# Fire spread (the FIRE_FIXTURE driver): the brazier is a permanent
# ignition source; the DOWNWIND fixture (wind 0.375 m/s FROM 25 ->
# lattice step (+1,+2), alignment 0.99) accumulates heat and ignites,
# the UPWIND fixture (alignment -0.99) never does under the default
# manual weather (rain 1.4 mm/h suppresses but does not kill).
# frames: 2800
