Coherent processing of character skeletal forms

It is well known that in the general context the similarity relation is very fuzzy and hard to define. Unfortunately, the intuitive notion of similarity is not a transitive relation: knowing that A is similar to B and that B is similar to C does not necessarily imply similarity between A and C. This is a main obstacle when trying to express formally what a coherent font design is. The authors suggest a method to decompose complex letter forms into simpler elements and suggest a formal transitive definition of a similarity relation between these elements. In the context of digital typography, this definition enables developing an algorithm to recover classes of similar elements within different characters of a given font. This knowledge is further exploited to ensure coherent type processing. For example, a modification (e.g. by a type designer) of a character element is propagated automatically to all the other characters that include a similar element. For the moment, the discussion is limited to the class of stroke fonts