[Freeciv-Dev] Re: [FreeCiv-Cvs] jjm: Fixes city_turns_to_build() to consider the 1 s...

[David Pfitzner <dwp@xxxxxxxxxxxxxx>]

Steven Burnap <sburnaplinux@xxxxxxx> wrote:

> Mike Jing wrote:
> 
> > That's not exactly what we are talking about.  I don't know if you have ever
> > tried this in Freeciv, but as it stands now, if a city has no shield surplus
> > due to supporing units, e.g. it has "prod: 1 (+0)", it still gets one shield
> > added to it's shield stock every turn.  Could you check if it does this in
> > Civ1?
>  
> I just check Civ 1.  It is the same as Civ 2.  If you have no shield 
> surplus, you produce nothing.

I just checked Civ1 too, and sort of verified my recollection
that you do get production, but the real explanation turns out
to be more complicated...

After much experimentation I found there is either a rule I never
knew, or more likely a bug, combined with an inconsistency in 
the Civ1 city dialog such that the rule/bug is not taken into
account there.

The effect is as follows: For each city, consider the military
units supported by that city which are fortified in the city.
(Fully fortified, with a solid square around them, ie, fortified
for more than one full turn.)  Only the first such unit has 
real shield upkeep, in terms of shields added to the shield 
stock at the end of the turn.  However in the city dialog all 
such units appear to have upkeep, and the surplus display is 
calculated as though they all have upkeep.

My recollection was based on a typical case of a city with
two fortified units.  That gives 1 more production than shown
in the display, thus giving 1 production even when the shown 
surplus is zero.  But the rule is more general, as described 
above, and if you have a surplus you can get "bonus" surplus
for extra fortfied units, or you can have an apparent deficit 
(a black shield) but really have no deficit or even have an 
effective surplus.

(I vaguely recall once before finding strangeness in the Civ1
behavour of forced-disbanding units when a city has a shield
deficit, but cannot now find it in the list archives.  Anyway,
the above effect probably explains such strangeness.)

Anyway, this all seems like a bug, since with this "rule"
you could build up a huge stock of defenders without having
to upkeep them.  And thus 0 surplus should mean 0 surplus,
for both Civ1 and Civ2.

-- David