How to use the @swim/view.View.NeedsAnimate function in @swim/view

doUpdate(updateFlags: number, viewContext: MapViewContext): void {
    const layerViewContext = this.layerViewContext(viewContext);
    this.willUpdate(layerViewContext);
    if (((updateFlags | this._updateFlags) & View.NeedsCompute) !== 0) {
      this._updateFlags = this._updateFlags & ~View.NeedsCompute;
      this.doCompute(layerViewContext);
    }
    if (((updateFlags | this._updateFlags) & View.NeedsAnimate) !== 0) {
      this._updateFlags = this._updateFlags & ~View.NeedsAnimate;
      this.doAnimate(layerViewContext);
    }
    if (((updateFlags | this._updateFlags) & MapView.NeedsProject) !== 0) {
      this._updateFlags = this._updateFlags & ~MapView.NeedsProject;
      this.doProject(layerViewContext);
    }
    if (((updateFlags | this._updateFlags) & View.NeedsLayout) !== 0) {
      this._updateFlags = this._updateFlags & ~View.NeedsLayout;
      this.doLayout(layerViewContext);
    }
    if (((updateFlags | this._updateFlags) & View.NeedsScroll) !== 0) {
      this._updateFlags = this._updateFlags & ~View.NeedsScroll;
      this.doScroll(layerViewContext);
    }
    if (((updateFlags | this._updateFlags) & View.NeedsRender) !== 0) {

doUpdate(updateFlags: number, viewContext: MapViewContext): void {
    const layerViewContext = this.layerViewContext(viewContext);
    this.willUpdate(layerViewContext);
    if (((updateFlags | this._updateFlags) & View.NeedsCompute) !== 0) {
      this._updateFlags = this._updateFlags & ~View.NeedsCompute;
      this.doCompute(layerViewContext);
    }
    if (((updateFlags | this._updateFlags) & View.NeedsAnimate) !== 0) {
      this._updateFlags = this._updateFlags & ~View.NeedsAnimate;
      this.doAnimate(layerViewContext);
    }
    if (((updateFlags | this._updateFlags) & MapView.NeedsProject) !== 0) {
      this._updateFlags = this._updateFlags & ~MapView.NeedsProject;
      this.doProject(layerViewContext);
    }
    if (((updateFlags | this._updateFlags) & View.NeedsLayout) !== 0) {
      this._updateFlags = this._updateFlags & ~View.NeedsLayout;
      this.doLayout(layerViewContext);
    }
    if (((updateFlags | this._updateFlags) & View.NeedsScroll) !== 0) {
      this._updateFlags = this._updateFlags & ~View.NeedsScroll;
      this.doScroll(layerViewContext);
    }
    if (((updateFlags | this._updateFlags) & View.NeedsRender) !== 0) {
      this._updateFlags = this._updateFlags & ~View.NeedsRender;

setCoords(coords: AnyLngLat[], tween?: Tween): void {
    let i = 0;
    for (const n = Math.min(this._coords.length, coords.length); i < n; i += 1) {
      const coord = LngLat.fromAny(coords[i]);
      this._coords[i].setState(coord, tween);
    }
    for (const n = coords.length; i < n; i += 1) {
      const coord = LngLat.fromAny(coords[i]);
      this._coords.push(new AnyMemberAnimator(LngLat, this, coord as LngLat));
      this._points.push(PointR2.origin());
      this.requireUpdate(View.NeedsAnimate | MapView.NeedsProject);
    }
    this._coords.length = coords.length;
  }