12 lines
500 B
Lua
12 lines
500 B
Lua
function weather_mod.set_headwind(player)
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local movement = vector.normalize(player:get_player_velocity())
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local product = vector.dot(movement, weather_mod.state.wind)
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-- logistic function, scales between 0 and 2
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-- see https://en.wikipedia.org/wiki/Logistic_function
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local L = 1.6 -- maximum value
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local k = 0.15 -- growth rate
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local z = 0.8 -- midpoint
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local o = 0.1 -- y offset
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local factor = L / (1 + math.exp(-k * (product - z))) + o
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weather_mod.add_physics(player, "speed", factor)
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end |