The Trillium User Interface Design Environment

Trillium is a computer-based environment for simulating and experimenting with interfaces for simple machines. For the past four years it has been use by Xerox designers for fast prototyping and testing of interfaces for copiers and printers. This paper defines the class of “functioning frame” interfaces which Trillium is used to design, discusses the major concerns that have driven the design of Trillium, and describes the Trillium mechanisms chosen to satisfy them.