City size of 0 prevents many buildings/terrains from spawning

[Noctifer-de-Mortem]

Game version: Experimental Build 7085

Operating system: Windows 10

Tiles or curses: Tiles

Mods active:
"dda",
"Arcana",
"Cata++",
"DinoMod",
"Medieval_Stuff",
"Mining_Mod",
"More_Survival_Tools",
"No_Fungi",
"Sabaton_memes",
"blazemod",
"Tanks",
"boats",
"crazy_cataclysm",
"no_npc_food",
"novitamins",
"realguns"
(Also tested with no mods)

Expected behavior

After #22011 , various different types of buildings and terrain spawn. The player would not be in forest only area.

Actual behavior

It seems that despite being able to, some natural features do not spawn. The area gets some limited spawns but somethings don't seem to spawn at all.

Steps to reproduce the behavior

Create a world with a city size of zero and then start a game in it, scenario is irrelevant. Open the map and notice the lack of interesting features such as cabins and LMOE shelters.

Personal Theory:

((Now, I am not very good at coding and as such was not able to find anything to back this up in the code so if I am wrong, feel free to correct me.))
It looks to me that city size zero is a sort of hack; just lower the city value to city but the map generation still treats it the same as with cities still being a thing. If we add required flags, it seems the spawn rate is fixed but that would affect world with city size of >1. So I was thinking maybe a flag that works like the required flag but only works in city size 0 as a solution?

[kevingranade]

Please list the buildings you expect to appear.

[Noctifer-de-Mortem]

ID "Lake"
ID "Bee Hive"
ID "Anthill"
ID "Spider Pit"
ID "Slime Pit"
ID "Fungal Bloom"
ID "Fungal Tower"
ID "Fungal Flowers"
ID "Triffid Grove"
ID "Cave"

ID "farm_abandoned"
ID "Shipwreck"
ID "LMOE Shelter"
ID "Cabin"
ID "Strange Cabin"
ID "Strangle Temple"
ID "Mansion_Wild"
ID "Toxic Waste Dump"
ID "bandit_cabin"
ID "bandit_camp"
ID "campsite"
ID "campsite_cabin_incomplete"
ID "campsite_field_biker"
ID "campsite_a"
ID "campsite_field_biker_destroyed"
ID "Swamp Shack"

[Reknot]

Actually you can force it for some reason, they seem to spawn hidden. I know "Swamp Shack" and "Cabin" comes up in the save files wihout altering anything, for the rest I made my own custom "overmap_specials.json", see below.
If I run with that, they get placed on the map screen as expected, but only at the Minimum "occurrences" value.

### (can't get the tabs to work proper, sorry for the formatting)

[
{
"type" : "overmap_special",
"id" : "Shipwreck",
"overmaps" : [
{ "point":[0,0,0], "overmap": "shipwreck_river_1"},
{ "point":[1,0,0], "overmap": "shipwreck_river_2"},
{ "point":[0,0,-1], "overmap": "shipwreck_river_3"},
{ "point":[1,0,-1], "overmap": "shipwreck_river_4"}
],
"locations" : [ "water" ],
"occurrences" : [0, 2],
"rotate" : false,
"spawns" : { "group" : "GROUP_RAZORCLAW", "population":[30,60], "radius":[2, 10] }
},{
"type" : "overmap_special",
"id" : "Bee Hive",
"overmaps" : [
{ "point":[0,0,0], "overmap": "hive"},
{ "point":[0,1,0], "overmap": "hive"},
{ "point":[0,2,0], "overmap": "hive"},
{ "point":[1,0,0], "overmap": "hive"},
{ "point":[1,1,0], "overmap": "hive"},
{ "point":[1,2,0], "overmap": "hive"},
{ "point":[2,0,0], "overmap": "hive"},
{ "point":[2,1,0], "overmap": "hive"},
{ "point":[2,2,0], "overmap": "hive"}
],
"locations" : [ "wilderness" ],
"occurrences" : [1, 6],
"rotate" : false,
"spawns" : { "group" : "GROUP_BEE", "population":[20,60], "radius":[2,4] }
},{
"type" : "overmap_special",
"id" : "Cabin",
"overmaps" : [
{ "point":[0,0,0], "overmap": "cabin"}
],
"locations" : [ "wilderness" ],
"occurrences" : [1, 10],
"rotate" : false,
"flags" : [ "CLASSIC" ]
},{
"type" : "overmap_special",
"id" : "Strange Cabin",
"overmaps" : [
{ "point":[0,0,0], "overmap": "cabin_strange"},
{ "point":[0,0,-1], "overmap": "cabin_strange_b"}
],
"locations" : [ "forest" ],
"occurrences" : [1, 1],
"rotate" : false,
"flags" : [ "CLASSIC" ]
},{
"type" : "overmap_special",
"id" : "Strangle Temple",
"overmaps" : [
{ "point":[0,0,0], "overmap": "temple_stairs"},
{ "point":[0,0,-1], "overmap": "temple_stairs"},
{ "point":[0,0,-2], "overmap": "temple_stairs"},
{ "point":[0,0,-3], "overmap": "temple_stairs"},
{ "point":[0,0,-4], "overmap": "temple_stairs"},
{ "point":[0,0,-5], "overmap": "temple_finale"}
],
"locations" : [ "forest", "swamp" ],
"occurrences" : [1, 3],
"rotate" : false
},{
"type" : "overmap_special",
"id" : "Standing stones",
"overmaps" : [
{ "point":[0,0,0], "overmap": "standing_stones"}
],
"locations" : [ "forest"],
"occurrences" : [1, 1],
"rotate" : false
},{
"type" : "overmap_special",
"id" : "Anthill",
"overmaps" : [
{ "point":[0,0,0], "overmap": "anthill"}
],
"locations" : [ "wilderness" ],
"occurrences" : [1, 6],
"rotate" : false,
"spawns" : { "group" : "GROUP_ANT", "population":[1000,2000], "radius":[10,30] }
},{
"type" : "overmap_special",
"id" : "Spider Pit",
"overmaps" : [
{ "point":[0,0,0], "overmap": "spider_pit"},
{ "point":[0,0,-1], "overmap": "spider_pit_under"}
],
"locations" : [ "forest" ],
"occurrences" : [1, 500],
"rotate" : false
},{
"type" : "overmap_special",
"id" : "Slime Pit",
"overmaps" : [
{ "point":[0,0,0], "overmap": "slimepit_down"}
],
"locations" : [ "land", "swamp" ],
"occurrences" : [1, 4],
"rotate" : false,
"spawns" : { "group" : "GROUP_GOO", "population":[100,200], "radius":[2,10] }
},{
"type" : "overmap_special",
"id" : "Fungal Bloom",
"overmaps" : [
{ "point":[0,0,0], "overmap": "fungal_bloom"}
],
"locations" : [ "wilderness" ],
"occurrences" : [1, 3],
"rotate" : false,
"spawns" : { "group" : "GROUP_FUNGI", "population":[600,1200], "radius":[30,50] }
},{
"type" : "overmap_special",
"id" : "Fungal Tower",
"overmaps" : [
{ "point":[0,0,0], "overmap": "fungal_tower"}
],
"locations" : [ "wilderness" ],
"occurrences" : [1, 2],
"rotate" : false,
"spawns" : { "group" : "GROUP_FUNGI_TOWER", "population":[125,175], "radius":[2,2] }
},{
"type" : "overmap_special",
"id" : "Fungal Flowers",
"overmaps" : [
{ "point":[0,0,0], "overmap": "fungal_flowers"}
],
"locations" : [ "wilderness", "swamp" ],
"occurrences" : [1, 2],
"rotate" : false,
"spawns" : { "group" : "GROUP_FUNGI_FLOWERS", "population":[50,100], "radius":[2,4] }
},{
"type" : "overmap_special",
"id" : "Triffid Grove",
"overmaps" : [
{ "point":[0,0,0], "overmap": "triffid_grove"},
{ "point":[0,0,-1], "overmap": "triffid_roots"},
{ "point":[0,0,-2], "overmap": "triffid_finale"}
],
"locations" : [ "forest" ],
"occurrences" : [1, 4],
"rotate" : false,
"spawns" : { "group" : "GROUP_TRIFFID", "population":[800,1300], "radius":[12,20] }
},{
"type" : "overmap_special",
"id" : "Cave",
"overmaps" : [
{ "point":[0,0,0], "overmap": "cave"}
],
"locations" : [ "wilderness", "swamp" ],
"occurrences" : [1, 30],
"rotate" : false
},{
"type" : "overmap_special",
"id" : "bandit_cabin",
"overmaps" : [
{ "point":[0,0,0], "overmap": "bandit_cabin"}
],
"locations" : [ "forest" ],
"occurrences" : [1, 1],
"rotate" : false,
"flags" : [ "CLASSIC" ]
},{
"type" : "overmap_special",
"id" : "bandit_camp",
"overmaps" : [
{ "point":[0,0,0], "overmap": "bandit_camp_1"},
{ "point":[1,0,0], "overmap": "bandit_camp_2"},
{ "point":[0,1,0], "overmap": "bandit_camp_3"},
{ "point":[1,1,0], "overmap": "bandit_camp_4"}
],
"locations" : [ "forest" ],
"occurrences" : [1, 1],
"rotate" : false,
"flags" : [ "CLASSIC" ]
},{
"type" : "overmap_special",
"id" : "Pond",
"overmaps" : [
{ "point":[0,0,0], "overmap": "pond_field"}
],
"locations" : [ "field" ],
"occurrences" : [0, 15],
"rotate" : false,
"flags" : [ "CLASSIC" ]
},{
"type" : "overmap_special",
"id" : "basin",
"overmaps" : [
{ "point":[0,0,0], "overmap": "pond_forest"}
],
"locations" : [ "forest" ],
"occurrences" : [0, 12],
"rotate" : false,
"flags" : [ "CLASSIC" ]
},{
"type" : "overmap_special",
"id" : "bog",
"overmaps" : [
{ "point":[0,0,0], "overmap": "pond_swamp"}
],
"locations" : [ "swamp" ],
"occurrences" : [0, 9],
"rotate" : false,
"flags" : [ "CLASSIC" ]
},{
"type": "overmap_special",
"id": "Swamp Shack",
"overmaps": [
{ "point":[0,0,0], "overmap": "hunter_shack"}
],
"locations": [ "swamp" ],
"occurrences": [1, 4],
"rotate" : false,
"flags": [ "CLASSIC" ]
},{
"type": "overmap_special",
"id": "Hunting Blind",
"overmaps": [
{ "point": [ 0, 0, 0 ], "overmap": "hunting_blind_north" }
],
"locations": [ "wilderness" ],
"occurrences": [ 1, 20 ]
}
]

[ZenZen2]

Confirming this bug.
Keep everything on default, also default mods, only change city size to 0.
started 3 times with the play now scenario, 2 out of 3 i end up in the woods with no specials on the whole overmap. 1 out of the 3 there were specials but the next overmap after teleporting had none.

[ZenZen2]

I think setting city size to 0 breaks city distance somehow, but thats just a theory.

[mlangsdorf]

I tried this.
First overmap: large river running north to south across the overmap, no specials aside from bogs and basins.
Second overmap: smaller river running from north edge to northern side of the eastern edge, plenty of specials: bee hives, toxic waste dumps, etc.
Third overmap: larger river running from almost the north edge to the south edge, no specials, not even bogs or basins.
Fourth overmap: larger river running from almost the north edge to the south edge, no specials, not even bogs or basins.
Fifth overmap: multiple large rivers running from edge to edge, no specials, not even bogs or basins.
Sixth overmap: larger river running from almost the north edge to the south edge, no specials, not even bogs or basins.

Is something in the river generation code breaking the other specials somehow?