Sketch-based pruning of a solution space within a formal geometric constraint solver Original Research Article

In CAD systems, formal geometric solvers enable the designer to draw a sketch and to provide constraints that are compiled into a construction plan by symbolic geometric reasoning. Then the plan is interpreted in order to generate the required figure. In case there are multiple solutions, they allow to scan the entire solution space. But when the number of solutions becomes too high, it is very time-consuming to examine each of them to determine which one is the closest to the userʹs will. In this paper, we introduce a sketch-based heuristic that enables to easily eliminate most of the solutions and to keep, among a solution space represented by a tree, only one branch, or at the worst a small subtree of solutions, that has the best likeness with the original sketch.