Real-Time Collaboration

Share a model with a link and work on it together — live cursors, a shared spatial tree, synced edits, and a presence roster. No accounts: access is carried entirely by the share link.

How it works in one line

The model lives in a CRDT room (IFCX-native). The owner seeds it from their open model; everyone else joins by link and the viewer reconstructs the model from the room — so a recipient needs no file, just the link.

Enabling collaboration

Collaboration ships behind a flag so it stays out of the way until you want it.

How	What
Build env	Set VITE_COLLAB_ENABLED=true (and a server URL — see below) when building/serving the viewer.
Per-browser (dev)	In the browser console: localStorage.setItem('ifc-lite:collab:enabled', 'true'), then reload.

When enabled, a Share button appears in the toolbar (it's active once a model is loaded). To sync across machines you also need a collaboration server; without one the feature runs local-only (one browser, multiple tabs) — handy for trying it out.

Sharing a model (owner)

1. Load a model.
2. Click Share in the toolbar.

3. Choose what anyone with the link can do:

   Access	Can…
   View	See the model, the spatial tree, properties, and other people's cursors.
   Comment	…also add issues and markups.
   Edit	…also change properties and geometry.

4. Click Copy and send the link. It looks like https://…/?room=<id>&t=<token> and expires after 7 days.

Opening the dialog puts you in the room as admin and starts sharing your model into it. You can re-copy a link at any access level, and you stay admin for the room.

Joining (recipient)

Open the share link — that's it, no account needed. The viewer joins the room and reconstructs the model:

• the 3D model renders,
• the HIERARCHY panel and explorer (Spatial / Class / Type) populate,
• clicking an element fills the INSPECTOR with its attributes and properties,
• edits made by others appear live.

Recipients work from the room, not a file

A recipient never downloads the original IFC. The model is rebuilt from the shared room as IFCX, with geometry streamed as content-addressed blobs. This works for both IFC5/IFCX rooms and legacy STEP (IFC2x3/IFC4) rooms.

The room panel

While you're in a room, a people button appears in the toolbar (with a live participant count). It opens the Room panel:

• Connection + room id — a live status dot (Live / Connecting / Offline).
• Roster — everyone present: colour dot, name, role badge, and current activity (active / idle / measuring …). You're marked (you).
• Copy invite link — mint and copy a fresh link.
• Leave room — disconnect and return to solo editing.
• Admins additionally get:
  • Revoke link — invalidate the last share link you handed out; anyone trying to join with it afterwards is refused.
  • Remove (hover a peer) — disconnect a participant; their link is revoked so they can't immediately rejoin.

Roles

Roles are baked into the share link and enforced by the server (when one is configured), so a link's holder can't escalate their own access.

Role	Read	Comment	Edit	Manage
Viewer	✓
Commenter	✓	✓
Editor	✓	✓	✓
Admin (owner)	✓	✓	✓	✓ (revoke / remove)

Privacy & limitations

• The share link is the credential — anyone with it gets that role until it expires (7 days) or an admin revokes it.
• A recipient sees the model's structure and properties, but native material and classification cards that need the original file bytes are surfaced as plain property groups instead. Geometry, hierarchy, names, properties, classifications, and materials are all available.
• Per-peer role changes aren't supported — access comes from the link (issue a new link / revoke the old one instead). Admins can remove a peer.
• See also Privacy for the data-handling disclosure.

Running it yourself

• Try it locally (no server): enable the flag and open the viewer in two browser tabs — they sync through the browser. Geometry + presence work; this is the quickest way to see it.
• Multi-user across machines: stand up the collaboration server and point the viewer at it. That guide covers signed links, revoke/kick, and deployment.