CGLIB: http://www.probp.com/cglib/

CGLIB is a constraint-based high-level graphics library developed for B-Prolog.^21.1 It supports over twenty types of basic graphical objects and provides a set of constraints including non-overlap, grid, table, and tree constraints that facilitates the specification of layouts of objects. The constraint solver of B-Prolog serves as a general-purpose and efficient layout manager, which is significantly more flexible than the special-purpose layout managers used in Java. The library adopts action rules available in B-Prolog for creating agents and programming interactions among agents or between agents and users. CGLIB is supported in the Windows version only.^21.2