Settlers scale with empty homes: fast catch-up, slowing near full

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

README.md

@@ -35,8 +35,8 @@ Alpha. One season, bandit raids plus two friendly events, six buildings.
   Construction also saws planks, which higher building levels need, and
   builds fittings from them: one-off upgrades a building takes once it's high
   enough (shelving, a well pump, weapon racks, enchanted chests…). Population eats food,
-  pays taxes, and fills the houses (empty homes draw settlers, about a
+  pays taxes, and fills the houses (empty homes draw settlers, half of
-  quarter of all homes a day, plus slow family growth); it promotes the settlement
+  them a day, so it slows as the houses fill, plus slow family growth); it promotes the settlement
   (hamlet, village at 40, town at 90, city at 150), which raises building
   level caps and gives everyone bank slots.
 - **Prayer:** enemies drop bones; burying them gives prayer points and

game.py

@@ -482,9 +482,9 @@ TIERS = [
     {"name": "City", "pop": 150, "cap": 99, "houses": 8},
 ]
 TIER_SLOTS = 2
-# Growth: empty homes draw settlers (a share of all the homes, every day, while
+# Growth: empty homes draw settlers, fast while many stand empty and slower as
-# any stand empty), and families grow a little on their own.
+# they fill, and families grow a little on their own however full the city is.
-SETTLERS_PER_HOME = 0.25
+SETTLERS_PER_EMPTY_HOME = 0.5
 FAMILY_GROWTH = 0.05
 
 RAID_GROUPS = ["the Red Hand", "the Hollow Crows", "the Blackwater gang", "the Ashen Wolves",
@@ -1437,7 +1437,7 @@ def _start_next(world: dict, now: float) -> None:
 def growth_per_day(world: dict) -> float:
     """New townsfolk a day while there's room: settlers for the homes, plus families."""
     pop = world["city"]["population"]
-    growth = SETTLERS_PER_HOME * housing(world) + FAMILY_GROWTH * pop
+    growth = SETTLERS_PER_EMPTY_HOME * max(0.0, housing(world) - pop) + FAMILY_GROWTH * pop
     return growth * city_rate(world, "growth") * (1.25 if fitted(world, "furniture") else 1)
 
 

tests/test_game.py

@@ -315,13 +315,14 @@ class CityTest(unittest.TestCase):
         city["population"] = 22.0
         city["buildings"]["houses"]["level"] = 2
         city["stockpile"] = {"bread": 10_000}
-        self.assertAlmostEqual(game.growth_per_day(world), 0.25 * 65 + 0.05 * 22)
+        self.assertAlmostEqual(game.growth_per_day(world), 0.5 * 43 + 0.05 * 22)
         for _hour in range(24):
             game._city_hour(world, T0)
         self.assertGreater(city["population"], 38)
-        for _hour in range(48):
+        # Slower as the homes fill, but never down to nothing.
-            game._city_hour(world, T0)
+        self.assertLess(game.growth_per_day(world), 0.5 * 43)
-        self.assertEqual(city["population"], 65)
+        city["population"] = 64.0
+        self.assertAlmostEqual(game.growth_per_day(world), 0.5 + 3.2)
 
     def test_fed_city_grows_to_housing_and_pays_tax(self):
         world = world_with()