cesium加载百度底图的方法源码

封装百度的js

function BaiduImageryProvider(options) {
    this._errorEvent = new Cesium.Event();
    this._tileWidth = 256;
    this._tileHeight = 256;
    this._maximumLevel = 18;
    this._minimumLevel = 1;
    var southwestInMeters = new Cesium.Cartesian2(-33554054, -33746824);
    var northeastInMeters = new Cesium.Cartesian2(33554054, 33746824);
    this._tilingScheme = new Cesium.WebMercatorTilingScheme({
        rectangleSouthwestInMeters: southwestInMeters,
        rectangleNortheastInMeters: northeastInMeters
    });
    this._rectangle = this._tilingScheme.rectangle;
    var resource = Cesium.Resource.createIfNeeded(options.url);
    this._resource = resource;
    this._tileDiscardPolicy = undefined;
    this._credit = undefined;
    this._readyPromise = undefined;
}

Object.defineProperties(BaiduImageryProvider.prototype, {
    url: {
        get: function () {
            return this._resource.url;
        }
    },
    proxy: {
        get: function () {
            return this._resource.proxy;
        }
    },
    tileWidth: {
        get: function () {
            if (!this.ready) {
                throw new Cesium.DeveloperError('tileWidth must not be called before the imagery provider is ready.');
            }
            return this._tileWidth;
        }
    },

    tileHeight: {
        get: function () {
            if (!this.ready) {
                throw new Cesium.DeveloperError('tileHeight must not be called before the imagery provider is ready.');
            }
            return this._tileHeight;
        }
    },

    maximumLevel: {
        get: function () {
            if (!this.ready) {
                throw new Cesium.DeveloperError('maximumLevel must not be called before the imagery provider is ready.');
            }
            return this._maximumLevel;
        }
    },

    minimumLevel: {
        get: function () {
            if (!this.ready) {
                throw new Cesium.DeveloperError('minimumLevel must not be called before the imagery provider is ready.');
            }
            return this._minimumLevel;
        }
    },

    tilingScheme: {
        get: function () {
            if (!this.ready) {
                throw new Cesium.DeveloperError('tilingScheme must not be called before the imagery provider is ready.');
            }
            return this._tilingScheme;
        }
    },

    tileDiscardPolicy: {
        get: function () {
            if (!this.ready) {
                throw new Cesium.DeveloperError('tileDiscardPolicy must not be called before the imagery provider is ready.');
            }
            return this._tileDiscardPolicy;
        }
    },

    rectangle: {
        get: function () {
            if (!this.ready) {
                throw new Cesium.DeveloperError('rectangle must not be called before the imagery provider is ready.');
            }
            return this._rectangle;
        }
    },

    errorEvent: {
        get: function () {
            return this._errorEvent;
        }
    },
    ready: {
        get: function () {
            return this._resource;
        }
    },
    readyPromise: {
        get: function () {
            return this._readyPromise;
        }
    },
    credit: {
        get: function () {
            if (!this.ready) {
                throw new Cesium.DeveloperError('credit must not be called before the imagery provider is ready.');
            }
            return this._credit;
        }
    },
});

BaiduImageryProvider.prototype.requestImage = function (x, y, level, request) {
    var r = this._tilingScheme.getNumberOfXTilesAtLevel(level);
    var c = this._tilingScheme.getNumberOfYTilesAtLevel(level);
    var s = this.url.replace("{x}", x - r / 2).replace("{y}", c / 2 - y - 1).replace("{z}", level).replace("{s}", Math.floor(10 * Math.random()));
    return Cesium.ImageryProvider.loadImage(this, s);
};

开发初始化项目中使用

 Cesium.Ion.defaultAccessToken = "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJqdGkiOiIyZmM3OTY4YS1lMzgyLTQ1NTktOTUxNi1hYTAwZTgxYzRmMDYiLCJpZCI6NTE1MjIsImlhdCI6MTYxODE5NTEyOH0.6ZTCtmnrtslvMlO2VLNOh8GEPv63LFrgQyW3GnSNuxE";
      Window.viewer = new Cesium.Viewer("container", {
        infoBox: false,
        selectionIndicator: false,
        navigation: false,
        animation: false,
        timeline: false,
        baseLayerPicker: false,
        geocoder: false,
        homeButton: false,
        sceneModePicker: false,
        navigationHelpButton: false,
        shouldAnimate: true,
        fullscreenButton: false,
        contextOptions: {
          webgl: {
            alpha: true,
            depth: false,
            stencil: true,
            antialias: true,
            premultipliedAlpha: true,
            preserveDrawingBuffer: true,
            failIfMajorPerformanceCaveat: true,
          },
          allowTextureFilterAnisotropic: true,
        },
        requestRenderMode: true, //降低应用中Cesium的CPU使用率。
         imageryProvider: new BaiduImageryProvider({
           url: "http://online{s}.map.bdimg.com/onlinelabel/?qt=tile&x={x}&y={y}&z={z}&styles=pl&scaler=1&p=1",
        }),
      });
 		// 分辨率调整函数
      let adjustmentPixel = function () {
        // 判断是否支持图像渲染像素化处理
        var supportsImageRenderingPixelated =
           Window.viewer.cesiumWidget._supportsImageRenderingPixelated;
        if (supportsImageRenderingPixelated) {
          // 直接拿到设备的像素比例因子 - 如我设置的1.25
          var vtxf_dpr = window.devicePixelRatio;
          // 这个while我们在后面会做一个说明，但不是解决问题的说明
          while (vtxf_dpr >= 2.0) {
            vtxf_dpr /= 2.0;
          }
          // 设置渲染分辨率的比例因子
           Window.viewer.resolutionScale = vtxf_dpr;
        }
      };
      adjustmentPixel();

这个是源码使用百度底图的方法，还有另外一种加载插件可以加载百度底图和其他底图

cesiumMap插件（可加载腾旭、天地图、高德、谷歌地图）

gitee插件地址https://gitee.com/xiaolongshiyl/cesium-map