1. A method comprising: receiving a multi-layer image comprising (i) a graphical asset layer comprising a set of graphical assets to be rendered as an image and (ii) a graphical metadata layer comprising a set of graphical drawings that are not to be rendered in the rendered image, the set of graphical drawings for specifying information for rendering the set of graphical assets of the graphical asset layer; and rendering the graphical assets of the graphical asset layer based on a set of properties of the set of graphical drawings of the graphical metadata layer.