Economic Districts

[bunnybot]

Mirrored from Codeberg
Created on Tue Feb 06 19:59:44 CET 2024 by Benedikt Straub (Nordfriese)

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Type of change
New feature for v1.3

Issue(s) closed
This addresses several points that arise frequently in the context of very large games – namely the problem of wares (and also workers) being transported across long distances instead of preferring local supplies.

How it works
These points all happen in the background. The UI is unchanged.

Each economy automatically divides itself into districts. A district is centered around a warehouse (multiple warehouses in close proximity are clustered for this purpose), and each flag belongs to the closest warehouse. Thus, a district is a circle around a warehouse or cluster of warehouses.

Districts try to be self-sufficient and minimize imports.
Supply/request matching always prefers to use supplies from the same district. Imports are only accepted if no local supply is available.

New: All active long-distance imports are frequently monitored, and if a ware becomes available in the local district, the import is cancelled and replaced with the local ware. This type of supply exchanging was previously always rejected as too CPU-intensive, but this approach is performant and catches all the cases where it matters most.

Additionally, economy targets are distributed across districts. Global targets (global here meaning within one economy) continue to work as before. In addition, if a district is short of a specific ware, then the productionsites within this district keep producing even if the global stock is above target. Each district's local target is simply the global target divided by number of districts, rounding up.

Possible regressions
Economic request/supply matching, economy targets.

Screenshots

Additional context
Nothing here needs to be saveloaded. This is all recalculated lazily every few seconds.
Benchmark for a nearly completely conquered Accurate Europe 1.0 map, Release build:

[00:02:38.430 real] INFO: NOCOM Recalcing districts for 5376 flags and 34 warehouses took 7 ms
[00:02:38.434 real] INFO: NOCOM Checking imports for 5376 flags and 34 warehouses took 3 ms

Flags at the border between two districts tend to jitter between the two possible districts due to pseudo-randomness in the routing algorithm. I would not consider this a problem.

Could do with more testing, both with big economies and with small ones. I'd therefore like to have this early in the release cycle for v1.3.

[bunnybot]

Assigned to Nordfriese

[bunnybot]

Mirrored from Codeberg
On Tue Feb 20 15:14:18 CET 2024, ** (frankystone)* wrote:*

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Does this change anything related to economy worker settings?

In the attached save game the barracks produce soldiers endlessly, 'stealing' the wares needed to create heroes. Starting this save game in master the soldier production stops, because economy setting says 10 soldiers and there are already more than 40 sitting around.

In debug builds the game stutters for me every time the district calculation is made. Probably because of the debug things.

[bunnybot]

Mirrored from Codeberg
On Tue Feb 20 15:48:29 CET 2024, Benedikt Straub (Nordfriese) wrote:

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Ah yes…
if you have 4 warehouses and a soldier target setting of 10, then each warehouse's district target is ceil(10/4) = 3 soldiers. However the barracks is in the HQ district and the HQ's stock policy for soldiers is kRemove, so the barracks district can never reach its local target.

So for districts where a ware/worker is not meant to be stored in warehouses this check won't work. And if some other (foreign) warehouse has a Prefer policy for that ware/worker but we don't Prefer it locally then too it won't work.

I'll create a commit to take these stock policies into account and skip the local target check if the warehouse policies interfere with district target distribution.

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In debug builds the game stutters for me every time the district calculation is made. Probably because of the debug things.

For me debug builds with such large maps stutter on every economy update anyway ;) What times does the log print out for district recalculation and imports checking? For me this is always 1ms each with your savegame in a debug build (i.e. negligibly fast).