// the take
A Rust/egui desktop (and wasm) tool for viewing, comparing, and aligning 2D occupancy grid maps in the ROS map_server format. Aimed at robotics engineers doing SLAM who need something between a dumb image viewer and the full weight of RViz. Compiles to native or wasm with identical feature sets minus file I/O.
The fixed-lens feature is genuinely useful for multi-map alignment — keeping a magnified view pinned to a coordinate while you drag another map around is a workflow detail that shows real field experience. The crate split (maps_io_ros, maps_rendering, maps) means the I/O library is independently reusable and the GPU texture work is separated from app logic, which is a good call for a GUI tool. Snapshot-based UI regression tests using egui_kittest mean visual regressions are caught in CI, not in the field. The WASM build parity is solid — same UI, only filesystem access differs, and it's documented honestly.
Hard-locked to ROS map_server YAML + image pairs — if your SLAM stack exports anything else (occupancy grid as PGM without YAML, GeoTIFF, PNG with embedded metadata), you're writing a converter first. 116 stars suggests early-adopter territory; the session file format and API are not stable, so anything you script around it today may break on the next release. No undo/redo for pose alignment — if you've spent 10 minutes manually nudging a large map and misclick, you're back to where you started. Single-author project with no public roadmap, so feature requests are a coin flip.
We read the README, the directory tree and a key source file in July 2026. Nobody pays to be listed. How we judge →