Jonas Reith
ab2c4024f8
Cities used to climb a hugely stacked carrying capacity (K up to 20-40M for the best trade hubs -- civMaxPopulation x habitability x siteQuality x conditions x trade) at ~2%/yr for millennia: bounded in principle, endless in practice. Three fixes, all population-only + derived vectors (pure hashes, no RNG, no save-version bump, step-back exact): - Urban crowding: mortality rises with the square of city size (civCrowdingLoss x (P/civMetropolisPop)^2 per year), so the best hubs PLATEAU at a historical metropolis scale (~1-1.5M) instead of chasing K; negligible below ~50k, not a clamp. - Good-year cap (civCondBoomCap): a lucky harvest no longer inflates the K target by 70% (the logistic chased booms at full rate while famine corrected busts slowly -- an upward ratchet); droughts stay uncapped. - Plagues (civPlague*): rare deterministic epidemics (1-3-year waves, 20-40% deaths at full exposure) strike cities (exposure 0 below ~30k), harder when trade-connected -- contagion travels the routes, the historical check on big hubs. Derived sCivPlague + cell-info PLAGUE line + "Plague ravages X" / "Plague shrinks X" kind-3 events. Retuned: civMaxPopulation 2e6 -> 1e6 (it is a capacity SCALE, not a cap -- comment fixed), civEmpirePop 5e6 -> 2.5e6 for the new sizes. test_civ gains a plateau/plague section: with the new model the largest city settles ~1.1M vs 3.7M-and-climbing without it; villages never plague; waves are deterministic, twin-identical and rewind exactly. All 16 suites pass. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>