What Is a USD File: 3D Collaboration & Storage Format

What’s a USD file?

A USD, or Common Scene Description, file is a 3D asset format and way more. USD gives a framework for artists to create 3D belongings. Artists, administrators, and others can prepare, animate, gentle, and edit 3D objects in USD to create complete 3D scenes and worlds collaboratively.

As “Common Scene Description” implies, USD is a method to assemble and direct an animated scene. Creators can work with 3D objects and apply attributes, layers, and opinions in a single central information set. USD options schemas corresponding to geometry, lighting, shading, and physics, enabling 3D instruments to “discuss” to one another. USD is the primary open-source, public software program to compile and work with 3D belongings in varied codecs.

USD recordsdata are sometimes reusable for effectivity and scaling. For instance, an artist can begin with an outlined object like a automobile. They could change its form or shade, increase it, or divide it into separate components like wheels and headlights to provide them extra flexibility within the scene. This methodology allows advanced 3D scenes to take form with out recreating the wheel every time, so to talk. A single USD object is a “prim,” or primitive, that means it’s the smallest helpful piece you possibly can outline and customise for a venture. Creators and administrators use the prims to play their half within the context of your complete scene.

Along with USD recordsdata with the .usd extension, we even have USDZ (.usdz), USDA (.usda), and USDC (.usdc.) When somebody refers to a USD file, they normally imply .usd or .usdz. The remaining two extensions are a bit much less widespread. Under, we element these 4 file codecs and different USD-supported codecs within the USD File Formats section.

Key Takeaways

• USD is a 3D file format and a collaborative platform for storing and sharing scene info.
• 3D creators use USD when creating richly animated movies and video games, and 3D is taking up different makes use of – like serving to to construct the metaverse.
• USD’s future is determined by how the trade standardizes amongst competing codecs.
• Advanced tasks require an environment friendly 3D content material pipeline no matter file codecs, and USD gives that performance.

Why USD isn’t simply one other file format

USD differs from different 3D recordsdata as a result of it seamlessly shops and handles different codecs. Artists all over the world create recordsdata in USD or different codecs. Then they collaborate inside USD to edit, increase, and create advanced scenes and fashions. USD, developed by Pixar, is now open supply, permitting for extra widespread use.

Creators can use USD to concurrently work on the identical scene or venture, dealing with their respective items and instantly seeing the outcomes. For instance, totally different departments like animation, results, structure, and lighting can function collaboratively in USD to do their greatest work. As well as, the USD API permits a clean alternate with the totally different 3D functions.

Pixar developed USD to resolve the issue of working with unwieldy content material pipelines and workflows for ultra-detailed animated movies. These embody 1995’s “Toy Story,” the primary movie made solely with computer-generated imagery (CGI). Creators of the film used USD to encode information for interchanging and augmenting between digital creation apps. USD, additionally referred to as Pixar USD, stays the core of the corporate’s propriety Presto platform. In 2016, Pixar launched USD as an open-source project, making it out there to be used with different software program applications.

USD bought a giant increase when Apple adopted USDZ files, a zipped model of USD, as the first format for iOS functions. Different applications that assist USD embody Nvidia, Maya, 3DS Max, and Unreal Engine. You possibly can work properly in USD utilizing file varieties like .glTF, .mb (Maya), .max (3DS Max), and .uasset (Unreal Engine).

Why must you use the USD file format?

You’d use the USD file format for 3D visuals or results with exceptionally vivid element and realism. USD is helpful for large-scale tasks the place many artists can work independently and collaboratively. Additionally, it brings 3D file codecs right into a single information set, offering a extra environment friendly content material pipeline.

Alan Smithson, CEO and Co-founder of MetaVRse

Alan Smithson, a CEO and Co-founder of the 3D creation platform MetaVRse, explains, “Common Scene Description USD(Z) is a format created by Pixar and championed by Nvidia and Apple as the following commonplace 3D format. Not like glTF, which has been adopted by many of the world of 3D and XR, USD is just being utilized by a couple of, however very key gamers, together with full assist from Epic Video games. USD permits for full scene compositions to be saved and shared, whereas glTF is all about particular person 3D belongings. Each enable for advanced geometries, superior textures, transparencies, and inflexible or skinned animations.”

The 3D file format and program you select rely on particular corporations, tasks, and use circumstances. Extra persons are seeing why they may use USD, however extra generally, they’re utilizing glTF files, FBX files, OBJ files, GLB files, STEP files, and others. These codecs compete in sure circumstances however can be complementary. See our overview of 3D file formats to study which could be proper to your venture.

How are USD recordsdata used?

You should use USD recordsdata for a lot of features. For instance, artists create and retailer 3D objects in USD for advanced, detailed 3D scenes and fashions. 3D professionals use USD recordsdata and the USD framework to create or switch objects from varied codecs, construct scenes, and collaborate on the ultimate product.

Listed below are some particulars on methods individuals use USD:

• A major use of USD is to create, entry, modify, and retailer 3D objects, fashions, animations, supplies, lighting, and different info wanted for 3D scenes and tasks.
• USD is an effective method to switch 3D belongings and information between software program applications whereas retaining standardized USD information.
• Administrators and artists can use USD to work independently on various items of a posh venture or collaborate in actual time.
• Purposeful departments, like animations, results (FX), structure, and lighting, use USD for engaged on tasks.
• You should use USD to regulate items primarily based on their look in an general scene or venture. For instance, the lighting layer could immediate enhancements in your object design.
• USD gives choices for various items and the flexibility for individuals to share a hierarchy of “opinions” on these choices.
• USD is helpful for streamlining and growing large-scale tasks like movies and video games.
• You possibly can apply USD to different areas like 3D ecommerce, metaverse marketing, structure, product design, robotics, manufacturing, and to construct “digital twins” of bodily environments and belongings
• USD gives a typical language for constructing worlds within the metaverse, and that may work together seamlessly.

Who makes use of USD recordsdata?

USD’s essential customers are creators of animated movies and visible results. Recreation and metaverse builders are more and more adopting it, nevertheless it’s nonetheless not embraced because the common format. Others starting to make use of USD embody architects, robotics builders, and manufacturing designers.

Right here’s a more in-depth have a look at who makes use of USD recordsdata:

• Movie and Visible Results Artists: Creators and builders all over the world use USD to supply main films and visible results. Groups of artists from a number of design homes in disparate places collaborate to make immediately’s beautiful animated movies, like Pixar’s “Toy Story 4” and “Lightyear.”
• Recreation Builders: Epic Video games has adopted USD as considered one of its core instruments, and different gaming corporations could comply with.
• Metaverse Builders: Builders are constructing 3D worlds the place individuals can expertise and work together with leisure, gaming, e-commerce, advertising, and way more.
• Architects: Architectural CAD applications assist USD recordsdata.
• Robotics Builders: In robotics, builders are utilizing USD to simulate how autonomous robots, autos, and drones function in numerous environments, from a producing facility to a busy highway to the sky.
• Manufacturing Designers: Autodesk Inventor makes use of USD to retailer manufacturing designs.
• Product Designers: They use USD instruments to design and check merchandise nearly.
• “Digital Twin” Builders: These builders use USD to construct digital twins or digital replicas of bodily environments and occasions. Retailers, producers, and different companies use digital twins to simulate and check options and enhancements. Corporations already creating digital twins embody BMW, Lockheed Martin, and Siemens Vitality.
• 3D eCommerce: Builders can construct digital merchandise and experiences utilizing USD to provide clients a greater thought of how items will match into their lives.

What file codecs does USD assist?

USD helps its 4 core codecs:

• .usd – The principle format. It’s a plain textual content file and a binary file.
• .usdz – The “Z” on this extension means it’s a zipped USD file, making it straightforward to distribute and convert.
• .usda – It’s a plain textual content file.
• .usdc – It’s a binary file.

As well as, these file codecs can work properly with USD or USDZ, relying on the software program program:

• .mb – That is the extension for Maya’s platform file format.
• .max – That is the format for 3ds Max.
• .uasset – Unreal Engine makes use of this extension for its file format.
• .glTF – This can be a generally used format in gaming.

File codecs that work properly with USD

Typical USD workflow

USD workflow is determined by the venture’s complexity, objectives, and software program. In a serious movie, many artists will create “prims,” or 3D objects. The animation, FX, structure, and lighting departments collaborate to create the scene. At every step, creators make edits, produce choices, and vote with “opinions.” The director decides on what to make use of.

Right here’s a more in-depth have a look at Pixar’s USD workflow. Historically, it was linear, however not. With USD, creators can transfer into scenes with out ready for all of the items to be prepared. Artists can work independently and collaboratively, utilizing layers and opinions. This protects money and time, serving to them meet the deadline and funds. Creators can also use “early look” options that assist them envision all the chances for a scene, resulting in a greater last product.

USD pre-production steps

• Concept
• Story improvement
• Writing the script and storyboards
• Artwork consists of design, characters, units, props
• Modeling and shading

USD manufacturing steps

• Format
• Animation
• Simulation
• Results
• Lighting
• Sweatbox (aka dailies or rushes)
• Closing render

Professionals and cons of utilizing USD

USD’s professionals and cons revolve round your use case, technique, and objectives. USD’s professionals embody creating 3D recordsdata and complete scenes, exchanging totally different file codecs, and managing a collaborative pipeline. USD’s cons embody its complexity, massive file sizes, and lack of backward compatibility with older codecs.

Professionals of the USD format

• Create each 3D recordsdata and whole scenes with intensive element.
• Retailer and alternate recordsdata in numerous 3D codecs and USD-supported software program applications.
• Collaborate with groups of artists utilizing totally different file codecs on a large-scale venture, even on the similar time in real-time.
• Higher handle a big venture’s workflow, corresponding to a movie, recreation, or metaverse expertise.
• Entry or recreate reusable 3D objects for scaling a venture or initiative.
• It helps non-destructive enhancing, so work doesn’t disappear throughout enhancing.
• The “opinion” perform permits customers to vote on totally different choices, making a collaborative workspace.
• Edit or increase a file object in USD or one other 3D file format.
• Connect useful static and dynamic information to outline the scene.
• Fulfill the excessive expectations of immediately’s shoppers for realism and motion.

Cons of the USD format

• Whereas USD is tailored for advanced tasks like CGI movies and gaming, it might be too concerned and sophisticated for smaller 3D tasks utilizing different non-compatible file varieties.
• Many 3D creators are extra accustomed to utilizing different codecs like glTF, although the usage of USD is rising.
• It’s not backward appropriate with older file codecs like OBJ and FDX. OBJ is the default format for most simple 3D modeling. Though OBJ is extra fundamental and fewer detailed than USD and USDZ, it would work higher for a lot of one-time 3D tasks.
• In the event you’re utilizing Apple’s model of USDZ, remember that not all native USD options can be found.
• Information and scenes can turn out to be massive, making them slower to load and manipulate, though USD mitigates this with lazy loading.
• USD lacks Draco geometry compression, which glTF helps.

Professionals and cons of USD recordsdata

What instruments can you employ to view USD recordsdata?

Pixar has a USD toolset that you need to use to carry out totally different actions. View a whole listing of the USD toolset and how to use each. Moreover, corporations that assist USD present instruments to view and work with USD recordsdata.

• Pixar’s USDView: This open-source device means that you can load, view, and introspect USD recordsdata and scenes
• Nvidia: The corporate has USDView constructed into its Omniverse Launcher you could obtain and begin utilizing to discover working with USD.
• Apple’s Preview: You possibly can view and export a USD/USDZ file within the Preview app on a Mac.
• USD Supervisor: This light-weight, open-source platform allows USD viewing, enhancing, and managing USD recordsdata.
• Activision Free USD Shell Extension: This Home windows extension permits you to view and examine USD recordsdata in File Explorer.
• 3D USD Viewer: A free drag-and-drop internet app that renders USD recordsdata for viewing.
• Autodesk Maya: This 3D platform has an open-source USD plug-in that permits viewing, creating, and enhancing USD recordsdata in a Maya workflow.
• Autodesk 3ds Max: Autodesk additionally owns 3ds Max, an easier modeling platform that helps the format by means of the USD for Autodesk 3ds Max extension.
• Unreal Engine: This software program gives USD assist with its USD Stage and bi-directional Python workflows.
• Houdini Solaris: This 3D software program gives native USD assist for viewing and enhancing USD recordsdata.
• Foundry Katana: Helps USD in its software program for look improvement and lighting in CG tasks.
• Blender USD Exporter: This 3D platform helps some USD items however not but layers, variants, and skeletal animation.

What Software program Can You Use to Create and Edit USD recordsdata?

• Pixar’s USD instruments: Pixar’s full set of USD tools can be found as open supply on GitHub.
• Nvidia Omniverse: Nvidia has designed its platform on the USD framework.
• Apple USD/USDZ instruments: Apple developed USDZ in cooperation with Pixar as a distribution format to deal with USD and different codecs.
• USD Supervisor: This light-weight, open-source platform allows viewing, creating, enhancing, and managing USD recordsdata.
• Autodesk Maya: This 3D platform incorporates a USD plug-in that permits the viewing, creating and enhancing USD recordsdata.
• Autodesk 3ds Max: Autodesk additionally owns 3ds Max, an easier modeling platform that helps USD.
• Unreal Engine: This software program gives USD assist with its USD Stage and Python workflows so you possibly can import USD information, see its authentic construction, and edit it.
• Houdini Solaris: This platform gives native USD assist for viewing and enhancing USD recordsdata.
• Foundry Katana: Helps USD in its software program for look improvement and lighting.
• Blender: This 3D platform helps some USD items however not but layers or references

Examples of USD recordsdata

A scene from Pixar’s 2022 movie Lightyear, produced with USD. (Pixar press kit)

For different USD examples, see these references:

Additionally, see these examples and types of metaverse content.

USD information varieties

USD helps many information varieties, from belongings and bools to timecodes and tokens. They compose the USD language, defining all the pieces about 3D objects and scenes. In impact, creators use the information varieties to assist “solid” and “shoot” a scene.

Right here’s an in depth listing of information varieties supported in USD:

• asset: a resolvable path to a different asset
• bool: a boolean worth (true or false)
• double: a 64-bit floating level worth
• double2: a vector of two doubles
• double3: a vector of three doubles
• double4: a vector of 4 doubles
• float: a 32-bit floating level worth
• float2: a vector of two floats
• float3: a vector of three floats
• float4: a vector of 4 floats
• half: a 16-bit floating level worth
• half2: a vector of two half’s
• half3: a vector of three half’s
• half4: a vector of 4 half’s
• int: a 32-bit signed integer
• int2: a vector of two ints
• int3: a vector of three ints
• int4: a vector of 4 ints
• int64: a 64-bit signed integer
• matrix2d: a 2×2 matrix of doubles
• matrix3d: a 3×3 matrix of doubles
• matrix4d: a 4×4 matrix of doubles
• opaque: represents a worth you could’t serialize
• quatd: a double-precision quaternion
• quatf: a single-precision quaternion
• quath: a half-precision quaternion
• string: an STL string
• timecode: a double representing a resolvable time
• token: an interned string with quick comparability and hashing
• uchar: an 8-bit unsigned integer
• uint: a 32-bit unsigned integer
• uint64: a 64-bit unsigned integer

The way forward for USD recordsdata

USD’s future is determined by selections made within the coming months and years. USD has grown in recognition with its adoption by Apple and Nvidia. Nevertheless, glTF stays extra widespread. USD gives a normal language missing in different codecs, nevertheless it’s not essentially the ultimate phrase. Standardization particularly impacts metaverse improvement.

“Someplace between glTF and USD is the candy spot that can enable for common interoperability between 3D worlds and platforms,” says MetaVRse Co-founder Alan Smithson. “The Metaverse Requirements Discussion board, with over 2,000 members, is working diligently to create open, accessible requirements from which the world can construct.”

The Metaverse Standards Forum website states: “The Discussion board has initiated a pipeline of member-driven Exploratory and Working Teams that meet usually to create Charters and execute the tasks they outline. The teams presently embody the Metaverse Requirements Register Working Group, which is mapping the panorama of metaverse-related standardization actions and open requirements, plus exploratory teams which can be taking a look at 3D Asset Interoperability utilizing USD and glTF, Digital Asset Administration, Actual/Digital World Integration and Privateness, Cybersecurity & Identification.”

The Significance of 3D Asset Administration

The 3D trade is aware of it’s important to offer requirements and allow 3D worlds and platforms to function in unison. Likewise, extra corporations acknowledge that environment friendly 3D asset administration is significant to creating 3D experiences and feeding into 3D worlds. Creation is one factor. Managing content material pipelines is one other.

“Builders and creators are doing unbelievable work with present 3D instruments, however enterprise retailers with massive catalogs want a 3D platform to handle their 3D content material pipeline and workflow,” says Beck Besecker, Co-founder and CEO of 3D Cloud. “Whether or not growing 3D content material for in-store experiences or experimenting with metaverse marketing, a confirmed 3D asset administration system is important.”

How one can determine if you happen to want 3D asset administration

Not everybody wants 3D asset administration. It is determined by the scale, complexity, and objectives of your tasks. Ask your self or your group these six key questions when deciding on adopting 3D asset administration:

• Does our present means of dealing with 3D recordsdata ever fail to fulfill the wants of the group, shoppers, or clients?
• Have any group members ever duplicated work or unintentionally stepped on one another’s work?
• Have we run into issues with sharing or accessing 3D recordsdata?
• Will we typically lose observe of the assorted shifting items in a venture?
• Can we precisely assess and report on progress?
• Does our lack of a digital asset administration system restrict the tasks we’d love to do?

Share and scale your 3D content material with 3D Cloud

You possibly can create spectacular 3D content material in varied codecs for various functions. ­In the event you’re doing one-off tasks, perhaps that’s sufficient. However if you wish to create reusable content material at scale, alternate belongings in varied codecs, and publish to buyer functions, you want a 3D CMS. It’s the one method to handle massive volumes of 3D content material, apply enterprise guidelines for workflow, management your prices, and guarantee belongings are reusable.

Retailers, producers, and different industries are turning to 3D Cloud, a digital asset administration platform that shops 3D belongings generically. It gives a 3D content material pipeline and workflow system to ship belongings to WebAR functions, 3D product configurators, and way more.

3D Cloud can be trying to the longer term as a member of the Metaverse Standards Forum. If you’re a enterprise investing in 3D and its prospects, discover 3D Cloud.

Sonia Schechter is the CMO for 3D Cloud™.