A declarative formalism for specifying graphical layout

An approach to specifying graphical layouts of arbitrary objects, based on a T_EX-like notation, is described. The simplest scheme offers specifications similar to T_EX's box-and-glue metaphor. Size and position of boxes and glue can be specified by constraints. Advantages of this T_EX-like formalism are its expressiveness, user-predictable layouts, and efficient implementation schemes for the underlying layout algorithms. This forms-oriented scheme is extended and generalized for specifying advanced graphical user interfaces (e.g. CLOS class browser).