A Computer Algorithm for the Generation of Three Dimensional Acoustical Forms: Application to an Investigation of the Acoustics of a Fan Shaped Auditorium

An examination of techniques employed for the computer modeling of building forms reveals that a basic approach is to construct 3D shapes by the assembly of individual planar elements, each of which is defined by a sequence of nodes. The geometric forms of auditoria are analysed and it is shown that the majority can be categorized in terms of a limited number of basic plan forms and cross sections. It is proposed that most of these basic categories can be collapsed to yield a single generic plan form and a single generic cross section that can be simply defined in terms of a number of node co-ordinates. An algorithm is developed for the rapid generation of 3D models of auditoria from the input of a limited number of dimensions related to the generic plan and sections identified in the earlier part of the paper. A number of models generated using this technique have been employed to investigate the effectiveness of stepped walls in general purpose auditoria with a wide fan shaped plan. The results obtained...