# Rain filth: no input, the scene idles under the default rain (0.35)
# and smog (starts 0.5; the tuned atmosphere holds it there). Soot
# settles on the deck (grime_deck grows steadily) and the rain washes
# it toward the river (grime_river grows on the wash + its own
# deposition; the outflow only wins over longer horizons).
# frames: 1200
