A fully realized metaverse would be an interoperable digital universe where people can interact with one another through avatars in shared virtual environments. Building engaging metaverse environments requires delivering high-quality immersive content in lightweight, agile forms.
The Khronos Group has developed the glTF or Graphics Language Transmission Format, which is a standard file format for three-dimensional models and scenes in metaverse environments. It is intended to be a streamlined, interoperable format for the delivery of 3D assets, while minimizing file size and runtime processing by apps. Its creators have described it as the “JPEG of 3D.” glTF 1.0 was released in 2015, and Oculus and Microsoft quickly adopted it for their respective platforms.
glTF allows developers to convey complicated, high-quality images, models, and videos in XR environments while adding minimal weight to the system. The technology compresses 3D objects and their textures to preserve the quality of content while reducing the pressure on devices and systems. The file format supports static models, moving scenes, and animated content alike, giving developers plenty of scales to work with.
Furthermore, glTF is lightweight and easy to process on any device or platform, including mobile phones and web browsers. Its open-source nature and compatibility with existing tools and technologies make it an easy-to-use and efficient format. It even complements the majority of file formats already used in authoring tools.
The glTF file format is also highly complementary to USD (Universal Scene Description), a common tool used for 3D asset development. Companies like NVIDIA have invested heavily in the USD landscape for their omniverse environment, which has been built specifically with a focus on metaverse creation.
In 2017, a newer version of glTF called glTF 2.0 was made, and most people who make 3D models started using it instead. It has some improvements like better ways to make things look more realistic (PBR – physically based rendering), special features for moving faces (morph targets), and changes to make it faster (Sparse accessors).
Used correctly, glTF could easily become the standard file format for those investing in metaverse environments and digital twins. Going forward, innovative developers will look for ways to bring additional properties into the file format, such as sound and interactions. The open-source nature of USD and the consistent evolution of glTF will ensure the format continues to evolve and grow to match the changing needs of the metaverse. Just as the JPEG influenced the evolution of the visual internet we know today, the glTF could have a similar impact on the metaverse.