Theoretical and experimental results from the implementation of a system for computer-aided floor-plan design are reported. The system is based on a potentially exhaustive search for solutions that satisfy user-specified constraints, but the paper concentrates on techniques for limiting and guiding the search. The emphasis is on two aspects of floor-plan design: the use of a formalized concept of sketching, and the language in which design constraints are specified by the user. A well-defined concept of abstract draft plans is achieved by limiting corner coordinates to intervals, rather than single numbers. Mathematical properties of drafts and their defining constraints as derived from the user's constraints are outlined, and the role of drafts in computer-aided floor-plan design is investigated and illustrated by examples. The specification language is based on a small set of primitives whose combined power of expression is also illustrated. The syntax and semantics of the language are formally defined (in two appendices), and the importance of careful development of languages for future design automation is pointed out.
