anchor.diff:          h = 0;
       if (horizontalAlign != HorizontalAlign.LEFT || verticalAlign != HorizontalAlign.LEFT) {
         container.forEach((int i, DisplayObject child) {
  +        if (!child.visible) return;
           if (orientation == Orientation.HORIZONTAL) {
             w += child.width + gap;
             h = h > child.height ? h : child.height + gap;
  
positive.code:       step = (child) => starty += child.height + gap;
      }
      container.forEach((i, child) {
        child.x = startx;
        child.y = starty;
        step(child);
  
negative.code:   VerticalAlign verticalAlign;
    Orientation orientation;
  
    LinearLayout({this.gap: 0, this.orientation: Orientation.HORIZONTAL, this.horizontalAlign:
        HorizontalAlign.LEFT, this.verticalAlign: VerticalAlign.TOP, this.padding: 0});
  
    @override
    order(Component container) {
  