Method getTileInfo

src/openlayers/mapping/WebMap.js:1579–1629

* @private * @function WebMap.prototype.getTileInfo * @description 获取rest map的图层参数。 * @param {Object} layerInfo - 图层信息。 * @param {function} callback - 获得wmts图层参数执行的回调函数

(layerInfo, callback, mapInfo)

   * @param {function} callback - 获得wmts图层参数执行的回调函数
   */
  getTileInfo(layerInfo, callback, mapInfo) {
    let that = this;
    let options = {
      withCredentials: that.isCredentail(layerInfo.url, layerInfo.proxy),
      withoutFormatSuffix: true
    };
    let tempUrl = layerInfo.url;
    if (layerInfo.url.indexOf('?token=') > -1) {
      layerInfo.credential = { token: layerInfo.url.split('?token=')[1] };
      layerInfo.url = layerInfo.url.split('?token=')[0];
    }
    let url = this.handleJSONSuffix(tempUrl);
    return FetchRequest.get(that.getRequestUrl(url, layerInfo.proxy), null, options)
      .then(function (response) {
        return response.json();
      })
      .then(async function (result) {
        // layerInfo.projection = mapInfo.projection;
        // layerInfo.extent = [mapInfo.extent.leftBottom.x, mapInfo.extent.leftBottom.y, mapInfo.extent.rightTop.x, mapInfo.extent.rightTop.y];
        // 比例尺 单位
        if (result && result.code && result.code !== 200) {
          throw result;
        }
        if (result.visibleScales) {
          layerInfo.visibleScales = result.visibleScales;
          layerInfo.coordUnit = result.coordUnit;
        }
        layerInfo.maxZoom = result.maxZoom;
        layerInfo.maxZoom = result.minZoom;
        let token = layerInfo.credential ? layerInfo.credential.token : undefined;
        layerInfo.format = 'png';
        // china_dark为默认底图，还是用png出图
        if (
          that.tileFormat === 'webp' &&
          layerInfo.url !== 'https://maptiles.supermapol.com/iserver/services/map_China/rest/maps/China_Dark'
        ) {
          const isSupprtWebp = await that.isSupportWebp(layerInfo.url, token, layerInfo.proxy);
          layerInfo.format = isSupprtWebp ? 'webp' : 'png';
        }
        // 请求结果完成 继续添加图层
        if (mapInfo) {
          //todo 这个貌似没有用到，下次优化
          callback && callback(mapInfo, null, true, that);
        } else {
          callback && callback(layerInfo);
        }
      })
      .catch(function (error) {
        that.errorCallback && that.errorCallback(error, 'getTileInfo', that.map);
      });
  }
  /**
   * @private
   * @function WebMap.prototype.getWMTSUrl