I think I may have worded my question wrong let me try again.
I want to change what the unit of measurement is.
In other words if I have a square that is 10 units by 10 units (by default this would be 10 cm by 10 cm). Can I change something in the engine so that those 10 units can be changed to meters or some other measurement of distance?
So I could change this square so it is still 10 by 10 units but now reads as being 10 by 10 meters?