NVIDIA open-sources USD BRep, a library for CAD solid models in OpenUSD

USD BRep represents each solid as a boundary representation, or BRep, which describes the solid by the surfaces that enclose it. Those surfaces are built from NURBS, a mathematical way of describing smooth curves and surfaces that CAD software uses. Version 1.0.0 is on GitHub under the NVIDIA-Omniverse organisation and is licensed under Apache 2.0.

The Python package installs with pip install usd-brep and runs on CPython 3.12 on Windows or Linux. OpenUSD comes bundled with it, so it doesn’t need to be installed separately. A heal function repairs BRep definitions in USD files, and the repository includes STEP, IGES and JT models, common CAD file formats, for testing.

The repository’s tools carry the SMLIB name, in files such as smlib_gui.py. A CAD developer posting as @0xca0a, who says it has worked with SMLIB and its team for more than 20 years, described the code on X on 12 October as SMLIB, NVIDIA’s NURBS-based geometry engine, becoming open source. NVIDIA isn’t taking code contributions to the project, though it accepts issues and bug reports.