Persistence

Timeline: Feb 5, 2026 | Status: done

Save/load scene state.

Goals

JSON Serialize
- SO state (bounds)
- SO orientation (moved from O_Scene to Smart_Object as SOT)
- camera position (eye, center, up)
Save to localStorage (single scene, auto-save on drag)
Load latest one on app start
Clear/reset option (reset button in Controls, white bg, black hover)

Format Research

Format	Speed	Size	Human Readable	Notes
JSON	Baseline	Largest	Yes	Universal, easy debugging
MessagePack	~37% faster	~15% smaller	No	Best performance overall
CBOR	~27% faster	~27% smaller	No	AWS-friendly, JSON-like schema
BSON	Slower encode, faster decode	Larger than MP	No	MongoDB native

Key findings:

MessagePack wins on raw performance — 10K objects serialize in ~918μs
CBOR is the best drop-in JSON replacement (same data model, binary encoding)
JSON still solid for debugging and human editing

Decision: Use JSON — readable, debuggable, localStorage-friendly. If performance becomes an issue, use MessagePack or CBOR (same structure, just binary).

Sources:

Implementation

Smart_Object.serialize() / Smart_Object.deserialize() — name + 6 bounds + orientation quat
Camera.serialize() / Camera.deserialize() — eye, center, up vectors
Scenes manager — save/load/clear via Preferences localStorage wrapper
Setup.ts — loads saved state on init, saves after every drag

Notes