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Author SHA1 Message Date
3e59bf1d6a tests/update: Cover guerrilla shootout
This exposes bugs.  They're marked "BUG:" in the test input.

Signed-off-by: Markus Armbruster <armbru@pond.sub.org>
2017-08-06 20:09:19 +02:00
c5df505c98 update: Reorder unit building and maintenance for fairness
The update visits ships, planes and land units in increasing order of
country number.  Within a country, it visits first ships, then planes,
then land units, each in increasing order of unit number.

The order is relevant when money, materials and work don't suffice to
build everything.

Money is charged to the owner, so only the relative order for the same
owner matters there.  One order is as good as any.

Work and materials come from the sector, so only the relative order in
each sector matters.  The current order unfairly prefers countries
with lower country numbers.  Mitigating factor: the affected countries
need to be friendly (ships only) or allied.

The unfairness goes back to Chainsaw's option BUDGET.  See the commit
before previous for more detailed historical notes.

The update test demonstrates the unfair behavior: sector 14,6 builds
ships 95/97 owned by country#1, but not 96 owned by country#7.
Likewise, planes 95/96/97 and land units 95/96/97.

Go back to the the pre-BUDGET order: first ships, then planes, then
land units, all in increasing order of unit number, regardless of
owner.

The update test now builds ship, plane and land unit 96 instead of 97.

Bonus: speeds up both the update and budget by a similar absolute
amount.  For budget, this is roughly a factor of two in my testing.
For the update, which does much more, it's around 10%.

Signed-off-by: Markus Armbruster <armbru@pond.sub.org>
2017-08-06 20:08:31 +02:00
ae2ae938b5 update: Saner rounding of unit building money and work
shiprepair() limits the efficiency gain to how much the workers can
build, rounding randomly.  It charges work, money and materials for
the efficiency actually gained, rounding work up, money down, and
materials randomly.  Same for planerepair() and landrepair().  Has
always been that way.

If you get lucky with the random rounding, you may get a bit of extra
work done for free.

The budget command runs the update code, and can be off by one due to
different random rounding.

Sector production used to have the same issue, only more serious,
because a single unit of tech production matters much more for the
budget than a single point of unit efficiency gain.  I fixed it in
commit 6f7c93c, v4.3.31.

Fix it for unit building the same way: limit efficiency gain to the
amount the workers can produce (no rounding).  Work becomes a hard
limit, not subject to random fluctuations.  Randomly round work and
money charged for actual gain, like we do for materials.  On average,
this charges exactly the work and money that's used.

This lets budget predict how much gets built a bit more accurately.
It's still not exact, as the amount of work available for building
remains slightly random, and the build cost is randomly rounded.

The old rounding of work for ships carries the comment "I didn't use
roundavg here, because I want to penalize the player with a large
number of ships."  Likewise for planes.  Rounding work up rather than
randomly increases the work cost by 0.5 per ship, plane or land unit
on average.  I could keep the penalty by adding 0.5 before random
rounding.  Not worth it, since the effect is actually pretty trivial.
Let's examine a fairly extreme case: an airfield with 600 available
work repairing a huge number of lightly damaged planes, say f2 with
81% average efficiency.  The old code lets the airfield repair roughly
600 / 6.5 = ~92 planes, the new code 600 / 6 = 100.

Signed-off-by: Markus Armbruster <armbru@pond.sub.org>
2017-08-06 19:59:58 +02:00
3bcad4c0dc update: Enforce sector population limit only right after growth
The update kills people to enforce sector population limits, right
after growing people.

However, the population limit may decrease between that killing and
the end of the update:

* Research declines (only with RES_POP), but the lower population
  limit isn't enforced.  Even with an insanely fast decline of 60%
  (level_age_rate = 1, etu_per_update = 60), the population limit
  decreases by less than 10%.

  Not applying the new level to this update is consistent with how we
  use levels elsewhere.

* upd_buildeff() changes sector type and efficiency, but a lower new
  population limit is enforced only when this changes the sector type
  from big city to not big city (since option BIG_CITY was added in
  Empire 2).

  It isn't enforced on other sector type changes.  Might change the
  population limit since the type's limit became configurable in
  commit 153527a (v4.2.20).  Sane configurations don't let players
  redesignate sectors to a type with different maximum population.
  The server doesn't enforce this, though.

  It isn't enforced when a big city's efficiency decreases, but sector
  type change isn't achieved.  Having population exceed the new limit
  without having produced enough work to change the type seems
  unlikely, as 25 will do even in the worst case, but should be
  possible with a sufficiently low work percentage.

  None of this is documented in info Update-sequence.  Inconsistent
  mess.  Drop it.

Signed-off-by: Markus Armbruster <armbru@pond.sub.org>
2017-08-06 19:59:56 +02:00
14af586b57 tests/update: New; exercises the update
Notable gaps in its coverage are fallout, most of guerrilla, delivery,
distribution, ALL_BLEED and LOSE_CONTACT.

Signed-off-by: Markus Armbruster <armbru@pond.sub.org>
2017-08-06 14:04:15 +02:00