cesium 加载4490坐标系

1.修改 ArcGisMapServerImageryProvider.js 源码

读取切片元数据时增加支持 wkid 4490 坐标系的判断，同时将切片信息也传

if (data.fullExtent.spatialReference.wkid === 4490) {
  that._tilingScheme = new GeographicTilingScheme({
    ellipsoid: imageryProviderBuilder.ellipsoid,
    tileInfo: data.tileInfo, // 传入tileInfo，用于后面GeographicTilingScheme的计算
  });
  //SmartEarth 修改
}

fullExtent 范围增加 wkid 4490 坐标系判断

if (data.fullExtent.spatialReference.wkid === 4490) {
  /** Geoworld Add **/
  // SmartEarth 修改
  that._rectangle = Rectangle.fromDegrees(
    data.fullExtent.xmin,
    data.fullExtent.ymin,
    data.fullExtent.xmax,
    data.fullExtent.ymax
  );
  // SmartEarth 修改
}

function metadataSuccess(data, imageryProviderBuilder) {
  const tileInfo = data.tileInfo;
  if (!defined(tileInfo)) {
    imageryProviderBuilder.useTiles = false;
  } else {
    imageryProviderBuilder.tileWidth = tileInfo.rows;
    imageryProviderBuilder.tileHeight = tileInfo.cols;

    if (tileInfo.spatialReference.wkid === 102100 || tileInfo.spatialReference.wkid === 102113) {
      imageryProviderBuilder.tilingScheme = new WebMercatorTilingScheme({
        ellipsoid: imageryProviderBuilder.ellipsoid,
      });
    } else if (data.tileInfo.spatialReference.wkid === 4326) {
      imageryProviderBuilder.tilingScheme = new GeographicTilingScheme({
        ellipsoid: imageryProviderBuilder.ellipsoid,
      });
      /** Geoworld **/
      //SmartEarth 修改
    } else if (data.fullExtent.spatialReference.wkid === 4490) {
      that._tilingScheme = new GeographicTilingScheme({
        ellipsoid: imageryProviderBuilder.ellipsoid,
        tileInfo: data.tileInfo, // 传入tileInfo，用于后面GeographicTilingScheme的计算
      });
      //SmartEarth 修改
    } else {
      const message = `Tile spatial reference WKID ${data.tileInfo.spatialReference.wkid} is not supported.`;
      throw new RuntimeError(message);
    }
    imageryProviderBuilder.maximumLevel = data.tileInfo.lods.length - 1;

    if (defined(data.fullExtent)) {
      if (
        defined(data.fullExtent.spatialReference) &&
        defined(data.fullExtent.spatialReference.wkid)
      ) {
        if (
          data.fullExtent.spatialReference.wkid === 102100 ||
          data.fullExtent.spatialReference.wkid === 102113
        ) {
          const projection = new WebMercatorProjection();
          const extent = data.fullExtent;
          const sw = projection.unproject(
            new Cartesian3(
              Math.max(
                extent.xmin,
                -imageryProviderBuilder.tilingScheme.ellipsoid.maximumRadius * Math.PI
              ),
              Math.max(
                extent.ymin,
                -imageryProviderBuilder.tilingScheme.ellipsoid.maximumRadius * Math.PI
              ),
              0.0
            )
          );
          const ne = projection.unproject(
            new Cartesian3(
              Math.min(
                extent.xmax,
                imageryProviderBuilder.tilingScheme.ellipsoid.maximumRadius * Math.PI
              ),
              Math.min(
                extent.ymax,
                imageryProviderBuilder.tilingScheme.ellipsoid.maximumRadius * Math.PI
              ),
              0.0
            )
          );
          imageryProviderBuilder.rectangle = new Rectangle(
            sw.longitude,
            sw.latitude,
            ne.longitude,
            ne.latitude
          );
        } else if (data.fullExtent.spatialReference.wkid === 4326) {
          imageryProviderBuilder.rectangle = Rectangle.fromDegrees(
            data.fullExtent.xmin,
            data.fullExtent.ymin,
            data.fullExtent.xmax,
            data.fullExtent.ymax
          );
        } else if (data.fullExtent.spatialReference.wkid === 4490) {
          /** Geoworld Add **/
          // SmartEarth 修改
          that._rectangle = Rectangle.fromDegrees(
            data.fullExtent.xmin,
            data.fullExtent.ymin,
            data.fullExtent.xmax,
            data.fullExtent.ymax
          );
          // SmartEarth 修改
        } else {
          const extentMessage = `fullExtent.spatialReference WKID ${data.fullExtent.spatialReference.wkid} is not supported.`;
          throw new RuntimeError(extentMessage);
        }
      }
    } else {
      imageryProviderBuilder.rectangle = imageryProviderBuilder.tilingScheme.rectangle;
    }

    imageryProviderBuilder.useTiles = true;
  }

  if (defined(data.copyrightText) && data.copyrightText.length > 0) {
    if (defined(imageryProviderBuilder.credit)) {
      imageryProviderBuilder.tileCredits = [new Credit(data.copyrightText)];
    } else {
      imageryProviderBuilder.credit = new Credit(data.copyrightText);
    }
  }
}

2.修改 GeographicTilingScheme 类

/** Geoworld Add **/
//SmartEarth 修改
this._tileInfo = options.tileInfo;
//SmartEarth 修改

修改切片矩阵计算获取行列号 xy 值的原型方法 getNumberOfXTilesAtLevel 和 getNumberOfYTilesAtLevel

GeographicTilingScheme.prototype.getNumberOfXTilesAtLevel = function (level) {
  // return this._numberOfLevelZeroTilesX << level;
  /** Geoworld Add **/
  //SmartEarth 修改
  if (!defined(this._tileInfo)) {
    return this._numberOfLevelZeroTilesX << level;
  }
  const currentMatrix = this._tileInfo.lods.filter(function (item) {
    return item.level === level;
  });
  const currentResolution = currentMatrix[0].resolution;
  return Math.round(360 / (this._tileInfo.rows * currentResolution));
  //SmartEarth 修改
};

/**
 * Gets the total number of tiles in the Y direction at a specified level-of-detail.
 *
 * @param {number} level The level-of-detail.
 * @returns {number} The number of tiles in the Y direction at the given level.
 */
GeographicTilingScheme.prototype.getNumberOfYTilesAtLevel = function (level) {
  // return this._numberOfLevelZeroTilesY << level;
  //SmartEarth 修改
  if (!defined(this._tileInfo)) {
    return this._numberOfLevelZeroTilesY << level;
  }
  // 使用切片矩阵计算
  const currentMatrix = this._tileInfo.lods.filter(function (item) {
    return item.level === level;
  });
  const currentResolution = currentMatrix[0].resolution;
  return Math.round(180 / (this._tileInfo.cols * currentResolution));
  //SmartEarth 修改
};

3.修改 Ellipsoid 类，定义 2000 椭球参数

/**
 * An Ellipsoid instance initialized to the CGCS2000 standard.
 *
 * @type {Ellipsoid}
 * @constant
 */
/** Geoworld Add **/
Ellipsoid.CGCS2000 = Object.freeze(
  // eslint-disable-next-line no-loss-of-precision
  new Ellipsoid(6378137.0, 6378137.0, 6356752.31414035585)
);

使用

var cgs2000Ellipsolid = new Cesium.Ellipsoid(6378137.0, 6378137.0, 6356752.31414035585);
var myGeographicTilingScheme = new Cesium.GeographicTilingScheme({
  ellipsoid: cgs2000Ellipsolid,
  rectangle: Cesium.Rectangle.fromDegrees(-180, -90, 180, 90),
  numberOfLevelZeroTilesX: 4,
  numberOfLevelZeroTilesY: 2,
});
var esriWMTS = new Cesium.ArcGisMapServerImageryProvider({
  url: "http://Ip:6080/arcgis/rest/services/jssl_vector_L3_L17/MapServer",
  layer: "jssl_vector_L3_L17",
  tilingScheme: myGeographicTilingScheme,
  rectangle: myRectangle,
  minimumLevel: 0,
  ellipsoid: cgs2000Ellipsolid,
  maximumLevel: 14,
});

var cgs2000GeographicProj = new Cesium.GeographicProjection(cgs2000Ellipsolid);
var viewer = new Cesium.Viewer("cesiumContainer", {
  animation: false,
  geocoder: false,
  timeline: false,
  navigationHelpButton: false,
  baseLayerPicker: false,
  mapProjection: cgs2000GeographicProj,
  imageryProvider: esriWMTS,
});
viewer.camera.flyTo({
  destination: Cesium.Cartesian3.fromDegrees(119.56156642831284, 32.419457329767326, 272683),
});