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) {
  if (renderState.renderContext is RenderContextWebGL) {
    _renderWebGL(renderState);
  } else {
    _renderCanvas2D(renderState);
  }
}