D568/rP20608 introduced a range visualization overlay for ranged attacks and added it to arrow-shooting structures as well as moveable siege towers, though not for other units. The reasoning was that soldiers are selected too frequently; they're also present in large numbers.
This patch adds it to bolt-shooters, stone-throwers, fireraisers, and quinquerenes as well.
- Artillery is not as mobile as soldiers (they have to un/pack) and their very high attack range and damage combined with their very poor reload time make it desirable to know how far they can shoot. Moreover, they have a minimum range, which is important information to convey.
Here is how it looks in game:
- While fireraisers have a relatively small attack range, they are ranged siege engines and do have a minimum range.
- Like artillery, quinqueremes have high attack range and poor reload time, as well as a minimum range. Furthermore, they're very large and have BuildingAI, like structures and siege towers.
Other warships didn't get an attack overlay. Although they're quite large and have BuildingAI too, they don't have a minimum range, shoot more frequently, and are more common (on water maps, that is).