[SDPhantom]

A method I could think of is to have it scan out, branching off every time it has a choice based on direction from the origin point. I've had experience in writing functions that run recursively though data without the need to call itself. This usually involves building and managing your own data in a stack-like data structure. You end up using more memory instead of increasing your call stack, which is the best way to avoid stack overflows. It'll take a while to write it all from scratch. I'm assuming this would be in PHP?