Geometric Constraint Solving

Geometric constraint solving (GCS) is one of the key techniques in parametric CAD, which allows the user to make modifications to existing designs by changing parametric values. GCS methods may also be used in other fields like molecular modelling, robotics and computer vision.

There are four major approaches to GCS:
1) the numerical approach
2) the symbolic approach
3) the rule-based approach and
4) the graph-based approach