Visual languages for sketching documents

We present a visual approach to layout documents as hand-drawn compositions of simple geometric shapes. This approach is based on a grammatical method to support document design through sketch recognition which explicitly addresses visual ambiguity. We use fuzzy relational adjacency grammars to provide a natural handling of fuzzy logic and spatial relation syntax in a single unified formalism. Fuzzy relations enable us to replace spatial constraints such as “a is above b” or “a is parallel to c” by quantities that express a degree of uncertainty. Their use allows us to associate a “measure of goodness” to all data and to intermediate and final results. We developed a prototype application that supports document layout sketching in a simple way