Method _cacheSegmentation

modules/services/MapillaryService.js:1256–1293

* _cacheSegmentation * Store the given segmentation in the caches * @param {Object} cache - the cache to use * @param {Object} props - the segmentation properties * @return {Object?} The segmentation data, or `null` if we are skipping it (see below)

(cache, props)

   * @return {Object?} The segmentation data, or `null` if we are skipping it (see below)
   */
  _cacheSegmentation(cache, props) {
    // Note: not all segmentations are ones we can work with.
    // For now, we'll only keep the ones that correspond to the known object detections and traffic_signs.
    const isDetection = this.getDetectionPresetID(props.value);
    const isTrafficSign = /^(regulatory|information|warning|complementary)/.test(props.value);
    if (!isDetection && !isTrafficSign) return null;

    let segmentation = cache.data.get(props.id);
    if (!segmentation) {
      // Convert encoded geometry into a polygon..
      const decodedGeometry = window.atob(props.geometry);
      let arr = new Uint8Array(decodedGeometry.length);
      for (let i = 0; i < decodedGeometry.length; i++) {
        arr[i] = decodedGeometry.charCodeAt(i);
      }
      const tile = new VectorTile(new Protobuf(arr.buffer));
      const layer = tile.layers['mpy-or'];
      const geometries = layer.feature(0).loadGeometry();
      const polygon = geometries
        .map(ring => ring.map(point => [point.x / layer.extent, point.y / layer.extent]));
      const geometry = new window.mapillary.PolygonGeometry(polygon[0]);

      segmentation = {
        id:        props.id,
        imageID:   props.imageID,
        geometry:  geometry,
        value:     props.value
      };

      cache.data.set(segmentation.id, segmentation);
    }

    // Update whatever additional props we were passed..
    if (props.created_at)   segmentation.created_at   = props.created_at;
    if (props.detectionID)  segmentation.detectionID  = props.detectionID;

    return segmentation;
  }


  /**