3D scene exchange
USD Import & Export
Read and write USD, USDZ and USDA scenes with meshes, primitives, names, hierarchy, colors, metadata, materials and animations.
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Read and write USD scenes
The OCCT3D USD Import & Export SDK connects engineering applications with Universal Scene Description workflows. It supports reading and writing .usd, .usdz and .usda files, including geometry, scene organization, appearance, metadata and animation data.
Use it to import a scene for application processing or export scene data for downstream visualization and collaboration. Import and export are available in the same component.
Geometry, hierarchy, materials and animations
| Supported data | Read | Write |
|---|---|---|
| Meshes | Supported | Supported |
| Primitives | Supported | Supported |
| Names | Supported | Supported |
| Hierarchy | Supported | Supported |
| Colors | Supported | Supported |
| Metadata | Supported | Supported |
| Materials | Supported | Supported |
| Animations | Supported | Supported |
Applications can work with the organization and appearance of a scene as well as its geometry. Names and hierarchy identify its parts; metadata adds context; materials, colors and animations contribute to its presentation and behavior.
USD, USDZ and USDA support
All three listed extensions support both import and export. Specify the source and target extensions when connecting an existing pipeline, together with the geometry and scene properties that must be retained.
For a read-process-write workflow, inspect the imported scene, apply the required application operations, then write and reopen the result. Check hierarchy, names, appearance, metadata and animations in the receiving application, especially when the scene passes through multiple tools.
CAD-to-USD workflows
CAD data can enter a scene workflow through a suitable reader and mesh preparation step. Choose the source interface from the CAD exchange catalog, and define how the model will be represented in the USD output.
For a STEP-to-USD or Parasolid-to-USD pipeline, distinguish the precise source CAD geometry from the mesh or primitive representation used for scene delivery. Parasolid import supplies the corresponding source reader; Express Mesh provides control over CAD surface meshing.
The attributes retained by a complete conversion depend on both source and destination interfaces. An input without animations or materials does not gain those properties merely by being written to USD.
Evaluate USD exchange
Describe the input and output extensions, scene complexity, required metadata, material usage and animations. Include the target application and the checks that determine a successful exchange.
Discuss USD SDK evaluation or request scene and CAD integration services.
Convert USD to CAD and mesh formats
Import USD, USDZ or USDA meshes and supported primitives, then select the writer required by the destination. USD to STEP (STP), USD to STEP XML and USD to DXF carry mesh geometry into CAD document workflows. These routes do not reconstruct analytic BRep from scene meshes.
For polygonal delivery, compare OBJ, STL, PLY, glTF / GLB and JT. Select the scene state for static destinations and map only the hierarchy, materials and attributes the target can retain. Browse USD conversion guides.