.dotl file format

Format version 1, document schema 1. File names typically look like ev-plani.dotl or raf-tasarimi.dotl.

Container

A .dotl file is a ZIP archive (stored or deflate entries):

manifest.json            format, formatVersion, producer, schemaVersion, plugins[], assets[]
document.json            the document (schema-versioned JSON)
view.json                optional view state (camera, panels) — never geometry
assets/<sha256>.<ext>    binary assets referenced from the document as "asset:<sha256>.<ext>"

manifest.json:

{
  "format": "dotloom",
  "formatVersion": 1,
  "schemaVersion": 1,
  "producer": { "name": "dotloom", "version": "1.0.0" },
  "plugins": [{ "typeId": "floorplan.wall", "version": 2 }],
  "assets": [{ "path": "assets/9f2c….png", "mediaType": "image/png", "size": 1234, "sha256": "9f2c…" }]
}

Writing is deterministic (same document → same bytes). Unknown ZIP entries and unknown JSON fields are preserved when a file is loaded and saved again.

document.json

{
  "schema": 1,
  "meta": { "title": "ev-plani" },
  "settings": { "displayUnit": "metre", "grid": { "spacing": 100, "majorEvery": 10 } },
  "layers": [{ "id": 1, "name": "Default" }],
  "entities": [
    { "id": 2, "type": "dotloom.line", "layer": 1, "geometry": { "type": "line", "a": [0, 0], "b": [4000, 0] } },
    { "id": 3, "type": "floorplan.door", "typeVersion": 1, "layer": 1, "props": { "host": { "ref": 2 }, "offset": 500, "width": 900 } }
  ],
  "groups": [],
  "constraints": [{ "id": 4, "rule": { "kind": "fix", "param": { "entity": 3, "prop": "width" }, "value": 900 }, "label": "door width" }],
  "nextId": 5
}

Coordinates are millimetres with Y up; angles radians; times seconds. Points are [x, y] arrays.

What is not stored

Renderer caches, WebAssembly state, solver iterations and the undo history are never written. Opening a file never runs code and never fetches anything.

Validation and limits

Readers verify, before anything is shown:

• ZIP: no absolute or .. paths, no duplicate names, UTF-8 names, at most 10 000 entries, 64 MiB per entry, 256 MiB in total, compression ratio ≤ 1024;
• JSON: nesting ≤ 128; up to 1 000 000 entities and constraints, 10 000 layers, 100 000 groups, 1 000 properties per entity, 100 000 characters per string;
• document invariants: unique IDs, valid references and anchors, no group cycles, finite numbers, asset hashes matching their content.

Migration

Older document schemas are migrated step by step with tests; a file from a newer major schema is rejected with a clear error (FutureSchema). Plugin types migrate their own instances (migrations in the type definition).

Missing plugins

Entities whose type is not registered keep their payload and are drawn from the stored fallback representation; they are read-only until the plugin is available. Their data is written back unchanged.

Clipboard and references

• Copied entities get new IDs; references between copied entities (properties, constraints, groups) are remapped to the new IDs.
• Constraints and groups are copied only when all their entities are copied.
• A property reference to an entity outside the copy is kept when that entity exists in the destination document (a pasted door keeps its host wall) and dropped otherwise; dropped references are reported.
• The paste offset is applied to entity transforms and to fixPoint targets.