Cesium 相机视角锁定/取消锁定

 /**相机对准目标位置 */
  public lookAt(params) {
  //position坐标系为CoordType.WGS84
    let { position,offset = [0, 0, 0] } = params;
    if (!position) return;
    var center = Cartesian3.fromDegrees(p[0], p[1], p[2]);
    viewer.camera.lookAt(
      center,
      new Cartesian3(offset[0], offset[1], offset[2])
    );
  }

/**
   * 取消视角锁定
   */
  public cancelLookAt() {
    viewer.camera.lookAtTransform(Matrix4.IDENTITY);
  }