DataModelParams (xeokit JSON) Loader / Exporter

DataModelImporter reads a DataModelParams JSON document into a DataModel, and DataModelExporter writes a DataModel back out as DataModelParams.

DataModelParams is the SDK's canonical JSON representation of a DataModel — the same param object accepted by Data.createModel and produced by DataModel.toParams. This module is the thin loader/exporter wrapper that plugs that representation into the common ModelLoader / ModelExporter pipeline, so it lives alongside the binary format adapters (FBX, RVM, XGF, …) and is driven the same way.

It is the semantic counterpart to the scenemodel format: where SceneModelParams carries the renderable half of a model (geometry, meshes, textures), DataModelParams carries the semantic half (objects, relationships, properties). The two pair naturally — a .json data sidecar alongside an .xgf geometry payload.

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1. The format

DataModelParams is a plain JSON object — no binary container, no geometry. It captures a DataModel's complete semantic state:

• id plus optional metadata — projectId, revisionId, author, createdAt, creatingApplication, schema.
• propertySets — named property sets, each a list of typed properties.
• objects — the DataObject graph (typed semantic entities).
• relationships — typed links between objects.

Because it mirrors the DataModel's own param surface, a round-trip is lossless: object ids, relationships, and properties survive export → import unchanged. That makes it useful as a cache payload, a test fixture, or a hand-inspectable debug dump.

The document carries an optional version field — the exporter stamps "1.0", and the loader keys its parser table on it, defaulting to "1.0" when absent.

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2. Load / export pipeline

Both sides are deliberately thin — the real work lives on DataModel:

   DataModelParams (JSON object)
        │
        ▼
   versions/1_0/parse.ts
        │   dataModel.fromParams(fileData)
        ▼
   DataModel populated


   DataModel
        │
        ▼
   versions/1_0/encode.ts
        │   dataModel.toParams()  →  DataModelParams  (+ version "1.0")
        ▼
   DataModelParams (JSON object)
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• Loader (DataModelImporter) — format: "DataModelParams", fileDataType: "json". getVersion reads fileData.version (falling back to "1.0") and dispatches to the matching parser. The "1.0" parser delegates straight to DataModel.fromParams.
• Exporter (DataModelExporter) — same format, same fileDataType, defaultVersion: "1.0". The "1.0" encoder calls DataModel.toParams, stamps version: "1.0", and resolves the resulting DataModelParams object. Encoding yields cooperatively to the host (yieldToHost) so a large model doesn't block the main thread.

fileData here is the parsed JSON object, not a string — read the .json with JSON.parse (or response.json()) before handing it to the loader, and JSON.stringify the exporter's result before persisting it.

Unlike a SceneModel, a DataModel has no build() step — it is ready to query as soon as load resolves.

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3. Usage

Loader

import {Data} from "@xeokit/sdk/model/data";
import {DataModelImporter} from "@xeokit/sdk/datamodel";

const data = new Data();
const dataModel = data.createModel({id: "myModel"}).value;

const fileData = await (await fetch("model.json")).json();

await new DataModelImporter().load({fileData, dataModel});
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Exporter

import {DataModelExporter} from "@xeokit/sdk/datamodel";

const dataModelParams = await new DataModelExporter().write({dataModel});
const json = JSON.stringify(dataModelParams);
// persist or transmit `json`
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The exporter resolves the DataModelParams object itself; stringify it yourself when you need bytes on disk or over the wire.

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4. File map

formats/datamodel/
├── README.md                 (this file)
├── DataModelImporter.ts      ModelLoader subclass — entry point
├── DataModelExporter.ts      ModelExporter subclass — write-side
├── index.ts                  module re-exports
└── versions/1_0/
    ├── parse.ts              fileData → DataModel.fromParams
    └── encode.ts             DataModel.toParams → DataModelParams
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