Cesium 基于MapBox底图加载3DTiles 模型

3dtiles 模型采用   catia v5 r22 ---> hsf+sqlite --->glb--->b3dm 

var extent = cesium.rectangle.fromdegrees(75, 60.808406, 135.313421, 10);
cesium.camera.default_view_rectangle = extent;
cesium.camera.default_view_factor = 0;
cesium.ion.defaultaccesstoken = "你的token";
cesium.creditdisplay.cesiumcredit = "测试";
var viewer = new cesium.viewer('cesiumcontainer', {
    animation: false,//是否创建动画小器件，左下角仪表
    baselayerpicker: false,//是否显示图层选择器
    fullscreenbutton: true,//是否显示全屏按钮
    geocoder: true,//是否显示geocoder小器件，右上角查询按钮
    homebutton: true,//是否显示home按钮
    infobox: false,//是否显示信息框
    scenemodepicker: true,//是否显示3d/2d选择器
    selectionindicator: false,//是否显示选取指示器组件
    timeline: false,//是否显示时间轴
    navigationhelpbutton: false,//是否显示右上角的帮助按钮
    scene3donly: true,//如果设置为true，则所有几何图形以3d模式绘制以节约gpu资源
    clock: new cesium.clock(),//用于控制当前时间的时钟对象
    selectedimageryproviderviewmodel: undefined,//当前图像图层的显示模型，仅baselayerpicker设为true有意义
    //imageryproviderviewmodels: cesium.createdefaultimageryproviderviewmodels(),//可供baselayerpicker选择的图像图层providerviewmodel数组
    selectedterrainproviderviewmodel: undefined,//当前地形图层的显示模型，仅baselayerpicker设为true有意义
    terrainproviderviewmodels: cesium.createdefaultterrainproviderviewmodels(),//可供baselayerpicker选择的地形图层providerviewmodel数组
    skybox: new cesium.skybox({
        sources: {
            positivex: '/build/cesium/assets/textures/skybox/tycho2t3_80_px.jpg',
            negativex: '/build/cesium/assets/textures/skybox/tycho2t3_80_mx.jpg',
            positivey: '/build/cesium/assets/textures/skybox/tycho2t3_80_py.jpg',
            negativey: '/build/cesium/assets/textures/skybox/tycho2t3_80_my.jpg',
            positivez: '/build/cesium/assets/textures/skybox/tycho2t3_80_pz.jpg',
            negativez: '/build/cesium/assets/textures/skybox/tycho2t3_80_mz.jpg'
        }
    }),//用于渲染星空的skybox对象
    fullscreenelement: document.body,//全屏时渲染的html元素,
    usedefaultrenderloop: true,//如果需要控制渲染循环，则设为true
    targetframerate: undefined,//使用默认render loop时的帧率
    showrenderlooperrors: false,//如果设为true，将在一个html面板中显示错误信息
    automaticallytrackdatasourceclocks: true,//自动追踪最近添加的数据源的时钟设置
    contextoptions: undefined,//传递给scene对象的上下文参数（scene.options）
    scenemode: cesium.scenemode.scene3d //初始场景模式
});

var mapbox = new cesium.mapboximageryprovider({
    mapid: 'mapbox.satellite',
    accesstoken: '你的token'
});
viewer.imagerylayers.addimageryprovider(mapbox);

var tileset = viewer.scene.primitives.add(new cesium.cesium3dtileset({ url: '/files/test/tileset.json' }));
viewer.scene.primitives.add(tileset);

tileset.readypromise.then(function (tileset) {
    viewer.scene.primitives.add(tileset);
    viewer.zoomto(tileset, new cesium.headingpitchrange(0.5, -0.2, tileset.boundingsphere.radius * 1.0));
}).otherwise(function (error) {
    console.log(error);
});

cesium.creditdisplay.cesiumcredit = null;
// 创建div标签
var bubblediv = document.createelement('div');
viewer.container.appendchild(bubblediv);
bubblediv.classname = 'bubble';
bubblediv.style.display = 'none';
bubblediv.style.position = 'absolute';
bubblediv.style.bottom = '0';
bubblediv.style.left = '0';
bubblediv.style['pointer-events'] = 'none';
bubblediv.style.padding = '4px';
bubblediv.style.zindex = 100;

// 有关当前选定功能的信息
var selected = {
    feature: undefined,
    originalcolor: new cesium.color()
};
var selectedentity = new cesium.entity();
// 获取默认的鼠标左键处理程序
var clickhandler = viewer.screenspaceeventhandler.getinputaction(cesium.screenspaceeventtype.left_click);
// 如果不支持轮廓，请在鼠标悬停时将特征颜色更改为黄色，在单击鼠标时将特征颜色更改为绿色。
if (cesium.postprocessstagelibrary.issilhouettesupported(viewer.scene)) {
    //支持剪影
    var silhouetteblue = cesium.postprocessstagelibrary.createedgedetectionstage();
    silhouetteblue.uniforms.color = cesium.color.blue;
    silhouetteblue.uniforms.length = 0.01;
    silhouetteblue.selected = [];

    var silhouettegreen = cesium.postprocessstagelibrary.createedgedetectionstage();
    silhouettegreen.uniforms.color = cesium.color.lime;
    silhouettegreen.uniforms.length = 0.01;
    silhouettegreen.selected = [];

    viewer.scene.postprocessstages.add(cesium.postprocessstagelibrary.createsilhouettestage([silhouetteblue, silhouettegreen]));

          viewer.screenspaceeventhandler.setinputaction(function onleftclick(movement) {
            // 如果先前选择了功能，请撤消突出显示
            silhouettegreen.selected = [];

            // p选择一个新功能
            var pickedfeature = viewer.scene.pick(movement.position);
            if (!cesium.defined(pickedfeature)) {
                clickhandler(movement);
                return;
            }

            //选择功能（如果尚未选择）
            if (silhouettegreen.selected[0] === pickedfeature) {
                return;
            }
            // 保存所选功能的原始颜色
            var highlightedfeature = silhouetteblue.selected[0];
            if (pickedfeature === highlightedfeature) {
                silhouetteblue.selected = [];
            }
            //突出显示新选择的功能
            silhouettegreen.selected = [pickedfeature];
        }, cesium.screenspaceeventtype.left_click);
 var highlighted = {
        feature: undefined,
        originalcolor: new cesium.color()
    };

    //将特征悬停上色为黄色。
    viewer.screenspaceeventhandler.setinputaction(function onmousemove(movement) {
        //如果以前突出显示某个功能，请撤消突出显示
        if (cesium.defined(highlighted.feature)) {
            highlighted.feature.color = highlighted.originalcolor;
            highlighted.feature = undefined;
        }
        // 选择一个新功能
        var pickedfeature = viewer.scene.pick(movement.endposition);
        if (!cesium.defined(pickedfeature)) {
            bubblediv.style.display = 'none';
            return;
        }
        // 选择了某项功能，因此请显示其叠加内容
        bubblediv.style.display = 'block';
        bubblediv.style.bottom = viewer.canvas.clientheight - movement.endposition.y + 'px';
        bubblediv.style.left = movement.endposition.x + 'px';
        var name = pickedfeature.getproperty('name');
        if (!cesium.defined(name)) {
            name = pickedfeature.getproperty('id');
        }
        bubblediv.textcontent = name;
        // 突出显示该功能（如果尚未选择）
        if (pickedfeature !== selected.feature) {
            highlighted.feature = pickedfeature;
            cesium.color.clone(pickedfeature.color, highlighted.originalcolor);
            pickedfeature.color = cesium.color.yellow;
        }
    }, cesium.screenspaceeventtype.mouse_move);
}

 结果发现mapbox 地图加载也太慢了，不知道是我们单位的网不好，还是本身就慢。