USD

Universal Scene Description (USD) is a standard 3D format created by Pixar. It is the backbone of Omniverse and it’s something that you are bound to encounter when programming within in the Omniverse ecosystem. USD usually comes into play when you need to manipulate a Stage in some way, such as accessing or modifying Prims.

USD Example Code

Cameras

• Create an Orthographic Camera
  • Omniverse Kit Commands
  • USD API
• Create a Perspective Camera
  • Omniverse Kit Commands
  • USD API

Data Types

• Convert Between VtArray and Numpy Array

Hierarchy & Traversal

• Find a Prim by Name
• Find All the Prims of a Given Type
• Get the Child of a Prim

Inherits

• Add an Inherit

Layers

• Add a SubLayer
  • Omniverse Kit Commands
  • USD API

Materials

• Create an MDL Material
  • Omniverse Kit Commands
  • USD API
• Create a UsdPreviewSurface Material
  • Omniverse Kit Commands
  • USD API

Paths

• Concatenate a Prim Path
• Concatenate a Property Name with a Prim Path
• Get the Parent Path for a Prim Path

Prims

• Accessing Prims
  • Get a Reference to a prim
  • Getting cached prims
• Check if a Prim Exists
  • USD API
• Get the Current Selected Prims
• Select a Prim by Prim Path
  • Omniverse Kit Commands
  • omni.usd API

Properties

• Add a Relationship Target
• Check if a Property Exists
• Create an Attribute
• Create a Relationship
• Get the Value of an Attribute
• Get the Targets of a Relationship
• Set the Value of an Attribute

References & Payloads

• Add a Payload
• Add a Reference
• Create a Payload
• Create a Reference

Specializes

• Add a Specialize

Stage

• Get the Current Stage
• Set the Default Prim on a Stage
• Set the Stage Linear Units
• Set the Stage Up Axis
• Load a Stage

Transforms

• Compute the Bounding Box for a Prim
• Get the Local Space Transforms for a Prim
• Get the World Space Transforms for a Prim

Variant Sets

• Author Data for a Particular Variant
• Create a Variant Set
• Select a Variant for a Variant Set

Other USD References

We have comprehensive documentation on the Omniverse USD API

• USD API

Pixar’s formal specification API documentation

• pxr API