Object-Centric Drawing

One building object, across every drawing.

Object-Centric Drawing is a local-first browser prototype for navigating architectural PDF drawing sets by building object as well as by page. A physical object may appear in a plan, elevation, schedule, section, or detail. Object-Centric Drawing connects those visible occurrences through explicit user-created identity without modifying the source PDFs.

What it does

• Opens multiple local PDFs with fit, zoom, pan, view rotation, page thumbnails, page navigation, selectable embedded text, and in-document search.
• Marks rectangle, ellipse, and polygon occurrences using normalized page coordinates.
• Links occurrences to explicit category-neutral objects; matching labels never merge identity automatically.
• Navigates an object's representations across PDFs through Object Lens, Representation Board, and Drawing Set Map views.
• Separates an object browser from a properties pane. The browser groups by category, page or not at all, filters to the current page, and searches. The drawing can show labels, hide categories, dim or hide other objects, or hide all marks.
• Finds an object's other places: searches the embedded text of every attached PDF for its tag, such as D03, and shows each hit as a dashed box. One click links a hit. Nothing links on its own.
• Keeps editable notes with the whole project, one object, or one exact occurrence.
• Relates objects to each other: a card reader controls a door, a door is hosted on a wall and opens to rooms. Relations draw as arcs on the sheet and list in the properties pane. Drag from a mark's dot to relate, or use "Save, add more" to relate many objects at once. The Revit export can optionally add host wall and door room relations. Trace follows relations across pages, and the map marks pages with related objects. Export the project or a trace as an ONEXUS graph that merges with CDI's export, or open a live ONEXUS window that follows your selection. A door can say which room it opens into, and shows its rooms' data (such as finish) under Related data.
• Optionally imports the Revit export companion and shows populated instance/type parameters as searchable, read-only selected-object properties.
• Keyboard: step through one object's places with [ ], go back and forward through jumps with Alt + arrows, search objects with /. Press ? for the full list.
• Saves the object and note layer as portable versioned JSON beside the unchanged PDFs.
• Exports target-neutral evidence packages and an optional Door/Window Joinery AI handoff pack.

The mechanics have passed a bounded round-trip test. The product-value hypothesis still needs validation on a coordinated drawing set with owner-confirmed object identities; see ACCEPTANCE-2026-09-29.md.

Privacy and document safety

Object-Centric Drawing runs locally. Selected PDFs, rendered previews, object data, and search indexes remain in browser memory unless you explicitly export a project or evidence package. The application does not upload source documents.

This repository intentionally contains no sample architectural PDFs or project sidecars. Use only documents you are authorized to use, and do not attach confidential drawings to public issues.

Try it online

Open Object-Centric Drawing on GitHub Pages. PDFs are opened directly by your browser and are not uploaded to a server.

For offline use or local development, run the same application locally as described below.

Run locally

Requirements:

• Python 3 for the loopback static server.
• A current Chromium-, Firefox-, or WebKit-based browser.
• Node.js 26 or newer only when running the test suite.

On Windows, double-click start-server.cmd. On any platform, run:

python serve.py

Then open http://localhost:8765 and choose one or more local PDFs.

The supplied server binds only to loopback and provides the JavaScript-module MIME types required by the bundled PDF.js runtime. Do not open index.html through file://.

Save and restore

Export an .objdraw.json project beside its source PDFs. It stores fingerprints, document metadata, objects, occurrences, geometry, notes, and relations—not PDF bytes. A project can be imported before or after its PDFs are selected; identical renamed files can be matched by fingerprint.

Development

The project has no package dependencies or build step. Run the complete suite with:

npm test

Contributor guidance is in CONTRIBUTING.md. Product and architecture decisions are recorded in DECISIONS.md.

Project documents

• CONCEPT.md — product idea and terminology.
• TEST-RUN.md — one-hour test: object vs page navigation.
• PROTOTYPE-SCOPE.md — bounded experiment and exclusions.
• DATA-MODEL.md — project and occurrence model.
• OBJECT-EVIDENCE-PACKAGE.md — portable evidence contract.
• JOINERY-AI-HANDOFF.md — optional Door/Window adapter and trust boundary.
• AGENTS.md — implementation handoff and acceptance checklist.
• revit-addin/README.md — Revit add-in: export sheets to PDF with objects already marked (first spike, untested in Revit).

Project status

Object-Centric Drawing is an independent experimental project. It is not affiliated with or endorsed by an employer, software vendor, standards body, or the publishers of documents opened with it. It is not a BIM authoring tool, PDF editor, or replacement for professional review.

License

Object-Centric Drawing is licensed under the Apache License 2.0. Bundled third-party components retain their own licenses; see NOTICE and THIRD_PARTY_NOTICES.md.