1. override
void render(RenderState renderState)

Renders this display object with the given renderState. The display object is rendered without its filters.

Source 

@override
void render(RenderState renderState) {
  for (int i = 0; i < _children.length; i++) {
    DisplayObject child = _children[i];
    if (child.visible && child.off == false) {
      renderState.renderObject(child);
    }
  }
}