The machine refinement of raw graphic data for translation into a low level data base for computer aided architectural design (CAAD).

It is argued that a significant feature which acts as a disincentive against the adoption of CAAD systems by small private architectural practices, is the awkwardness of communicating with computers when compared with traditional drawing board techniques. This consideration, although not perhaps the dominant feature, may be mitigated by the development of systems in which the onus of communicating is placed on the machine, through the medium of an architect's sketch plan drawing. In reaching this conclusion, a design morphology is suggested, in which the creative generation of building designs is set in the context of the development of a 'data-base' of information which completely and consistently describes the architect's hypothetical building solution. This thesis describes research carried out by the author between 1981 and 1984, and describes the theory, development and application of algorithms to interpret architect's sketch plan drawings, and hence permit the encoding of building geometries for CAAD applications programs