usd2msd

This project is an offline converter for Omniverse-specific USD files to MSD.

This project is a sub-project. Unless explicitly specified, all paths in this README are relative to the project root, and all commands are assumed to run from that directory.

Setup Environment

This project uses pyproject.toml to manage dependencies. You can use any Python package manager that supports PEP 518. With uv, run:

uv sync

to install runtime dependencies and the default dev dependency group.

This project requires Python >=3.10, <3.14.

Hello World USD

Run the Python script using:

uv run examples/hello_world_usd.py

This converts hello_world.usda and loads it directly into MotrixSim via the PyO3 MSD binding. No intermediate file is written.

Usage

Converter.convert() returns an msd.World object (a PyO3 Rust object) directly:

from pathlib import Path
from usd2msd import Converter

converter = Converter()
world = converter.convert(Path("scene.usda"))
# world is a motrixsim.msd.World object, ready for use in MotrixSim

To use the world in MotrixSim:

import motrixsim as mx

model = mx.load_usd("scene.usda")  # internally calls Converter and builds the scene

Developer Guide

Update MSD Python Stubs

MSD types are exposed directly via PyO3 bindings from motrixsim.msd. When MSD structure in the main project changes, regenerate the Python stubs:

cd motrixsim-python/motrixsim-core
cargo run --bin stub_gen

Inspect Binary USD Files

To convert or flatten a binary USD file to readable USDA for inspection or debugging, edit and run:

uv run scripts/flatten_to_usda.py