Biome indices into world.options.biomes, strongest first (length count).
Continentalness, −1 (deep ocean) … 1 (deep inland).
Number of valid entries in biomes/weights.
Height above the base surface (plane y = 0 / planet radius), metres.
Erosion field 0 (rugged) … 1 (flat).
Moisture 0 … 1.
Mountain contribution 0 … 1 (share of full mountain height).
0 … 1 strength of the river channel here.
Temperature at this altitude, °C.
0 … 1 strength of the river valley here.
Water surface height (sea or river), or NaN where dry.
Weights matching biomes, summing to 1.
Everything known about one point of the world. Reuse one object across calls (pass it as
out).