cesium_nxmap/_cesium@1.72.0@cesium/Source/Core/GoogleEarthEnterpriseMetadata.js

import protobufMinimal from "../ThirdParty/protobuf-minimal.js";
import when from "../ThirdParty/when.js";
import buildModuleUrl from "./buildModuleUrl.js";
import Check from "./Check.js";
import Credit from "./Credit.js";
import defaultValue from "./defaultValue.js";
import defined from "./defined.js";
import GoogleEarthEnterpriseTileInformation from "./GoogleEarthEnterpriseTileInformation.js";
import isBitSet from "./isBitSet.js";
import loadAndExecuteScript from "./loadAndExecuteScript.js";
import CesiumMath from "./Math.js";
import Request from "./Request.js";
import Resource from "./Resource.js";
import RuntimeError from "./RuntimeError.js";
import TaskProcessor from "./TaskProcessor.js";

function stringToBuffer(str) {
  var len = str.length;
  var buffer = new ArrayBuffer(len);
  var ui8 = new Uint8Array(buffer);
  for (var i = 0; i < len; ++i) {
    ui8[i] = str.charCodeAt(i);
  }

  return buffer;
}

// Decodes packet with a key that has been around since the beginning of Google Earth Enterprise
var defaultKey = stringToBuffer(
  "\x45\xf4\xbd\x0b\x79\xe2\x6a\x45\x22\x05\x92\x2c\x17\xcd\x06\x71\xf8\x49\x10\x46\x67\x51\x00\x42\x25\xc6\xe8\x61\x2c\x66\x29\x08\xc6\x34\xdc\x6a\x62\x25\x79\x0a\x77\x1d\x6d\x69\xd6\xf0\x9c\x6b\x93\xa1\xbd\x4e\x75\xe0\x41\x04\x5b\xdf\x40\x56\x0c\xd9\xbb\x72\x9b\x81\x7c\x10\x33\x53\xee\x4f\x6c\xd4\x71\x05\xb0\x7b\xc0\x7f\x45\x03\x56\x5a\xad\x77\x55\x65\x0b\x33\x92\x2a\xac\x19\x6c\x35\x14\xc5\x1d\x30\x73\xf8\x33\x3e\x6d\x46\x38\x4a\xb4\xdd\xf0\x2e\xdd\x17\x75\x16\xda\x8c\x44\x74\x22\x06\xfa\x61\x22\x0c\x33\x22\x53\x6f\xaf\x39\x44\x0b\x8c\x0e\x39\xd9\x39\x13\x4c\xb9\xbf\x7f\xab\x5c\x8c\x50\x5f\x9f\x22\x75\x78\x1f\xe9\x07\x71\x91\x68\x3b\xc1\xc4\x9b\x7f\xf0\x3c\x56\x71\x48\x82\x05\x27\x55\x66\x59\x4e\x65\x1d\x98\x75\xa3\x61\x46\x7d\x61\x3f\x15\x41\x00\x9f\x14\x06\xd7\xb4\x34\x4d\xce\x13\x87\x46\xb0\x1a\xd5\x05\x1c\xb8\x8a\x27\x7b\x8b\xdc\x2b\xbb\x4d\x67\x30\xc8\xd1\xf6\x5c\x8f\x50\xfa\x5b\x2f\x46\x9b\x6e\x35\x18\x2f\x27\x43\x2e\xeb\x0a\x0c\x5e\x10\x05\x10\xa5\x73\x1b\x65\x34\xe5\x6c\x2e\x6a\x43\x27\x63\x14\x23\x55\xa9\x3f\x71\x7b\x67\x43\x7d\x3a\xaf\xcd\xe2\x54\x55\x9c\xfd\x4b\xc6\xe2\x9f\x2f\x28\xed\xcb\x5c\xc6\x2d\x66\x07\x88\xa7\x3b\x2f\x18\x2a\x22\x4e\x0e\xb0\x6b\x2e\xdd\x0d\x95\x7d\x7d\x47\xba\x43\xb2\x11\xb2\x2b\x3e\x4d\xaa\x3e\x7d\xe6\xce\x49\x89\xc6\xe6\x78\x0c\x61\x31\x05\x2d\x01\xa4\x4f\xa5\x7e\x71\x20\x88\xec\x0d\x31\xe8\x4e\x0b\x00\x6e\x50\x68\x7d\x17\x3d\x08\x0d\x17\x95\xa6\x6e\xa3\x68\x97\x24\x5b\x6b\xf3\x17\x23\xf3\xb6\x73\xb3\x0d\x0b\x40\xc0\x9f\xd8\x04\x51\x5d\xfa\x1a\x17\x22\x2e\x15\x6a\xdf\x49\x00\xb9\xa0\x77\x55\xc6\xef\x10\x6a\xbf\x7b\x47\x4c\x7f\x83\x17\x05\xee\xdc\xdc\x46\x85\xa9\xad\x53\x07\x2b\x53\x34\x06\x07\xff\x14\x94\x59\x19\x02\xe4\x38\xe8\x31\x83\x4e\xb9\x58\x46\x6b\xcb\x2d\x23\x86\x92\x70\x00\x35\x88\x22\xcf\x31\xb2\x26\x2f\xe7\xc3\x75\x2d\x36\x2c\x72\x74\xb0\x23\x47\xb7\xd3\xd1\x26\x16\x85\x37\x72\xe2\x00\x8c\x44\xcf\x10\xda\x33\x2d\x1a\xde\x60\x86\x69\x23\x69\x2a\x7c\xcd\x4b\x51\x0d\x95\x54\x39\x77\x2e\x29\xea\x1b\xa6\x50\xa2\x6a\x8f\x6f\x50\x99\x5c\x3e\x54\xfb\xef\x50\x5b\x0b\x07\x45\x17\x89\x6d\x28\x13\x77\x37\x1d\xdb\x8e\x1e\x4a\x05\x66\x4a\x6f\x99\x20\xe5\x70\xe2\xb9\x71\x7e\x0c\x6d\x49\x04\x2d\x7a\xfe\x72\xc7\xf2\x59\x30\x8f\xbb\x02\x5d\x73\xe5\xc9\x20\xea\x78\xec\x20\x90\xf0\x8a\x7f\x42\x17\x7c\x47\x19\x60\xb0\x16\xbd\x26\xb7\x71\xb6\xc7\x9f\x0e\xd1\x33\x82\x3d\xd3\xab\xee\x63\x99\xc8\x2b\x53\xa0\x44\x5c\x71\x01\xc6\xcc\x44\x1f\x32\x4f\x3c\xca\xc0\x29\x3d\x52\xd3\x61\x19\x58\xa9\x7d\x65\xb4\xdc\xcf\x0d\xf4\x3d\xf1\x08\xa9\x42\xda\x23\x09\xd8\xbf\x5e\x50\x49\xf8\x4d\xc0\xcb\x47\x4c\x1c\x4f\xf7\x7b\x2b\xd8\x16\x18\xc5\x31\x92\x3b\xb5\x6f\xdc\x6c\x0d\x92\x88\x16\xd1\x9e\xdb\x3f\xe2\xe9\xda\x5f\xd4\x84\xe2\x46\x61\x5a\xde\x1c\x55\xcf\xa4\x00\xbe\xfd\xce\x67\xf1\x4a\x69\x1c\x97\xe6\x20\x48\xd8\x5d\x7f\x7e\xae\x71\x20\x0e\x4e\xae\xc0\x56\xa9\x91\x01\x3c\x82\x1d\x0f\x72\xe7\x76\xec\x29\x49\xd6\x5d\x2d\x83\xe3\xdb\x36\x06\xa9\x3b\x66\x13\x97\x87\x6a\xd5\xb6\x3d\x50\x5e\x52\xb9\x4b\xc7\x73\x57\x78\xc9\xf4\x2e\x59\x07\x95\x93\x6f\xd0\x4b\x17\x57\x19\x3e\x27\x27\xc7\x60\xdb\x3b\xed\x9a\x0e\x53\x44\x16\x3e\x3f\x8d\x92\x6d\x77\xa2\x0a\xeb\x3f\x52\xa8\xc6\x55\x5e\x31\x49\x37\x85\xf4\xc5\x1f\x26\x2d\xa9\x1c\xbf\x8b\x27\x54\xda\xc3\x6a\x20\xe5\x2a\x78\x04\xb0\xd6\x90\x70\x72\xaa\x8b\x68\xbd\x88\xf7\x02\x5f\x48\xb1\x7e\xc0\x58\x4c\x3f\x66\x1a\xf9\x3e\xe1\x65\xc0\x70\xa7\xcf\x38\x69\xaf\xf0\x56\x6c\x64\x49\x9c\x27\xad\x78\x74\x4f\xc2\x87\xde\x56\x39\x00\xda\x77\x0b\xcb\x2d\x1b\x89\xfb\x35\x4f\x02\xf5\x08\x51\x13\x60\xc1\x0a\x5a\x47\x4d\x26\x1c\x33\x30\x78\xda\xc0\x9c\x46\x47\xe2\x5b\x79\x60\x49\x6e\x37\x67\x53\x0a\x3e\xe9\xec\x46\x39\xb2\xf1\x34\x0d\xc6\x84\x53\x75\x6e\xe1\x0c\x59\xd9\x1e\xde\x29\x85\x10\x7b\x49\x49\xa5\x77\x79\xbe\x49\x56\x2e\x36\xe7\x0b\x3a\xbb\x4f\x03\x62\x7b\xd2\x4d\x31\x95\x2f\xbd\x38\x7b\xa8\x4f\x21\xe1\xec\x46\x70\x76\x95\x7d\x29\x22\x78\x88\x0a\x90\xdd\x9d\x5c\xda\xde\x19\x51\xcf\xf0\xfc\x59\x52\x65\x7c\x33\x13\xdf\xf3\x48\xda\xbb\x2a\x75\xdb\x60\xb2\x02\x15\xd4\xfc\x19\xed\x1b\xec\x7f\x35\xa8\xff\x28\x31\x07\x2d\x12\xc8\xdc\x88\x46\x7c\x8a\x5b\x22"
);

/**
 * Provides metadata using the Google Earth Enterprise REST API. This is used by the GoogleEarthEnterpriseImageryProvider
 *  and GoogleEarthEnterpriseTerrainProvider to share metadata requests.
 *
 * @alias GoogleEarthEnterpriseMetadata
 * @constructor
 *
 * @param {Resource|String} resourceOrUrl The url of the Google Earth Enterprise server hosting the imagery
 *
 * @see GoogleEarthEnterpriseImageryProvider
 * @see GoogleEarthEnterpriseTerrainProvider
 *
 */
function GoogleEarthEnterpriseMetadata(resourceOrUrl) {
  //>>includeStart('debug', pragmas.debug);
  Check.defined("resourceOrUrl", resourceOrUrl);
  //>>includeEnd('debug');

  var url = resourceOrUrl;

  if (typeof url !== "string" && !(url instanceof Resource)) {
    //>>includeStart('debug', pragmas.debug);
    Check.typeOf.string("resourceOrUrl.url", resourceOrUrl.url);
    //>>includeEnd('debug');

    url = resourceOrUrl.url;
  }

  var resource = Resource.createIfNeeded(url);
  resource.appendForwardSlash();
  this._resource = resource;

  /**
   * True if imagery is available.
   * @type {Boolean}
   * @default true
   */
  this.imageryPresent = true;

  /**
   * True if imagery is sent as a protocol buffer, false if sent as plain images. If undefined we will try both.
   * @type {Boolean}
   * @default undefined
   */
  this.protoImagery = undefined;

  /**
   * True if terrain is available.
   * @type {Boolean}
   * @default true
   */
  this.terrainPresent = true;

  /**
   * Exponent used to compute constant to calculate negative height values.
   * @type {Number}
   * @default 32
   */
  this.negativeAltitudeExponentBias = 32;

  /**
   * Threshold where any numbers smaller are actually negative values. They are multiplied by -2^negativeAltitudeExponentBias.
   * @type {Number}
   * @default EPSILON12
   */
  this.negativeAltitudeThreshold = CesiumMath.EPSILON12;

  /**
   * Dictionary of provider id to copyright strings.
   * @type {Object}
   * @default {}
   */
  this.providers = {};

  /**
   * Key used to decode packets
   * @type {ArrayBuffer}
   */
  this.key = undefined;

  this._quadPacketVersion = 1;

  this._tileInfo = {};
  this._subtreePromises = {};

  var that = this;
  this._readyPromise = requestDbRoot(this)
    .then(function () {
      return that.getQuadTreePacket("", that._quadPacketVersion);
    })
    .then(function () {
      return true;
    })
    .otherwise(function (e) {
      var message =
        "An error occurred while accessing " +
        getMetadataResource(that, "", 1).url +
        ".";
      return when.reject(new RuntimeError(message));
    });
}

Object.defineProperties(GoogleEarthEnterpriseMetadata.prototype, {
  /**
   * Gets the name of the Google Earth Enterprise server.
   * @memberof GoogleEarthEnterpriseMetadata.prototype
   * @type {String}
   * @readonly
   */
  url: {
    get: function () {
      return this._resource.url;
    },
  },

  /**
   * Gets the proxy used for metadata requests.
   * @memberof GoogleEarthEnterpriseMetadata.prototype
   * @type {Proxy}
   * @readonly
   */
  proxy: {
    get: function () {
      return this._resource.proxy;
    },
  },

  /**
   * Gets the resource used for metadata requests.
   * @memberof GoogleEarthEnterpriseMetadata.prototype
   * @type {Resource}
   * @readonly
   */
  resource: {
    get: function () {
      return this._resource;
    },
  },

  /**
   * Gets a promise that resolves to true when the metadata is ready for use.
   * @memberof GoogleEarthEnterpriseMetadata.prototype
   * @type {Promise.<Boolean>}
   * @readonly
   */
  readyPromise: {
    get: function () {
      return this._readyPromise;
    },
  },
});

/**
 * Converts a tiles (x, y, level) position into a quadkey used to request an image
 * from a Google Earth Enterprise server.
 *
 * @param {Number} x The tile's x coordinate.
 * @param {Number} y The tile's y coordinate.
 * @param {Number} level The tile's zoom level.
 *
 * @see GoogleEarthEnterpriseMetadata#quadKeyToTileXY
 */
GoogleEarthEnterpriseMetadata.tileXYToQuadKey = function (x, y, level) {
  var quadkey = "";
  for (var i = level; i >= 0; --i) {
    var bitmask = 1 << i;
    var digit = 0;

    // Tile Layout
    // ___ ___
    //|   |   |
    //| 3 | 2 |
    //|-------|
    //| 0 | 1 |
    //|___|___|
    //

    if (!isBitSet(y, bitmask)) {
      // Top Row
      digit |= 2;
      if (!isBitSet(x, bitmask)) {
        // Right to left
        digit |= 1;
      }
    } else if (isBitSet(x, bitmask)) {
      // Left to right
      digit |= 1;
    }

    quadkey += digit;
  }
  return quadkey;
};

/**
 * Converts a tile's quadkey used to request an image from a Google Earth Enterprise server into the
 * (x, y, level) position.
 *
 * @param {String} quadkey The tile's quad key
 *
 * @see GoogleEarthEnterpriseMetadata#tileXYToQuadKey
 */
GoogleEarthEnterpriseMetadata.quadKeyToTileXY = function (quadkey) {
  var x = 0;
  var y = 0;
  var level = quadkey.length - 1;
  for (var i = level; i >= 0; --i) {
    var bitmask = 1 << i;
    var digit = +quadkey[level - i];

    if (isBitSet(digit, 2)) {
      // Top Row
      if (!isBitSet(digit, 1)) {
        // // Right to left
        x |= bitmask;
      }
    } else {
      y |= bitmask;
      if (isBitSet(digit, 1)) {
        // Left to right
        x |= bitmask;
      }
    }
  }
  return {
    x: x,
    y: y,
    level: level,
  };
};

GoogleEarthEnterpriseMetadata.prototype.isValid = function (quadKey) {
  var info = this.getTileInformationFromQuadKey(quadKey);
  if (defined(info)) {
    return info !== null;
  }

  var valid = true;
  var q = quadKey;
  var last;
  while (q.length > 1) {
    last = q.substring(q.length - 1);
    q = q.substring(0, q.length - 1);
    info = this.getTileInformationFromQuadKey(q);
    if (defined(info)) {
      if (!info.hasSubtree() && !info.hasChild(parseInt(last))) {
        // We have no subtree or child available at some point in this node's ancestry
        valid = false;
      }

      break;
    } else if (info === null) {
      // Some node in the ancestry was loaded and said there wasn't a subtree
      valid = false;
      break;
    }
  }

  return valid;
};

var taskProcessor = new TaskProcessor(
  "decodeGoogleEarthEnterprisePacket",
  Number.POSITIVE_INFINITY
);

/**
 * Retrieves a Google Earth Enterprise quadtree packet.
 *
 * @param {String} [quadKey=''] The quadkey to retrieve the packet for.
 * @param {Number} [version=1] The cnode version to be used in the request.
 * @param {Request} [request] The request object. Intended for internal use only.
 *
 * @private
 */
GoogleEarthEnterpriseMetadata.prototype.getQuadTreePacket = function (
  quadKey,
  version,
  request
) {
  version = defaultValue(version, 1);
  quadKey = defaultValue(quadKey, "");
  var resource = getMetadataResource(this, quadKey, version, request);

  var promise = resource.fetchArrayBuffer();

  if (!defined(promise)) {
    return undefined; // Throttled
  }

  var tileInfo = this._tileInfo;
  var key = this.key;
  return promise.then(function (metadata) {
    var decodePromise = taskProcessor.scheduleTask(
      {
        buffer: metadata,
        quadKey: quadKey,
        type: "Metadata",
        key: key,
      },
      [metadata]
    );

    return decodePromise.then(function (result) {
      var root;
      var topLevelKeyLength = -1;
      if (quadKey !== "") {
        // Root tile has no data except children bits, so put them into the tile info
        topLevelKeyLength = quadKey.length + 1;
        var top = result[quadKey];
        root = tileInfo[quadKey];
        root._bits |= top._bits;

        delete result[quadKey];
      }

      // Copy the resulting objects into tileInfo
      // Make sure we start with shorter quadkeys first, so we know the parents have
      //  already been processed. Otherwise we can lose ancestorHasTerrain along the way.
      var keys = Object.keys(result);
      keys.sort(function (a, b) {
        return a.length - b.length;
      });
      var keysLength = keys.length;
      for (var i = 0; i < keysLength; ++i) {
        var key = keys[i];
        var r = result[key];
        if (r !== null) {
          var info = GoogleEarthEnterpriseTileInformation.clone(result[key]);
          var keyLength = key.length;
          if (keyLength === topLevelKeyLength) {
            info.setParent(root);
          } else if (keyLength > 1) {
            var parent = tileInfo[key.substring(0, key.length - 1)];
            info.setParent(parent);
          }
          tileInfo[key] = info;
        } else {
          tileInfo[key] = null;
        }
      }
    });
  });
};

/**
 * Populates the metadata subtree down to the specified tile.
 *
 * @param {Number} x The tile X coordinate.
 * @param {Number} y The tile Y coordinate.
 * @param {Number} level The tile level.
 * @param {Request} [request] The request object. Intended for internal use only.
 *
 * @returns {Promise<GoogleEarthEnterpriseTileInformation>} A promise that resolves to the tile info for the requested quad key
 *
 * @private
 */
GoogleEarthEnterpriseMetadata.prototype.populateSubtree = function (
  x,
  y,
  level,
  request
) {
  var quadkey = GoogleEarthEnterpriseMetadata.tileXYToQuadKey(x, y, level);
  return populateSubtree(this, quadkey, request);
};

function populateSubtree(that, quadKey, request) {
  var tileInfo = that._tileInfo;
  var q = quadKey;
  var t = tileInfo[q];
  // If we have tileInfo make sure sure it is not a node with a subtree that's not loaded
  if (defined(t) && (!t.hasSubtree() || t.hasChildren())) {
    return t;
  }

  while (t === undefined && q.length > 1) {
    q = q.substring(0, q.length - 1);
    t = tileInfo[q];
  }

  var subtreeRequest;
  var subtreePromises = that._subtreePromises;
  var promise = subtreePromises[q];
  if (defined(promise)) {
    return promise.then(function () {
      // Recursively call this in case we need multiple subtree requests
      subtreeRequest = new Request({
        throttle: request.throttle,
        throttleByServer: request.throttleByServer,
        type: request.type,
        priorityFunction: request.priorityFunction,
      });
      return populateSubtree(that, quadKey, subtreeRequest);
    });
  }

  // t is either
  //   null so one of its parents was a leaf node, so this tile doesn't exist
  //   exists but doesn't have a subtree to request
  //   undefined so no parent exists - this shouldn't ever happen once the provider is ready
  if (!defined(t) || !t.hasSubtree()) {
    return when.reject(
      new RuntimeError("Couldn't load metadata for tile " + quadKey)
    );
  }

  // We need to split up the promise here because when will execute syncronously if getQuadTreePacket
  //  is already resolved (like in the tests), so subtreePromises will never get cleared out.
  //  Only the initial request will also remove the promise from subtreePromises.
  promise = that.getQuadTreePacket(q, t.cnodeVersion, request);
  if (!defined(promise)) {
    return undefined;
  }
  subtreePromises[q] = promise;

  return promise
    .then(function () {
      // Recursively call this in case we need multiple subtree requests
      subtreeRequest = new Request({
        throttle: request.throttle,
        throttleByServer: request.throttleByServer,
        type: request.type,
        priorityFunction: request.priorityFunction,
      });
      return populateSubtree(that, quadKey, subtreeRequest);
    })
    .always(function () {
      delete subtreePromises[q];
    });
}

/**
 * Gets information about a tile
 *
 * @param {Number} x The tile X coordinate.
 * @param {Number} y The tile Y coordinate.
 * @param {Number} level The tile level.
 * @returns {GoogleEarthEnterpriseTileInformation|undefined} Information about the tile or undefined if it isn't loaded.
 *
 * @private
 */
GoogleEarthEnterpriseMetadata.prototype.getTileInformation = function (
  x,
  y,
  level
) {
  var quadkey = GoogleEarthEnterpriseMetadata.tileXYToQuadKey(x, y, level);
  return this._tileInfo[quadkey];
};

/**
 * Gets information about a tile from a quadKey
 *
 * @param {String} quadkey The quadkey for the tile
 * @returns {GoogleEarthEnterpriseTileInformation|undefined} Information about the tile or undefined if it isn't loaded.
 *
 * @private
 */
GoogleEarthEnterpriseMetadata.prototype.getTileInformationFromQuadKey = function (
  quadkey
) {
  return this._tileInfo[quadkey];
};

function getMetadataResource(that, quadKey, version, request) {
  return that._resource.getDerivedResource({
    url: "flatfile?q2-0" + quadKey + "-q." + version.toString(),
    request: request,
  });
}

var dbrootParser;
var dbrootParserPromise;
function requestDbRoot(that) {
  var resource = that._resource.getDerivedResource({
    url: "dbRoot.v5",
    queryParameters: {
      output: "proto",
    },
  });

  if (!defined(dbrootParserPromise)) {
    var url = buildModuleUrl("ThirdParty/google-earth-dbroot-parser.js");
    var oldValue = window.cesiumGoogleEarthDbRootParser;
    dbrootParserPromise = loadAndExecuteScript(url).then(function () {
      dbrootParser = window.cesiumGoogleEarthDbRootParser(protobufMinimal);
      if (defined(oldValue)) {
        window.cesiumGoogleEarthDbRootParser = oldValue;
      } else {
        delete window.cesiumGoogleEarthDbRootParser;
      }
    });
  }

  return dbrootParserPromise
    .then(function () {
      return resource.fetchArrayBuffer();
    })
    .then(function (buf) {
      var encryptedDbRootProto = dbrootParser.EncryptedDbRootProto.decode(
        new Uint8Array(buf)
      );

      var byteArray = encryptedDbRootProto.encryptionData;
      var offset = byteArray.byteOffset;
      var end = offset + byteArray.byteLength;
      var key = (that.key = byteArray.buffer.slice(offset, end));

      byteArray = encryptedDbRootProto.dbrootData;
      offset = byteArray.byteOffset;
      end = offset + byteArray.byteLength;
      var dbRootCompressed = byteArray.buffer.slice(offset, end);
      return taskProcessor.scheduleTask(
        {
          buffer: dbRootCompressed,
          type: "DbRoot",
          key: key,
        },
        [dbRootCompressed]
      );
    })
    .then(function (result) {
      var dbRoot = dbrootParser.DbRootProto.decode(
        new Uint8Array(result.buffer)
      );
      that.imageryPresent = defaultValue(
        dbRoot.imageryPresent,
        that.imageryPresent
      );
      that.protoImagery = dbRoot.protoImagery;
      that.terrainPresent = defaultValue(
        dbRoot.terrainPresent,
        that.terrainPresent
      );
      if (defined(dbRoot.endSnippet) && defined(dbRoot.endSnippet.model)) {
        var model = dbRoot.endSnippet.model;
        that.negativeAltitudeExponentBias = defaultValue(
          model.negativeAltitudeExponentBias,
          that.negativeAltitudeExponentBias
        );
        that.negativeAltitudeThreshold = defaultValue(
          model.compressedNegativeAltitudeThreshold,
          that.negativeAltitudeThreshold
        );
      }
      if (defined(dbRoot.databaseVersion)) {
        that._quadPacketVersion = defaultValue(
          dbRoot.databaseVersion.quadtreeVersion,
          that._quadPacketVersion
        );
      }
      var providers = that.providers;
      var providerInfo = defaultValue(dbRoot.providerInfo, []);
      var count = providerInfo.length;
      for (var i = 0; i < count; ++i) {
        var provider = providerInfo[i];
        var copyrightString = provider.copyrightString;
        if (defined(copyrightString)) {
          providers[provider.providerId] = new Credit(copyrightString.value);
        }
      }
    })
    .otherwise(function () {
      // Just eat the error and use the default values.
      console.log("Failed to retrieve " + resource.url + ". Using defaults.");
      that.key = defaultKey;
    });
}
export default GoogleEarthEnterpriseMetadata;