Linkedit : an interactive graphical system for modeling objects with constraints

A constraint describes a relation that must be maintained. Constraints provide a useful method to aid in the construction and animation of mechanisms. In this paper, a geometric constraint system called LinkEdit is presented. LinkEdit system provides a tool for interactive animation of objects constructed from rigid primitives, demonstrating the power of constraints as a method for specifying several types of constraints between constrained three-dimensional objects. LinkEdit system is designed to handle constraints without cycles, by combining SkyBlue and QuickPlan constraint solvers to eff iciently maintain constraints organized in a constraint hierarchy.