cesium/Source/Scene/parseFeatureMetadata.js

CesiumJS is a JavaScript library for creating 3D globes and 2D maps in a web browser without a plugin.

import Check from "../Core/Check.js";
import defaultValue from "../Core/defaultValue.js";
import defined from "../Core/defined.js";
import FeatureTable from "./FeatureTable.js";
import FeatureTexture from "./FeatureTexture.js";
import FeatureMetadata from "./FeatureMetadata.js";
import MetadataTable from "./MetadataTable.js";

/**
 * Parse the <code>EXT_feature_metadata</code> glTF extension to create a
 * feature metadata object.
 *
 * @param {Object} options Object with the following properties:
 * @param {Object} options.extension The extension JSON object.
 * @param {MetadataSchema} options.schema The parsed schema.
 * @param {Object.<String, Uint8Array>} [options.bufferViews] An object mapping bufferView IDs to Uint8Array objects.
 * @param {Object.<String, Texture>} [options.textures] An object mapping texture IDs to {@link Texture} objects.
 * @return {FeatureMetadata} A feature metadata object
 * @private
 * @experimental This feature is using part of the 3D Tiles spec that is not final and is subject to change without Cesium's standard deprecation policy.
 */
export default function parseFeatureMetadata(options) {
  options = defaultValue(options, defaultValue.EMPTY_OBJECT);
  var extension = options.extension;

  // The calling code is responsible for loading the schema.
  // This keeps metadata parsing synchronous.
  var schema = options.schema;

  //>>includeStart('debug', pragmas.debug);
  Check.typeOf.object("options.extension", extension);
  Check.typeOf.object("options.schema", schema);
  //>>includeEnd('debug');

  var featureTables = {};
  if (defined(extension.featureTables)) {
    for (var featureTableId in extension.featureTables) {
      if (extension.featureTables.hasOwnProperty(featureTableId)) {
        var featureTable = extension.featureTables[featureTableId];
        var classDefinition = schema.classes[featureTable.class];

        var metadataTable = new MetadataTable({
          count: featureTable.count,
          properties: featureTable.properties,
          class: classDefinition,
          bufferViews: options.bufferViews,
        });

        featureTables[featureTableId] = new FeatureTable({
          count: featureTable.count,
          metadataTable: metadataTable,
          extras: featureTable.extras,
          extensions: featureTable.extensions,
        });
      }
    }
  }

  var featureTextures = {};
  if (defined(extension.featureTextures)) {
    for (var featureTextureId in extension.featureTextures) {
      if (extension.featureTextures.hasOwnProperty(featureTextureId)) {
        var featureTexture = extension.featureTextures[featureTextureId];
        featureTextures[featureTextureId] = new FeatureTexture({
          featureTexture: featureTexture,
          class: schema.classes[featureTexture.class],
          textures: options.textures,
        });
      }
    }
  }

  return new FeatureMetadata({
    schema: schema,
    featureTables: featureTables,
    featureTextures: featureTextures,
    statistics: extension.statistics,
    extras: extension.extras,
    extensions: extension.extensions,
  });
}