How do I find object at 0,90,180 and 270 degrees

I am making a Pacman clone and am using a series of nodes for the ghost movement. How do I find the uid of the nearest nodes to to the points in the description?

Of course I want to find these when the ghost has reached a node.

This is a good tutorial

https://www.construct.net/en/tutorials/cloning-classics-pacman-171