New DLL functionality: isFreshWater() [IMPLEMENTED]

[Mate-86]

That is already happening with a normal River and I feel that I should leave it like that.
The main difference with "isFreshWater()" is that it also considers adjacent Terrains "Lakes", "Ice Lakes" and "Large Rivers".

Thank you for your detailed explanation! I should have known better how the game already works regarding the river tile yields. Irrigation from Large rivers and Lakes is nice to have but probably not super important.
As others already suggested we may discuss the food yields in a dedicated thread.

 

[modmod]

Irrigation now exists in branch "Plains" as well, but it only possible in Deserts and also requires Rivers.
(It is more or less impossible in current maps or mapscripts anyways that Deserts will have any fresh water lakes.)

Idea 1.
What if isFreshWater() create the same effect as rivers (eg. makes possible irrigation canal)?
Even if that source is in the other end of the current settlement, as it can check the city have fresh water access or not in all the 2 plot radius (so like in 4 plots distance).

Idea 2.
Plenty of fresh water can improve a few industries.
Like never heard about that blacksmits or tanners used salt water (is that possible?).

Idea 3.
If there are no (plenty) fresh water access, but there are en masse industry that can carry a slight negative effect for health and/ or happiness. (Scarce drinking water sources used for industrial purpose.)

Idea 4.
A few building can use the feature, like:

• well provides additional health bonus

• a new fountain building
• a new fish pound building (or feature?)