uncad

An open-source Rust library that parses CAD files (DWG/DXF) into a model and exports that model as JSON, SVG or PNG. Read-only: it does not write DWG or DXF, and does not convert between them.

Quick start

git submodule update --init   # test fixtures only -- not needed to build (see "Platform")
cargo build --workspace
cargo test --workspace

let db = uncad::parse("drawing.dwg")?;   // same model for DWG and DXF (entities + tables)
println!("{} entities", db.entities.len());

let json = db.to_json(uncad::ToJsonOptions { pretty: true })?;   // the model, serialized as-is
std::fs::write("drawing.json", json)?;

let result = db.to_svg(uncad::ToSvgOptions::default());
std::fs::write("drawing.svg", result.svg)?;

let png = db.to_png(uncad::ToPngOptions::default())?;   // via to_svg(); no SVG touches disk
std::fs::write("drawing.png", png.png)?;

CLI

cargo run -p uncad-cli -- drawing.dwg                            # summary: entity count per type
cargo run -p uncad-cli -- drawing.dwg -o drawing.json --pretty   # export the parsed model
cargo run -p uncad-cli -- drawing.dwg -o drawing.svg             # render to SVG (model space)
cargo run -p uncad-cli -- drawing.dwg -o drawing.png             # render to PNG (via SVG)
cargo run -p uncad-cli -- drawing.dwg -o drawing.png --scale 2   # rasterize at twice the size
cargo run -p uncad-cli -- drawing.dwg -o drawing.svg --no-trim   # keep outlying coordinates
cargo run -p uncad-cli -- drawing.dwg -o sheet.svg --space paper # sheet borders / title blocks
cargo run -p uncad-cli -- drawing.dwg -o all.svg --space all     # every space in one document

Scope

DWG — read through LibreDWG (GPLv3+), bound directly via Rust FFI (bindgen). All versions.
DXF — read through the same LibreDWG engine, chosen by file extension. LibreDWG's own DXF importer is documented as working "for most objects", so it is less complete than its DWG reading (docs/CAVEATS.md).
Output — the parsed model as JSON (to_json), SVG (to_svg) or PNG (to_png). Writing DWG/DXF is not offered; the write API that existed in 0.1.0 was removed (see CHANGELOG.md).

Platform

Pure Rust plus native FFI. WebAssembly and the browser are not targets — the intended consumers are libraries and binaries (CLI, server, desktop app).

bindgen needs libclang, so LLVM/Clang has to be installed (Windows: winget install LLVM.LLVM, Ubuntu: apt install libclang-dev). The LibreDWG C sources are vendored into crates/libredwg-sys/vendor/libredwg/, so building does not need the lib/libredwg submodule. Running cargo test --workspace does: the real-file tests (png.rs, tests/dxf_pipeline.rs, tests/acis_sab.rs in uncad, and tests/documented_invocations.rs in uncad-cli) read fixtures from that submodule's test/test-data/. Clone with git clone --recurse-submodules, or run git submodule update --init in an existing clone. Builds and tests pass on Linux (x86_64-unknown-linux-gnu) as well as Windows.

License

GPLv3-or-later. LibreDWG (GPLv3+) is the only third-party component linked in, and its license carries over. Copyright and license details for third-party components are in docs/THIRD_PARTY_NOTICES.md.

Repository layout

lib/libredwg/            LibreDWG upstream, as a git submodule. Not used by the build --
                         it is the source vendor/ is regenerated from, and where the
                         real-file test fixtures (test/test-data/) come from
crates/
  libredwg-sys/          raw FFI (cc + bindgen). vendor/libredwg/ holds the unmodified
                         subset of C sources actually compiled (for publishing to
                         crates.io); shim/ holds the C accessors for opaque types, and
                         vendor-config/config.h stands in for autotools
  uncad/                 the safe API: parse() -> CadDatabase::{to_json,to_svg,to_png}()
  uncad-cli/             the CLI binary (uncad)
crates/*/tests/          integration tests against the public API. crates/*/examples/ are
                         manual-check tools, and #[cfg(test)] blocks inside src/*.rs are
                         unit tests -- docs/ARCHITECTURE.md's "Test layout" says which
                         belongs where
scripts/                 sync-libredwg-vendor.sh -- regenerates vendor/ after a submodule
                         update
samples/                 gitignored except its README -- drop any DWG/DXF in here for
                         manual testing, no license clearance needed. No automated tests
                         read from it
docs/                    architecture, known limitations, third-party notices