step_link & bevy_step_link: Direct STEP CAD file loading in Bevy (Pure Rust B-Rep parser)

[jorgeandrecastro]

Hey everyone!

I built a B-Rep geometric engine and a STEP parser (ISO 10303-21) in pure Rust, designed to integrate directly with Bevy without any heavy C++ dependencies (like OpenCASCADE).

The goal is simple: import CAD files (.step / .stp) on the fly into Bevy as standard Mesh assets, without needing external conversion tools like STL/OBJ, while preserving clean topology.

What it does:
step_link: The core calculation engine (Part 21 parser, B-Rep topology from Solid down to Vertex, and tessellation for planes, cylinders, and cones with hole handling via ear clipping).

bevy_step_link: The Bevy plugin and AssetLoader to load a .step file in a single line (assets.load("models/part.step")).

Tested on a real file (WallHook_30mm.stp, 63 faces, 744 triangles), loading and converting directly inside Bevy 0.20 happens instantly with clean topology.

Note: The project is actively under development. For my own comfort as a developer based in France, the documentation and README are currently written in French. If there is interest from the Bevy ecosystem or maintainers to integrate parts of this, I will happily translate everything into English!

Links & Open Source:
The project is dual-licensed under MIT / Apache 2.0.

GitHub Repository:https://github.com/jorgeandrecastro/step_link

Crates.io: https://crates.io/crates/step_link/0.1.0
And https://crates.io/crates/bevy_step_link

Feel free to take a look, test it out, or drop feedback and pull requests if CAD and industrial simulation in Rust are your thing!