airutils/wind.lua

--[[
MIT License

Copyright (c) 2019 TheTermos, TestificateMods

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local get_wind

if minetest.get_modpath("climate_api") then
	get_wind = function(pos, multiplier)
        multiplier = multiplier or 0.1
		local wind = climate_api.environment.get_wind({x=0,y=0,z=0})
		return vector.multiply(wind, multiplier)
	end

else
	local yaw = math.random()*math.pi*2-math.pi
    local speed = math.random()*4.0
	airutils.wind={}
	airutils.wind.wind = vector.multiply(minetest.yaw_to_dir(yaw),speed)
	airutils.wind.timer = 0
	airutils.wind.ttime = math.random()*5*60+1*60

	get_wind = function(pos, multiplier)
        local retVal = vector.multiply(airutils.wind.wind, multiplier)
		return retVal
	end

	minetest.register_globalstep(
	function(dtime)
		airutils.wind.timer=airutils.wind.timer+dtime
		if airutils.wind.timer >= airutils.wind.ttime then
			local yaw = minetest.dir_to_yaw(airutils.wind.wind)
			yaw = yaw+math.random()-0.5
            local speed = math.random()*4.0
			airutils.wind.wind = vector.multiply(minetest.yaw_to_dir(yaw),speed)
			airutils.wind.ttime = airutils.wind.timer+math.random()*5*60+1*60
		end
	end)
end

return get_wind