Cesium 动态改变模型的高度

var viewModel = {
  height: 0,
};

Cesium.knockout.track(viewModel);//把对象关联到Cesium这里用的绑定可以参考观察者模式

var toolbar = document.getElementById("toolbar");//绑定input外的元素的id
Cesium.knockout.applyBindings(viewModel, toolbar);//height和input做绑定，//绑定MV

var tileset = new Cesium.Cesium3DTileset({
  url: "../SampleData/Cesium3DTiles/Tilesets/Tileset/tileset.json",
});

tileset.readyPromise
  .then(function (tileset) {
    viewer.scene.primitives.add(tileset);
    viewer.zoomTo(
      tileset,
      new Cesium.HeadingPitchRange(
        0.0,
        -0.5,
        tileset.boundingSphere.radius * 2.0
      )
    );
  })
  .otherwise(function (error) {
    console.log(error);
  });

Cesium.knockout
  .getObservable(viewModel, "height")
  .subscribe(function (height) {
    height = Number(height);
    if (isNaN(height)) {
      return;
    }

    var cartographic = Cesium.Cartographic.fromCartesian(
      tileset.boundingSphere.center
    );
    var surface = Cesium.Cartesian3.fromRadians(
      cartographic.longitude,
      cartographic.latitude,
      0.0
    );
    var offset = Cesium.Cartesian3.fromRadians(
      cartographic.longitude,
      cartographic.latitude,
      height
    );
    var translation = Cesium.Cartesian3.subtract(
      offset,
      surface,
      new Cesium.Cartesian3()
    );
    tileset.modelMatrix = Cesium.Matrix4.fromTranslation(translation);
  });