The Hunt for a Universal 3d File Format
File formats are a complicated matter, to begin with, but things get extra tricky when we talk about 3d data. The reason for the numerous 3d file formats is that each is designed to fulfill different use cases following different software requirements.
However, that makes data transfer between creative software and renderers difficult, which complicates the work of 3d artists. Аttempts have been made to address this widely spread necessity for a universal format, so we’ll track some major developments over the years.
To fit this into a readable piece, we’ll cover only some of the formats containing 3d mesh data, starting with…
Proprietary formats that tried to be universal
Certain formats, although developed for the needs of particular industry giants, have managed to offer a somewhat standardized means of exchanging complex 3d data. Here are the most influential ones:
3DS
The history and development of 3d file formats have followed the advancement of computer graphics and 3d modeling technologies. One of the first examples is 3DS, developed in the 90s.
It was initially introduced with Autodesk 3D Studio, which was later renamed to 3ds Max. While it’s less commonly used today and lacks interoperability with newer formats, it’s still widely supported by many creative software applications.
3DS is used for geometric data, materials, and lightning. However, as it was developed at a time when no one could imagine the computational power we have today, it has limitations. For example, all meshes have to be triangles, and the number of vertices and polygons per mesh can’t exceed 65,536, which makes it unsuitable for most modern projects.
OBJ
The OBJ format, created by Wavefront Technologies in the late 80s, is quite an old and basic format, but it’s still widely used because of its flexibility. In fact, it’s often the default file format for mainstream 3d modeling packages.
The text-based language makes it a good exchange format, as it can be easily exported and converted into other file types as needed. It can store detailed model data, such as geometry and texture mapping, but it’s notably larger than other 3D file formats that use binary to store information. That makes it more heavy to work with, so it’s utilized less and less for high-quality rendering and modeling.
FBX (FilmBox)
The Canadian software company Kaydara started developing the FBX format in the 90s. At first, it was a proprietary file format for their motion capture software, FLM, which stored bones, meshes, lighting, cameras, and geometry.
Later on, after it was adapted, it began supporting the visualization of 3d data. It was renamed to FilmBox with an FBX extension, and after a few more name changes, Autodesk acquired it.
It has become widely used in 3d animation, game development, and visual effects, as it can store complex data. The FBX file format can also be used with CAD files featuring NURBS coding to transfer models from CAD software to rendering operations. While the FBX files can be quite large in size, they’re still lighter to read than OBJ.
It also has some downsides, such as the need to use only the official SDKs because it’s a closed file format. It’s also becoming outdated and unsuitable for some use cases.
Actual attempts at universality
Despite the clear benefits a universal file format would have for artists, software providers may lack incentive for such a development. Proprietary formats often serve to lock users into specific systems, so companies tend to invest in them. However, there are instances where industry-wide standards have tried to emerge.
DAE (COLLADA)
COLLADA was initially released in 2004 by Sony Computer Entertainment as an intermediate format designed to transport data between different creative software. It later went under the management of the Khronos Group, and its XML schema for exchanging digital assets became open source.
It can be used for diverse 3d model data, including geometry, materials, lighting, and animation in the 3d modeling, animation, and game development industries. However, not all of its features are supported by all software applications.
gLTF (GL Transmission Format)
Another development from the Khronos Group was the GL Transmission Format, introduced in 2008. It’s also an open-source format that is regularly updated to fulfill the needs of major 3d studios.
It offers a way to keep the heavy files containing 3d models small and easy to transmit over the Internet. It’s notably faster to read than other formats and supports animation, which is handy for AR purposes.
On the other hand, the image quality is lacking, so the gLTF format is not well suited for the high-end needs of game development or special effects in the film industry.
USD (Universal Scene Description)
We’ve previously discussed the promise of the USD file format. It’s one of the newest developments in the CG industry and has gained the support of major players in the field. It’s open source and constantly upgraded so that it can achieve the long-awaited goal of having a universal standard in the field.
While USD can store lighting, bones, blend shapes, animations, different materials, scene hierarchies, and images with multiple topologies, it has limitations. It’s not backward compatible with OBJ or FDX files, and there’s still a need for wider software support.
At Connecter, we try our best to support all innovative and well-established formats alike so we can fit into anyone’s workflow. Our latest release introduced support for USD animation, as we recognize that this format has the potential to become an industry standard.
Other formats
As there are hundreds of formats, and each industry has its unique requirements, the quest for a universal standard remains unfulfilled. The BIM field, for example, has needs that the developments in the Entertainment industry can’t always meet.
Even if USD offers a solution for animation and VFX studios, engineers can’t utilize it for their projects. That’s why STEP is one of the most widely used formats for CAD modeling due to its interoperability. It can accurately transfer models of product design or anything with curved surfaces.
Wrap up
The crazy number of 3d file formats is a reflection of the individualistic pursuits of major software companies, each prioritizing their own goals over unified industry standards. Even though some proprietary formats offer somewhat standardized means within specific domains, they still lack full interoperability.
On the bright side, initiatives like OpenUSD emerge, signaling progress towards standardization. This collective investment of resources and effort is a sure sign that more and more major players are committed to optimizing workflows and creative practices.
If you’re looking for a way to take control of your digital assets, our DAM might be a good fit for your needs. Contact our support team to find out more about its organizational and collaboration features.
Disclaimer: Some of the images in the article are generated by DALL-E.
