This paper describes a simple two stage algorithm for finding emergent sub-shapes in shapes, in the context of shape grammar systems. Matching the shape in the left side of a rule of a shape grammar with parts of a shape in a design in process to decide if the rule is applicable, is its main purpose. Shape grammars have been used to represent the knowledge behind the creative work of architects, designers and artists and allow the implementation of computational mechanisms to analyze and synthesize designs of visual languages, with obvious applications to design, including for marketing. Their computational mechanisms can include the detection of emergent sub-shapes. The algorithm we propose performs this task and is a core component of a system, described in our past work, that allows users to build their own shape grammars and use them.

This work was undertaken at ISTAR-Information Sciences and Technologies and Architecture Research Center from ISCTE-Instituto Universitário de Lisboa (University Institute of Lisbon), Portugal, and it was partially funded by the Portuguese Foundation for

Shape grammars,Artificial intelligence,Design

• Computer and Information Sciences - Natural Sciences