arc Documentation
arc is an open-source 3D CAD modeling application engineered for makers,
designers, and engineers. Built with a high-performance Rust B-rep geometry kernel and a
sleek WebGL viewport, it runs natively on Windows, macOS, and Linux.
01Getting Started
Install prebuilt packages or compile from source, then tour the modern interface: Shapr3D-style tool dock, 3D ViewCube, and floating selection HUD.
02Modeling
Parametric primitives, 2D sketch loops, direct face extrusion, solid operations (fillet, revolve, sweep, loft), layers, and native .arc documents.
03Navigation
Orbit, pan, and zoom controls; the interactive 3D ViewCube; infinite coordinate axes; dynamic drafting grid and snapping.
04Keybinds
Complete reference for default keybindings, quick action keys, and creating custom keyboard profiles in Settings.
05Plugins
The sandboxed Lua plugin system: document lifecycle events, the arc scripting API, and examples.
06Themes
Built-in themes (Deep Graphite and Glass), importing and exporting custom theme JSON, and the sixteen color tokens.
07Automation
The local automation bridge: controlling arc via JSON commands over bridge.json and the bundled Model Context Protocol (MCP) server.
About the Architecture
arc combines modern web technologies for an ultra-responsive UI with a native Rust geometry
kernel (forked from the open-source truck B-rep engine). The Rust
kernel manages document state, topological entities, parametric history, STEP import/export,
and robust mesh tessellation.
The frontend communicates with the Rust engine through strongly typed Tauri IPC commands.
The modeling workflow is direct: draw sketch loops on any plane, extrude planar faces into solids,
apply fillets and offsets, and modify geometry without modal interruptions.
Documents use transparent native .arc files (JSON) with full STEP,
OBJ, and binary STL support.
arc