There are some cool global minimisation algorithms which can handle certain types of problem where the initial guess is far away. Some involve switching between

There are some cool global minimisation algorithms which can handle certain types of problem where the initial guess is far away. Some involve switching between different algorithms until the cost function is close to its minimum. I did try the ones available in SciPy when I built a non-linear equation based constraint solver, but none really worked well enough. However, I know such algorithms exist if I put the time in to learn about them. Since I discovered cluster-rewriting based constraint solvers, I've been spending most of my time investigating those. I'm actually not against the idea of asking the user to provide a sketch, I'm just trying to solve the harder problem first and if I can't do so then I'll introduce some constraints (pun not intended).