SU.810b A live link from a .3dm modeller into ModelCraft and PartCraft (one way, a script on the other side)

Asked (#810, Oct 19): a live connection between Rhino models and our apps, perhaps through Grasshopper.

Built 2026-11-06, in /lab (log docs/0.9-sessions/3dm-link-09.md; design docs/spikes/SU.810.md). One script, cadcraft_link.py, runs in Rhino (watches the document, pushes after a pause, only what changed) and in a Grasshopper Script component (each solve). It sends .3dm bytes to Studio on this computer; link_push and link_status replace what the link brought last time: one group in ModelCraft (its placement, tag and neighbours stay; pushes within 2 s share an undo step), one import feature in PartCraft (features rebuild; a model that does not close changes nothing and says so). Over 4 MB goes in parts. The saved file keeps the link. Library lib/3dm-link, help live-3dm-link in both apps.

Tests: tools/3dm-link/test.mjs 31/0; browser.mjs 38/0 (the real script with rhino3dm's writer, through the reference server and hub relay, into real /lab pages).

Never run: real Rhino and real Grasshopper (none here; a stand-in plays their document and events, member names checked against McNeel's docs), Studio's native server, files saved by Rhino itself, SuperCad Studio's mounts. Not built: changes going back the other way, a packaged plug-in.