just static 3D geometry without animation data or FBX-supported data, it’s also fine to use the OBJ file format, as Unity supports that format.  For more information about Unity’s file format support, please refer to their website: http://unity3d.com/unity/features/asset-importing.html.

 I hope this information helps and let us know if you have further questions or need further clarification on something regarding our technology.

Thanks,

TREVOR ADAMS | QA LEAD

.FBX TECHNOLOGIES GROUP

AUTODESK®

MEDIA & ENTERTAINMENT

10 Duke, Montréal QC, Canada    H3C 2L7