shooting across rivers

[Mr Grumpy]

Well of course we have two types of rivers "full hex" and "hex side", you can only fire across a "full hex" with a weapon with a two hex or more range, but any weapon can fire across a "hex side" river.

So this all depends on who creates the map and the choice of river hex they use, how that decision is reached i am not sure, in some titles there are both types of river hex's and so a decision of which type of river to use must have been based on some criteria?