2d geometric constraints solvers are usually based on BFGS algorithm (https://en.wikipedia.org/wiki/Broyden–Fletcher–Goldfarb–Shanno_algorithm https://en.wikipe

2d geometric constraints solvers are usually based on BFGS algorithm (https://en.wikipedia.org/wiki/Broyden–Fletcher–Goldfarb–Shanno_algorithm https://en.wikipedia.org/wiki/Broyden–Fletcher–Goldfarb–Shan...). This is what we use in Shapr3D for example (http://www.shapr3d.com http://www.shapr3d.com)