var worldTerrain = Cesium.createWorldTerrain({
    requestWaterMask: true,
    requestVertexNormals: true
});

var viewer = new Cesium.Viewer('cesiumContainer', {
    terrainProvider: worldTerrain,
    timeline: false,
    animation: false,
    baseLayerPicker: true,
    fullscreenButton: false,
    geocoder: false,
    homeButton: false,
    sceneModePicker: false,
    scene3DOnly: true,
    shadows: false
});

viewer.scene.frameState.creditDisplay.destroy();
viewer.baseLayerPicker.viewModel.selectedImagery = viewer.baseLayerPicker.viewModel.imageryProviderViewModels[9];

function addTileset(url_, heightOffset = 0.0)
{
    var tileset_ = viewer.scene.primitives.add(new Cesium.Cesium3DTileset({
        url: url_,
        maximumScreenSpaceError: 1,
        //shadows: Cesium.ShadowMode.DISABLED,
        skipLevelOfDetail: false
    }));

    tileset_.readyPromise.then(function (tileset)
    {
        // Position tileset
        var boundingSphere = tileset.boundingSphere;
        var cartographic = Cesium.Cartographic.fromCartesian(boundingSphere.center);
        var surface = Cesium.Cartesian3.fromRadians(cartographic.longitude, cartographic.latitude, 0.0);
        var offset = Cesium.Cartesian3.fromRadians(cartographic.longitude, cartographic.latitude, heightOffset);
        var translation = Cesium.Cartesian3.subtract(offset, surface, new Cesium.Cartesian3());
        tileset.modelMatrix = Cesium.Matrix4.fromTranslation(translation);
    });

    return tileset_;
}

viewer.entities.removeAll();

var tileset = addTileset('/3dTilesets/kremlin/tileset.json', 2.0);

viewer.zoomTo(tileset)
    .otherwise(function (error) {
        console.log(error);
    });