CONSTRAINT-SOLVING IN INTERACTIVE GRAPHICS A USER-FRIENDLY APPROACH

Abstract

Solving constraints is an important part of interactive graphics, and a number of constraint solvers that operate in this domain have been designed and implemented. However, most of these systems are deficient in two respects: the method of specifying constraints is counter-intuitive, and only a restricted class of constraints is representable. After describing the problems inherent in current systems, we propose a simple constraint solver and its user interface, Metamouse. The user of this system specifies constraints by giving examples in the form of execution traces; the system induces a generalized procedure. Thus constraint specification is natural-the user simply performs his task as usual-and the class of representable constraints includes anything the user could accomplish manually with the graphics editor.