The base cloud/rain field relaxes to a static pattern under fixed forcing, so it looked
frozen. stepWeather now also runs a population of drifting WeatherSystem agents (world
objects, not cells; transient/not saved; separate sWeatherRng seeded from cfg.seed so
tectonic determinism is intact): spawn over warm tropical ocean (5-25 deg, SST gate) or a
mid-latitude ocean low (capped at weatherSystemMax); move along the steering wind (sWind at
the nearest cell) plus a poleward recurve at weatherSystemSpeed; intensify over warm sea,
decay and cull over land/cold; and stamp a Gaussian cloud/rain shield onto the grid so cloud
clusters travel and dissipate behind them. A tropical system past weatherHurricaneStr is a
hurricane/typhoon.
Render: an animated cyclonic spiral marker per system (red + eye for cyclones, blue lows;
spins with liveTime by hemisphere) in 3D + 2D, HUD system/cyclone counts, and a basin-named
storm list in the Sky & tides panel -- all under K. New weather* storm knobs. test_weather.cpp
adds: systems spawn, move between steps, thicken cloud, RNG isolation, determinism. All five
suites pass; GUI build clean. Docs updated.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
A per-cell humidity/cloud/rain cycle advanced on the live clock (PlanetWeather.cpp,
raylib-free): evaporate over warm sunlit seas -> advect humidity & cloud along the prevailing
wind (upwind differencing) -> condense into cloud (saturation vs temperature + windward
orographic lift) -> rain out thick cloud -> dissipate. Bounded exp-rate forms keep it stable at
any timestep, so it runs cleanly from hours/sec up to a month/sec. initWeather() spins the
fields up from the moisture climatology; fully deterministic (no RNG).
Render: a translucent cloud shell over the 3D globe (white -> dark slate where it rains,
alpha = cover) plus a matching drawWeather2D layer on the 2D map (shared drawMapTris
rasterizer), toggled with K (default on). stepSim runs stepWeather each live frame at the
sim-hours added to liveTime (held when paused). Cell-info shows cloud/humidity/raining.
Saved as v10 (humidity/cloud/rain, flag-gated; pre-v10 saves spin weather up live). New
weather* config knobs. Reseed/regen now also drops out of Live World. test_weather.cpp:
fields in range, clouds form + rain falls, oceans moister than land, determinism, v10
round-trip; the other four suites still pass; GUI build clean. Docs updated.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
