◆ Rust · CAD → GIS

Turn DWG drawings into auditable GeoJSON.

A command-line converter that never presents unreferenced CAD coordinates as geographically correct — with per-entity diagnostics and deterministic, traceable reports.

Download v0.2.5 ↓ Get started → GitHub ★

dwg2geo — convert

$ dwg2geo convert corridor.dwg \
    --backend native --source-crs EPSG:31983 \
    --source-units m --output corridor.geojson

# 16,065 features · 4,533/4,533 accounted · 0 violations
wrote corridor.geojson
wrote report corridor.geojson.report.json

$ jq .native.accounting corridor.geojson.report.json
{ "model_space_entities": 4533,
  "top_level_accounted": 4533,
  "unaccounted": 0 }

Built for engineering data, not screenshots

Every design choice serves one goal: output you can trust and verify — no silent loss, no fake georeferencing.

🧭

Fails closed on CRS

Requires a source CRS or an explicit local-coordinate override. Drawing units are trusted only when the header is unambiguous; otherwise you state them.

🔎

No silent loss

Every unsupported, skipped, failed, or approximated entity is counted with a reason and sample handles. The accounting must balance — or it warns.

🦀

Pure-Rust native backend

Reads DWG in-process via acadrust — no LibreDWG or GDAL needed. A self-contained binary that runs anywhere.

📐

Real engineering geometry

OCS→WCS arbitrary-axis transforms, bulge arcs, deterministic curve tessellation, nested INSERT/MINSERT expansion, and hatch loops with holes.

🌍

PROJ reprojection & calibration

In-process PROJ reprojection with resolved units and axis order, plus local control-point calibration for drawings without a CRS.

🧾

Deterministic output

Same input, same GeoJSON bytes. A sidecar report records options, tool versions, source hash, bounding boxes, geometry checks, and outlier scans (its timing fields are the only run-to-run variation).

Entity coverage

The native backend converts the common civil/utility drawing set — and every one of the 44 acadrust entity types has a documented policy, checked by a test.

POINTLINELWPOLYLINEPOLYLINE 2D/3DARCCIRCLEELLIPSESPLINE3DFACESOLIDHATCHTEXTMTEXTINSERT / blocks

Bulge arcs and splines tessellate under an explicit chord tolerance; hatches nest into Polygons/MultiPolygons with holes; blocks expand with full transform composition and provenance. Deliberately unsupported types (rays, ACIS solids) and not-yet-converted types (dimensions, leaders, meshes) are reported, never guessed.

How it works

One header inspector, two backends, and a single writer — the pure-Rust path builds a CAD-neutral model that every transform and check operates on.

dwg2geo architecture: DWG input flows to the header inspector, the external LibreDWG/GDAL backend, or the native backend that builds a CAD-neutral model and writes GeoJSON with a report.

Conversion pipeline & key parameters

Fail closed on coordinates, resolve units, transform, validate, then write deterministically.

Conversion pipeline: coordinate policy, units, geometry, validation, and deterministic output, with the CLI flags at each stage.

Install & run

Grab a self-contained binary, install from your ecosystem's registry, pull the container, or build from source.

# Rust — crates.io (CLI or library)
$ cargo install dwg2geo

# JavaScript / WebAssembly — npm (runs in the browser, no native deps)
$ npm install dwg2geo

# Python — PyPI (wheels for Linux x86_64/aarch64, macOS, Windows)
$ pip install dwg2geo

Download v0.2.5 Linux x86_64 macOS arm64 macOS x86_64 Windows x86_64 all assets & checksums →

# Prebuilt release binary (Linux/macOS/Windows)
# from github.com/milkway/dwg2geo/releases

# or build from source (Rust 1.85+)
$ cargo build --release --features native-backend

# add PROJ reprojection (needs system PROJ ≥ 9.6)
$ cargo build --release --features native-reproject

# Slim container — native binary only, 28 MB, MIT-clean
$ docker build -t dwg2geo .
$ docker run --rm -v "$PWD:/w" dwg2geo \
    inspect /w/drawing.dwg --json

# check optional external tools
$ dwg2geo doctor

Inspect

Signature, version, units, extents, layer & entity histogram.

Choose CRS

Source CRS + units, or explicit local coordinates.

Convert

Native or external backend to deterministic GeoJSON.

Verify

Read the sidecar report — accounting, checks, bounds.

Transparent by construction

Multi-platform CI, a three-way independent audit, a verified architecture refactor, and a clean license posture.

✅

CI on every platform

fmt · clippy -D warnings · full test suite on Linux, macOS, and Windows, plus a PROJ-enabled reprojection job.

🛡️

Audited & verified

Independent correctness, completeness, and robustness passes; findings fixed and re-verified against a baseline build.

📦

SBOM & licenses

A CycloneDX SBOM and a full third-party license report ship with the repo; a CI gate blocks any new copyleft dependency.

Component	License	Distribution
`dwg2geo` + native deps	MIT / permissive	Redistribute freely — release binaries & slim container are MIT-clean.
`acadrust` (DWG reader)	MPL-2.0	File-level copyleft; binary distribution is unrestricted, no effect on dwg2geo's source.
LibreDWG (external backend)	GPL-3.0	Invoked as a separate process, never bundled — installed by the user, so no GPL propagation.