Pixar Universal Scene Description (USD)
What Is Universal Scene Description?
Universal Scene Description (USD) is an easily extensible, open-source 3D scene description and file format developed by Pixar for content creation and interchange among different tools. As a result of its power and versatility, it’s being widely adopted, not only in the visual effects community, but also in architecture, design, robotics, manufacturing, and other disciplines.
USD at NVIDIA
USD is the foundation for NVIDIA Omniverse™, a live collaborative platform that connects a wide variety of content creation tools to each other and to our real-time NVIDIA RTX™ ray tracer. Learn more about NVIDIA Omniverse and sign up for updates here.
NVIDIA has expanded upon USD by developing new tools, integrating technologies and providing samples and tutorials.
USD Pre-built Libraries and Tools
The USD libraries are only available in source form from Pixar, and building USD can be quite an adventure. We’re offering pre-built libraries as well as the accompanying tools (e.g., USDView) for download. This package will help you get started developing tools that take advantage of USD or get you up and running with USDView right away.
USD Sample Assets
USD scene with MDL materials rendered in Omniverse
You will need to review and accept Pixar’s license agreement before downloading the file.
Download from PIXAR
Getting Started with USD
NVIDIA Tutorials and Notes
These tutorials will help Python developers new to USD learn how to perform common tasks on the scene graph, as well as learn how to be more proficient with the USD documentation.
- USD Python API Notes
- Opening USD Stages Tutorial
- Prims, Attributes, and Metadata Tutorial
- Hierarchy and Traversal Tutorial
USD and Hydra Resources
Material Definition Language (MDL) Schema
USD is agnostic about the way material properties are represented. At NVIDIA, we believe artists should be able to author materials for cinema-quality rendering and have an automated process that produces simpler but still high-quality shaders in real time.
To achieve this, NVIDIA has developed MDL, an open-source, GPU-friendly Material Definition Language with an associated distiller that simplifies shaders for preview and virtual reality (VR) applications. The NVIDIA MDL SDK has been adopted by many application developers, including Adobe®, Allegorithmic, and Epic’s Unreal Studio.
To facilitate its use, we’ve created a specification (MDL Schema) for referencing MDL in USD and have developed Omniverse plug-ins to facilitate MDL-based workflows. MDL enjoys wide and increasing adoption in the design, visual effects, and gaming industries, among others.
MDL material examples