Group settlements into realms (city-states / kingdoms / empires) and give them
territory + political borders, all derived deterministically from the saved
settlement set (no save-version bump, step-back free).
- PlanetNation.{hpp,cpp}: computeTerritory() — size-scaled influence range per
settlement, realm grouping (a town joins the nearest larger capital within its
annexation reach, else founds its own nation), tier by member count / total pop,
and per-cell ownership maximising range - angular-distance (wilderness frontiers
where no settlement reaches). No RNG → tectonic stream untouched.
- Territory colour mode + nationColor, buildNationBorders (plate dual-contour
reused), realm labels at capitals, a Realms info tab, cell-info realm line, and
kind=4 WorldEvents (realm founded / rises to empire / collapsed). Key P toggles
the view + borders; territory recomputed once per sim year, on placement, load
and step-back.
- civTerritory*/civVassalRange/civEmpire* config knobs (self-describing → no save
break); test_nation.cpp covers ownership/wilderness, empires vs city-states,
realm grouping, tiers, determinism, RNG isolation, save/load parity.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
