LazyRef

A free image reference board that reads and writes PureRef .pur files. Android-first, in Rust.

LazyRef is an open-source reference board: you throw images onto a canvas, arrange them, and keep them around while you work. It speaks PureRef's .pur scene format directly, so boards made on the desktop open on your phone and back. File in, file out.

Android is the target. What exists today is the format core and a small desktop harness used to develop and test the board logic. The Android app is the next milestone.

Status

Piece	State
purcore — read/write PureRef 2.x .pur, read legacy v1.x	Done, tested against a golden corpus
Board core + dev harness (egui desktop)	Pan/zoom prototype, development tool only
Android app	Next milestone

Nothing here is a finished consumer app yet. The format layer is the part that's done and load-bearing.

What works

• Reads PureRef 2.x .pur scenes (SQLite-based container), including images, transforms, groups, strokes, notes and metadata.
• Writes them back byte-for-byte identical. On our golden-corpus tests, a scene that round-trips through the reader and writer produces the exact original file, checksum included.
• Reads legacy v1.x .pur files (the older binary format), read-only.
• Board canvas with cursor-pinned zoom, panning, and sticker transforms that follow the same semantics as PureRef boards.
• No Qt, no C++ runtime. The core crate pulls in rusqlite (bundled SQLite) and md-5, and that's it.

Building

You need Rust (stable). Nothing else for the core.

cargo test -p purcore     # format core: container, blobs, SQLite, legacy reader
cargo test -p lazyref     # board camera + sticker-transform invariants
cargo run  -p lazyref     # development harness (needs a display; works under xvfb-run)

The test suite includes golden .pur scenes captured from real boards, so the format tests exercise real files, not synthetic ones.

Layout

crates/purcore    .pur format core — container codec, blob codecs, SQLite store, legacy reader
crates/app        board app (egui) — the Android target will reuse this core
docs/FORMAT.md    what actually lives inside a .pur file

The .pur format

docs/FORMAT.md documents the container layout, the scene schema, and the binary codecs, as implemented and verified by purcore's test suite.

Roadmap

• Android app — native board UI, open/save .pur through the system file picker, share intents
• Render image stickers from .pur scene data in the board (today the harness draws placeholders)
• Save-back flow in the app (the core can already write; the app needs the UX around it)
• Desktop builds (no timeline — Android comes first)

Credits

LazyRef builds on the work of two projects and thanks both:

• PureRef-format — a Python toolkit for .pur files; our reference for format behavior.
• DroidRef — the Android reference-board app this project is a Rust rewrite of; the board interaction model follows it (including its sticker canvas, adapted from StickerView).

LazyRef is not affiliated with PureRef or its authors. "PureRef" is mentioned only to describe file-format compatibility.

License

MIT — see LICENSE.