Specifying behavior and semantic meaning in an unmodified layered drawing package

In order to create and use rich custom appearances, designers are often forced to introduce an unnatural gap into the design process. For example, a designer creating a skin for a music player must separately specify the appearance of the elements in the music player skin and the mapping between these visual elements and the functionality provided by the music player. This gap between appearance and semantic meaning creates a number of problems. We present a set of techniques that allows designers to use their preferred drawing tool to specify both appearance and semantic meaning. We demonstrate our techniques in an unmodified version of Adobe Photoshop®, but our techniques are general and adaptable to nearly any layered drawing package.