How to make a design "loose coupling"?

Question

I'm making a simple 3D CAD software. in the class diagram, many objects need to distinguish with others by (x,y,z). I create a class so-called "Position", but the problem is it looks highly-coupling because many classese work with position. Any ideas?

Answer 1

It is not a problem per se if a type is used by many other types. In your case, graphical objects obviously (usually) have a position so the coupling looks natural and reasonable from the perspective of the domain model.

Also, the Position class is probably going to be a fairly low-level class whose interface (and probably implementation too) is not going to change very often in the long run. So there is not much chance of such changes breaking client code.